Nano-Structures & Nano-Objects最新文献_第3页

Synthesized graphene-silicon oxides hybrid nanocomposite using laser ablation for optoelectronic and antibacterial activity 利用激光烧蚀法合成石墨烯-氧化硅杂化纳米复合材料

IF 5.45 Q1 Physics and Astronomy

Nano-Structures & Nano-Objects

Pub Date : 2026-05-01 Epub Date: 2026-05-27 DOI: 10.1016/j.nanoso.2026.101695

Khansaa Haleem Mohsin , Ehssan Al-Bermany , Siti Azrah Mohamad Samsuri , Ahmed M. Amshawee , Naser M. Ahmed

Green methods for synthesizing nanocomposites revealed unique properties, making them versatile for multi-biophysical applications. Pulsed laser ablation (PLAL), using a pulsed Q-Switched CO₂ laser to synthesize graphene oxide-silicon dioxide (GO@SiO₂) with an energy of 250 mJ and 10.6 μm wavelength. Three different times (1, 2.5, and 5) minutes were applied for each pulse. Fourier-transform infrared spectroscopy revealed a strong bond between the GO and SiO₂ nanomaterials. Field-emission scanning electron microscopy and energy-dispersive X-ray Spectroscopy confirmed that increasing the pulse time increased the element content. The Raman spectra confirm the successful formation of GO@SiO₂ nanocomposites, preserving the graphitic structure (D and G bands) alongside the characteristic Si–O–Si vibrational modes. Increasing PLAL ablation time enhances peak intensity and improves interfacial interaction between GO and silica. Dynamic light scattering revealed the size of the nanoparticles and demonstrated the presence of a monolayer and a few GO layers in the SiO₂ nanoparticle system. Based on its optical properties, GO@SiO₂ exhibits an absorption peak between 200 and 280 nm. The energy bandgap decreased from 4.7 eV to 4.28 eV and from 4.2 eV to 3.8 eV for the allowed and forbidden transitions, respectively. It was observed that as the concentration of synthesized GO nanosheets was increased, the inhibition zones of E. coli and S. aureus increased from 06 mm to 20 mm and from 21 mm, respectively. GO@SiO₂ nanoparticles exhibit a significant cytotoxic effect against HT-29 colon cancer cells. The syntheses of GO demonstrated promising properties for optoelectronic devices and biological applications.

绿色合成纳米复合材料的方法显示出独特的性能，使其具有多种生物物理应用。脉冲激光烧蚀（PLAL），利用脉冲调q CO2激光器合成能量为250 mJ、波长为10.6 μm的氧化石墨烯-二氧化硅（GO@SiO2）。每次脉冲施加三种不同的时间（1、2.5和5）分钟。傅里叶变换红外光谱显示氧化石墨烯和二氧化硅纳米材料之间有很强的结合。场发射扫描电子显微镜和能量色散x射线光谱学证实，增加脉冲时间增加元素含量。拉曼光谱证实了GO@SiO₂纳米复合材料的成功形成，保留了石墨结构（D和G波段）以及特征的Si-O-Si振动模式。增加PLAL烧蚀时间可以增强峰值强度，改善氧化石墨烯与二氧化硅之间的界面相互作用。动态光散射揭示了纳米颗粒的大小，并证明了SiO2纳米颗粒体系中存在单层和少量氧化石墨烯层。根据其光学性质，GO@SiO2的吸收峰在200 ~ 280 nm之间。允许跃迁和禁止跃迁的能带隙分别从4.7 eV减小到4.28 eV和4.2 eV减小到3.8 eV。结果表明，随着合成氧化石墨烯纳米片浓度的增加，对大肠杆菌和金黄色葡萄球菌的抑制区分别从06 mm增加到20 mm和21 mm。GO@SiO纳米粒子对HT-29结肠癌细胞具有显著的细胞毒性作用。氧化石墨烯的合成在光电器件和生物应用方面表现出了良好的性能。

{"title":"Synthesized graphene-silicon oxides hybrid nanocomposite using laser ablation for optoelectronic and antibacterial activity","authors":"Khansaa Haleem Mohsin , Ehssan Al-Bermany , Siti Azrah Mohamad Samsuri , Ahmed M. Amshawee , Naser M. Ahmed","doi":"10.1016/j.nanoso.2026.101695","DOIUrl":"10.1016/j.nanoso.2026.101695","url":null,"abstract":"<div><div>Green methods for synthesizing nanocomposites revealed unique properties, making them versatile for multi-biophysical applications. Pulsed laser ablation (PLAL), using a pulsed Q-Switched CO<sub>2</sub> laser to synthesize graphene oxide-silicon dioxide (GO@SiO<sub>2</sub>) with an energy of 250 mJ and 10.6 μm wavelength. Three different times (1, 2.5, and 5) minutes were applied for each pulse. Fourier-transform infrared spectroscopy revealed a strong bond between the GO and SiO<sub>2</sub> nanomaterials. Field-emission scanning electron microscopy and energy-dispersive X-ray Spectroscopy confirmed that increasing the pulse time increased the element content. The Raman spectra confirm the successful formation of GO@SiO₂ nanocomposites, preserving the graphitic structure (D and G bands) alongside the characteristic Si–O–Si vibrational modes. Increasing PLAL ablation time enhances peak intensity and improves interfacial interaction between GO and silica. Dynamic light scattering revealed the size of the nanoparticles and demonstrated the presence of a monolayer and a few GO layers in the SiO<sub>2</sub> nanoparticle system. Based on its optical properties, GO@SiO<sub>2</sub> exhibits an absorption peak between 200 and 280 nm. The energy bandgap decreased from 4.7 eV to 4.28 eV and from 4.2 eV to 3.8 eV for the allowed and forbidden transitions, respectively. It was observed that as the concentration of synthesized GO nanosheets was increased, the inhibition zones of <em>E. coli and S. aureus</em> increased from 06 mm to 20 mm and from 21 mm, respectively. GO@SiO₂ nanoparticles exhibit a significant cytotoxic effect against HT-29 colon cancer cells. The syntheses of GO demonstrated promising properties for optoelectronic devices and biological applications.</div></div>","PeriodicalId":397,"journal":{"name":"Nano-Structures & Nano-Objects","volume":"46 ","pages":"Article 101695"},"PeriodicalIF":5.45,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148184108","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Biomass-derived activated carbon supported silver nanoparticles for water disinfection: A comprehensive review 生物质源活性炭负载纳米银用于水消毒：综述

IF 5.45 Q1 Physics and Astronomy

Nano-Structures & Nano-Objects

Pub Date : 2026-05-01 Epub Date: 2026-05-15 DOI: 10.1016/j.nanoso.2026.101689

Belete Tessema, Getahun Tefera, Glen Bright

This comprehensive review explores biomass-derived activated carbon supported silver nanoparticles (AgNPs) as a sustainable solution for water disinfection. Water contamination from pathogens, organic pollutants, and heavy metals poses significant health risks globally, emphasizing the need for effective, affordable treatment technologies. AgNPs exhibit potent antimicrobial properties, especially at the nanoscale, but face challenges such as stability, environmental toxicity, and leaching. Supporting AgNPs on biomass-derived activated carbon—obtained from agricultural waste, forestry residues, and other biomass sources—enhances stability, dispersibility, and reusability while aligning with green chemistry principles. The synthesis methods, including chemical reduction and green approaches, produce uniform, well-dispersed nanoparticles anchored onto porous carbon supports, resulting in efficient microbial inactivation through mechanisms like silver ion release, reactive oxygen species generation, and membrane disruption. The porous structure facilitates pollutant adsorption, concentrating microbes near active silver sites. Laboratory studies demonstrate rapid bactericidal and virucidal effects, high reusability, and minimal silver leaching. However, challenges such as scaling synthesis, long-term stability, and environmental safety remain. Future directions involve optimizing immobilization techniques, developing eco-friendly synthesis routes, and integrating these nanocomposites into multifunctional water treatment systems. Biomass-supported AgNPs hold promise for sustainable, cost-effective, and efficient water sanitation, especially in resource-limited settings, contributing to global health and environmental sustainability.

这篇综合综述探讨了生物质衍生活性炭负载纳米银（AgNPs）作为水消毒的可持续解决方案。来自病原体、有机污染物和重金属的水污染在全球范围内构成重大健康风险，强调需要有效、负担得起的处理技术。AgNPs表现出强大的抗菌性能，特别是在纳米尺度上，但面临稳定性、环境毒性和浸出等挑战。在从农业废弃物、林业废弃物和其他生物质来源获得的生物质衍生活性炭上支持AgNPs，可以增强稳定性、分散性和可重复使用性，同时符合绿色化学原则。包括化学还原和绿色方法在内的合成方法，生产出均匀、分散良好的纳米颗粒，锚定在多孔碳载体上，通过银离子释放、活性氧生成和膜破坏等机制，有效地使微生物失活。多孔结构有利于污染物吸附，将微生物集中在活性银位点附近。实验室研究表明，快速杀菌和杀病毒的效果，高可重复使用，和最小的银浸出。然而，诸如结垢合成、长期稳定性和环境安全性等挑战仍然存在。未来的发展方向包括优化固定技术，开发生态友好的合成路线，以及将这些纳米复合材料集成到多功能水处理系统中。生物质支持的AgNPs有望实现可持续、具有成本效益和高效的水卫生，特别是在资源有限的情况下，有助于全球健康和环境的可持续性。

{"title":"Biomass-derived activated carbon supported silver nanoparticles for water disinfection: A comprehensive review","authors":"Belete Tessema, Getahun Tefera, Glen Bright","doi":"10.1016/j.nanoso.2026.101689","DOIUrl":"10.1016/j.nanoso.2026.101689","url":null,"abstract":"<div><div>This comprehensive review explores biomass-derived activated carbon supported silver nanoparticles (AgNPs) as a sustainable solution for water disinfection. Water contamination from pathogens, organic pollutants, and heavy metals poses significant health risks globally, emphasizing the need for effective, affordable treatment technologies. AgNPs exhibit potent antimicrobial properties, especially at the nanoscale, but face challenges such as stability, environmental toxicity, and leaching. Supporting AgNPs on biomass-derived activated carbon—obtained from agricultural waste, forestry residues, and other biomass sources—enhances stability, dispersibility, and reusability while aligning with green chemistry principles. The synthesis methods, including chemical reduction and green approaches, produce uniform, well-dispersed nanoparticles anchored onto porous carbon supports, resulting in efficient microbial inactivation through mechanisms like silver ion release, reactive oxygen species generation, and membrane disruption. The porous structure facilitates pollutant adsorption, concentrating microbes near active silver sites. Laboratory studies demonstrate rapid bactericidal and virucidal effects, high reusability, and minimal silver leaching. However, challenges such as scaling synthesis, long-term stability, and environmental safety remain. Future directions involve optimizing immobilization techniques, developing eco-friendly synthesis routes, and integrating these nanocomposites into multifunctional water treatment systems. Biomass-supported AgNPs hold promise for sustainable, cost-effective, and efficient water sanitation, especially in resource-limited settings, contributing to global health and environmental sustainability.</div></div>","PeriodicalId":397,"journal":{"name":"Nano-Structures & Nano-Objects","volume":"46 ","pages":"Article 101689"},"PeriodicalIF":5.45,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147951159","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Co-precipitated engineered nanocrystalline magnesium oxide: Structural symmetry and thermal behavior analysis insights 共沉淀工程纳米晶氧化镁：结构对称性和热行为分析见解

IF 5.45 Q1 Physics and Astronomy

Nano-Structures & Nano-Objects

Pub Date : 2026-05-01 Epub Date: 2026-05-30 DOI: 10.1016/j.nanoso.2026.101702

Fariha Zannat , Mohshin Maola , Md. Ashraful Alam , Debasish Sarkar , Raton Kumar Bishwas , Subarna Sandhani Dey , Shirin Akter Jahan

Highly crystalline magnesium oxide nanoparticles (MgO NPs) with a pronounced preferential orientation along the (2 0 0) plane were synthesized by a simple co-precipitation route. The X-ray diffraction and Rietveld refinement confirmed the formation of phase-pure cubic MgO (99.20 %) with a lattice parameter of 4.2158 Å and an average crystallite size of 29.35 nm. The NPs exhibited a wide optical band gap of 5.90 eV and a high specific surface area of 60.96 m² g⁻¹ . Thermal analysis demonstrated good stability, with an activation energy of 32.25 kJ mol⁻¹ and an exothermic crystallization event at 511.3–520.5 °C (ΔH= 5.843 J g⁻¹), indicating the transformation of residual amorphous domains into crystalline MgO. Transmission electron microscopy (TEM) revealed predominantly spheroidal particles with a mean size of 33.95 nm, while HR-TEM showed an interplanar spacing of 0.2103 nm, corresponding to the dominant (2 0 0) plane without a defect. The synthesized MgO NPs showed broad-spectrum antimicrobial activity against Gram-positive and Gram-negative bacteria and fungal strains. These results demonstrate that the combination of nanoscale dimensions, high phase purity MgO NPs with multifunctional properties, makes them promising candidates for antimicrobial ceramic coatings technologies.

采用简单共沉淀法合成了沿（2 ~ 0）平面具有明显择优取向的高结晶氧化镁纳米颗粒（MgO NPs）。x射线衍射和Rietveld细化证实形成了相纯立方MgO(99.20%)，晶格参数为4.2158 Å，平均晶粒尺寸为29.35 nm。NPs具有5.90 eV的宽带隙和60.96 m²g⁻¹ 的高比表面积。热分析表明其稳定性良好，活化能为32.25 kJ mol⁻¹ ，在511.3-520.5°C （ΔH= 5.843 J g⁻¹）时发生放热结晶事件，表明残留的无定形结构域转变为结晶MgO。透射电子显微镜（TEM）显示，颗粒主要为球形，平均尺寸为33.95 nm，而HR-TEM显示的面间距为0.2103 nm，对应于优势（2 0 0）面，无缺陷。合成的MgO NPs对革兰氏阳性和革兰氏阴性细菌和真菌具有广谱抗菌活性。这些结果表明，纳米级尺寸，高相纯度的MgO NPs具有多功能特性，使其成为抗菌陶瓷涂层技术的有希望的候选者。

{"title":"Co-precipitated engineered nanocrystalline magnesium oxide: Structural symmetry and thermal behavior analysis insights","authors":"Fariha Zannat , Mohshin Maola , Md. Ashraful Alam , Debasish Sarkar , Raton Kumar Bishwas , Subarna Sandhani Dey , Shirin Akter Jahan","doi":"10.1016/j.nanoso.2026.101702","DOIUrl":"10.1016/j.nanoso.2026.101702","url":null,"abstract":"<div><div>Highly crystalline magnesium oxide nanoparticles (MgO NPs) with a pronounced preferential orientation along the (2 0 0) plane were synthesized by a simple co-precipitation route. The X-ray diffraction and Rietveld refinement confirmed the formation of phase-pure cubic MgO (99.20 %) with a lattice parameter of 4.2158 Å and an average crystallite size of 29.35 nm. The NPs exhibited a wide optical band gap of 5.90 eV and a high specific surface area of 60.96 m² g⁻¹ . Thermal analysis demonstrated good stability, with an activation energy of 32.25 kJ mol⁻¹ and an exothermic crystallization event at 511.3–520.5 °C (ΔH= 5.843 J g⁻¹), indicating the transformation of residual amorphous domains into crystalline MgO. Transmission electron microscopy (TEM) revealed predominantly spheroidal particles with a mean size of 33.95 nm, while HR-TEM showed an interplanar spacing of 0.2103 nm, corresponding to the dominant (2 0 0) plane without a defect. The synthesized MgO NPs showed broad-spectrum antimicrobial activity against Gram-positive and Gram-negative bacteria and fungal strains. These results demonstrate that the combination of nanoscale dimensions, high phase purity MgO NPs with multifunctional properties, makes them promising candidates for antimicrobial ceramic coatings technologies.</div></div>","PeriodicalId":397,"journal":{"name":"Nano-Structures & Nano-Objects","volume":"46 ","pages":"Article 101702"},"PeriodicalIF":5.45,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148184110","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Response surface optimization of fluoride sequestration using L-lysine stabilized mesoporous silica xerogel l -赖氨酸稳定介孔二氧化硅凝胶固氟响应面优化

IF 5.45 Q1 Physics and Astronomy

Nano-Structures & Nano-Objects

Pub Date : 2026-05-01 Epub Date: 2026-05-13 DOI: 10.1016/j.nanoso.2026.101685

Atul Srivastava , Anushree Srivastava

This study evaluates the fluoride removal efficiency of L-lysine functionalized silica xerogel and optimizes the adsorption process using response surface methodology. SEM and EDX studies revealed an irregular porous morphology with elemental composition, while XRD confirmed the predominantly amorphous silica framework. FTIR indicated characteristic Si–O–Si and –NH functional groups. BET analysis showed a high specific surface area of 245.16 m² g⁻¹ , and XPS confirmed siloxane (Si–O–Si) linkages (Si 2p at 103.4 eV) along with nitrogen-containing functionalities. Batch adsorption experiments assessed the effects of pH, initial fluoride concentration, adsorbent dosage, contact time, and temperature. The equilibrium data followed the Langmuir isotherm, indicating monolayer adsorption, while kinetics were best described by the pseudo-second-order model, suggesting chemisorption. Thermodynamic parameters confirmed that the adsorption process was spontaneous and endothermic. A central composite design generated a statistically significant quadratic model (p < 0.0001), identifying pH and initial fluoride concentration as the most influential factors. Under optimized conditions of pH 6.6, fluoride concentration 14.4 mg/L, adsorbent dosage 3.0 g/L, contact time 164 min, and temperature 31.35 °C, a maximum removal efficiency of 99.52% was predicted and experimentally validated. These results demonstrate the potential applicability of the functionalized silica xerogel for effective fluoride removal from contaminated water.

本研究评价了l -赖氨酸功能化二氧化硅凝胶的除氟效果，并利用响应面法对吸附工艺进行了优化。SEM和EDX研究显示元素组成不规则的多孔形态，而XRD证实主要是无定形的二氧化硅骨架。FTIR显示特征Si-O-Si和-NH官能团。BET分析显示其高比表面积为245.16 m²g⁻¹ ，XPS证实了硅氧烷（Si - o - Si）键（Si 2p在103.4 eV）以及含氮功能。批量吸附实验评估了pH、初始氟浓度、吸附剂用量、接触时间和温度的影响。平衡数据符合Langmuir等温线，表明其为单层吸附，而动力学模型则符合拟二阶模型，表明其为化学吸附。热力学参数证实了吸附过程是自发的吸热过程。中心复合设计产生了统计上显著的二次模型（p <； 0.0001），确定pH和初始氟化物浓度是影响最大的因素。在pH 6.6、氟浓度14.4 mg/L、吸附剂投加量3.0 g/L、接触时间164 min、温度31.35℃的条件下，预测最大去除率为99.52%。这些结果证明了功能化二氧化硅干凝胶在有效去除污染水中氟化物方面的潜在适用性。

{"title":"Response surface optimization of fluoride sequestration using L-lysine stabilized mesoporous silica xerogel","authors":"Atul Srivastava , Anushree Srivastava","doi":"10.1016/j.nanoso.2026.101685","DOIUrl":"10.1016/j.nanoso.2026.101685","url":null,"abstract":"<div><div>This study evaluates the fluoride removal efficiency of <span>L</span>-lysine functionalized silica xerogel and optimizes the adsorption process using response surface methodology. SEM and EDX studies revealed an irregular porous morphology with elemental composition, while XRD confirmed the predominantly amorphous silica framework. FTIR indicated characteristic Si–O–Si and –NH functional groups. BET analysis showed a high specific surface area of 245.16 m² g⁻¹ , and XPS confirmed siloxane (Si–O–Si) linkages (Si 2p at 103.4 eV) along with nitrogen-containing functionalities. Batch adsorption experiments assessed the effects of pH, initial fluoride concentration, adsorbent dosage, contact time, and temperature. The equilibrium data followed the Langmuir isotherm, indicating monolayer adsorption, while kinetics were best described by the pseudo-second-order model, suggesting chemisorption. Thermodynamic parameters confirmed that the adsorption process was spontaneous and endothermic. A central composite design generated a statistically significant quadratic model (p < 0.0001), identifying pH and initial fluoride concentration as the most influential factors. Under optimized conditions of pH 6.6, fluoride concentration 14.4 mg/L, adsorbent dosage 3.0 g/L, contact time 164 min, and temperature 31.35 °C, a maximum removal efficiency of 99.52% was predicted and experimentally validated. These results demonstrate the potential applicability of the functionalized silica xerogel for effective fluoride removal from contaminated water.</div></div>","PeriodicalId":397,"journal":{"name":"Nano-Structures & Nano-Objects","volume":"46 ","pages":"Article 101685"},"PeriodicalIF":5.45,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147951160","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Facile co-precipitation synthesis of bismuth ferrite (Bi₂Fe₄O₉) nanoparticles: Structural, morphological, optical, and photocatalytic characterization 铋铁氧体（Bi₂Fe₄O₉）纳米粒子的易溶共沉淀法合成：结构、形态、光学和光催化表征

IF 5.45 Q1 Physics and Astronomy

Nano-Structures & Nano-Objects

Pub Date : 2026-05-01 Epub Date: 2026-04-30 DOI: 10.1016/j.nanoso.2026.101666

Ahmed M. Ajam, Khalid Haneen Abass

The wide range of Bismuth compounds offers various applications, whereas bismuth ferrite is one of the suitable compounds for photocatalytic applications. In this paper, a successful preparation of bismuth ferrite (Bi₂Fe₄O₉) by a simple and low-cost co-precipitation method is presented, aiming to develop a photocatalyst for the treatment of organic pollutants. The structural, morphological, and optical properties of the sample were analyzed using XRD, SEM, and FTIR techniques. XRD results showed the formation of a pure crystalline phase with a highly regular mullite structure and nanocrystals with an average size of 30 nm, while SEM images revealed interconnected quasi-spherical particles that enhance charge transport. Spectral analyses confirmed the presence of characteristic peaks of Fe–O and Bi–O bonds within the structure, in addition to active surface –OH groups that contribute to the generation of hydroxyl radicals. The optical absorption spectrum showed an energy gap of 2.3 eV, suggesting potential responsiveness to both ultraviolet and visible regions. In photocatalytic tests, the catalyst achieved approximately 12% degradation of methylene blue dye within 150 min under UV irradiation, with an apparent pseudo-first-order rate constant of 4.0 × 10⁻⁴ min⁻¹ and a regression coefficient of R² = 0.9267, outperforming direct photodegradation. Comparative analysis with literature reports indicates that higher efficiencies (up to 80–99%) and faster kinetics have been achieved in optimized Bi₂Fe₄O₉ systems, where rate constants typically fall within the range of 10⁻³ to 10⁻² min⁻¹ . The reaction followed apparent first-order kinetics, indicating a surface-controlled mechanism. The results indicate that Bi₂Fe₄O₉ possesses suitable structural and electronic properties for photocatalytic applications; however, its activity under the present conditions remains limited, highlighting the need for further optimization. This could be achieved through strategies such as heterostructure formation or controlled doping to enhance charge separation and extend light absorption toward the visible region

铋化合物种类繁多，具有多种用途，而铋铁氧体是光催化应用的合适化合物之一。本文介绍了一种简单、低成本的共沉淀法成功制备了铋铁氧体（Bi₂Fe₄O₉），旨在开发一种用于处理有机污染物的光催化剂。采用XRD、SEM和FTIR技术对样品的结构、形貌和光学性质进行了分析。XRD结果表明，制备出了具有高度规则莫来石结构的纯晶相和平均尺寸为30 nm的纳米晶体，SEM图像显示了相互连接的准球形颗粒，增强了电荷输运。光谱分析证实了结构内存在Fe-O和Bi-O键的特征峰，以及有助于羟基自由基生成的活性表面-OH基团。光吸收光谱显示出2.3 eV的能隙，表明对紫外和可见光区都有潜在的响应性。在光催化测试中，该催化剂在紫外线照射下在150 min内对亚甲基蓝染料实现了约12%的降解，其表观伪一阶速率常数为4.0 × 10⁻⁴min⁻¹ ，回归系数为R²= 0.9267，优于直接光降解。与文献报告的比较分析表明，优化的Bi₂Fe₄O₉体系具有更高的效率（高达80-99%）和更快的动力学，其速率常数通常在10⁻³ 到10⁻²min⁻¹ 之间。反应明显遵循一级动力学，表明表面控制机理。结果表明，Bi₂Fe₄O₉具有适合光催化应用的结构和电子性能；然而，它在目前条件下的活动仍然有限，突出表明需要进一步优化。这可以通过异质结构形成或控制掺杂等策略来实现，以增强电荷分离并将光吸收扩展到可见光区域

{"title":"Facile co-precipitation synthesis of bismuth ferrite (Bi₂Fe₄O₉) nanoparticles: Structural, morphological, optical, and photocatalytic characterization","authors":"Ahmed M. Ajam, Khalid Haneen Abass","doi":"10.1016/j.nanoso.2026.101666","DOIUrl":"10.1016/j.nanoso.2026.101666","url":null,"abstract":"<div><div>The wide range of Bismuth compounds offers various applications, whereas bismuth ferrite is one of the suitable compounds for photocatalytic applications. In this paper, a successful preparation of bismuth ferrite (Bi₂Fe₄O₉) by a simple and low-cost co-precipitation method is presented, aiming to develop a photocatalyst for the treatment of organic pollutants. The structural, morphological, and optical properties of the sample were analyzed using XRD, SEM, and FTIR techniques. XRD results showed the formation of a pure crystalline phase with a highly regular mullite structure and nanocrystals with an average size of 30 nm, while SEM images revealed interconnected quasi-spherical particles that enhance charge transport. Spectral analyses confirmed the presence of characteristic peaks of Fe–O and Bi–O bonds within the structure, in addition to active surface –OH groups that contribute to the generation of hydroxyl radicals. The optical absorption spectrum showed an energy gap of 2.3 eV, suggesting potential responsiveness to both ultraviolet and visible regions. In photocatalytic tests, the catalyst achieved approximately 12% degradation of methylene blue dye within 150 min under UV irradiation, with an apparent pseudo-first-order rate constant of 4.0 × 10⁻⁴ min⁻¹ and a regression coefficient of R² = 0.9267, outperforming direct photodegradation. Comparative analysis with literature reports indicates that higher efficiencies (up to 80–99%) and faster kinetics have been achieved in optimized Bi₂Fe₄O₉ systems, where rate constants typically fall within the range of 10⁻³ to 10⁻² min⁻¹ . The reaction followed apparent first-order kinetics, indicating a surface-controlled mechanism. The results indicate that Bi₂Fe₄O₉ possesses suitable structural and electronic properties for photocatalytic applications; however, its activity under the present conditions remains limited, highlighting the need for further optimization. This could be achieved through strategies such as heterostructure formation or controlled doping to enhance charge separation and extend light absorption toward the visible region</div></div>","PeriodicalId":397,"journal":{"name":"Nano-Structures & Nano-Objects","volume":"46 ","pages":"Article 101666"},"PeriodicalIF":5.45,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147798012","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Functional impacts of carbon-based nanomaterials in the performance of heterostructure photocatalysts for the remediation of pharmaceutical pollutants in wastewater- A review 碳基纳米材料对异结构光催化剂修复废水中药物污染物性能的影响研究进展

IF 5.45 Q1 Physics and Astronomy

Nano-Structures & Nano-Objects

Pub Date : 2026-05-01 Epub Date: 2026-05-05 DOI: 10.1016/j.nanoso.2026.101675

Joshua A. Oyetade , Opeyemi A. Iresemowo , Mariam I. Adeoba , Omolola E. Fayemi , Sunday F. Abimbade , Adeyemi O. Adeeyo

The toxicity, persistence, and recalcitrance of pharmaceutically active compounds (PhACs) in wastewater to conventional treatment methods are attributable to their chemical stability, low biodegradability, and structural complexity. However, studies have identified photocatalytic treatment in advanced oxidation processes (AOPs) as a panacea for these targeted pollutants. The review evaluates the unique dimensions of carbon-based nanomaterials (CBNMs) coupled with metals, metal oxides and metal-organic frameworks to form heterostructure photocatalysts. It assessed their functional role in the hybrid photocatalysts. The findings revealed that CBNMs act as electron sinks to capture photogenerated excitons (e^--h⁺). This is due to their π−conjugation and lower bandgap properties, which significantly improve the redox processes during photocatalytic degradation of pollutants in wastewater. Also, the study revealed that various structural dimensions of CBNMs coupled with semiconductors act as electron mediators, inducing accelerated charge transfer and a unique shift of absorption edge to higher wavelength for rapid visible photon absorption. The study specifically presents 2D reduced graphene oxide and 1D carbon nanotubes (CNTs) with bandgap narrowing potentials, structural stability and superior electron delocalization among other CBNMs applied in heterostructure development. Also, the use of a heteroatom doping strategy refines the electronic structure of CBNMs, which creates the premise for prolonged photoinduced carrier lifetime. In addition, a desired charge carrier mechanism of Z-Scheme and the recent S-scheme was accomplished with the formed heterostructure, with photodegradation performance of over 95%. This presents a suitable pathway for advanced treatment techniques for the recalcitrant pharmaceutical pollutants in wastewater.

废水中药物活性化合物（PhACs）的毒性、持久性和顽固性是由于其化学稳定性、低生物降解性和结构复杂性。然而，研究已经确定了在高级氧化过程（AOPs）中的光催化处理是解决这些目标污染物的灵丹妙药。综述了碳基纳米材料（CBNMs）与金属、金属氧化物和金属有机骨架耦合形成异质结构光催化剂的独特尺寸。评价了它们在杂化光催化剂中的功能作用。研究结果表明，CBNMs作为电子汇捕获光生激子（e—h+）。这是由于它们的π−共轭和较低的带隙性质，这显著改善了光催化降解废水中污染物的氧化还原过程。此外，研究还发现，不同的结构尺寸与半导体耦合的CBNMs作为电子介质，诱导加速电荷转移和独特的吸收边缘向更高波长的移动，以快速吸收可见光子。该研究特别介绍了2D还原氧化石墨烯和1D碳纳米管（CNTs）在异质结构开发中的应用，它们具有带隙缩小电位、结构稳定性和优异的电子离域性。此外，杂原子掺杂策略的使用改进了cbnm的电子结构，这为延长光诱导载流子寿命创造了前提。此外，形成的异质结构完成了Z-Scheme和最近的S-scheme所期望的载流子机制，光降解性能超过95%。这为废水中顽固性药物污染物的深度处理技术提供了一条合适的途径。

{"title":"Functional impacts of carbon-based nanomaterials in the performance of heterostructure photocatalysts for the remediation of pharmaceutical pollutants in wastewater- A review","authors":"Joshua A. Oyetade , Opeyemi A. Iresemowo , Mariam I. Adeoba , Omolola E. Fayemi , Sunday F. Abimbade , Adeyemi O. Adeeyo","doi":"10.1016/j.nanoso.2026.101675","DOIUrl":"10.1016/j.nanoso.2026.101675","url":null,"abstract":"<div><div>The toxicity, persistence, and recalcitrance of pharmaceutically active compounds (PhACs) in wastewater to conventional treatment methods are attributable to their chemical stability, low biodegradability, and structural complexity. However, studies have identified photocatalytic treatment in advanced oxidation processes (AOPs) as a panacea for these targeted pollutants. The review evaluates the unique dimensions of carbon-based nanomaterials (CBNMs) coupled with metals, metal oxides and metal-organic frameworks to form heterostructure photocatalysts. It assessed their functional role in the hybrid photocatalysts. The findings revealed that CBNMs act as electron sinks to capture photogenerated excitons (e<sup>-</sup>-h<sup>+</sup>). This is due to their π−conjugation and lower bandgap properties, which significantly improve the redox processes during photocatalytic degradation of pollutants in wastewater. Also, the study revealed that various structural dimensions of CBNMs coupled with semiconductors act as electron mediators, inducing accelerated charge transfer and a unique shift of absorption edge to higher wavelength for rapid visible photon absorption. The study specifically presents 2D reduced graphene oxide and 1D carbon nanotubes (CNTs) with bandgap narrowing potentials, structural stability and superior electron delocalization among other CBNMs applied in heterostructure development. Also, the use of a heteroatom doping strategy refines the electronic structure of CBNMs, which creates the premise for prolonged photoinduced carrier lifetime. In addition, a desired charge carrier mechanism of Z-Scheme and the recent S-scheme was accomplished with the formed heterostructure, with photodegradation performance of over 95%. This presents a suitable pathway for advanced treatment techniques for the recalcitrant pharmaceutical pollutants in wastewater.</div></div>","PeriodicalId":397,"journal":{"name":"Nano-Structures & Nano-Objects","volume":"46 ","pages":"Article 101675"},"PeriodicalIF":5.45,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147849700","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Innovative technologies for solar energy conversion: A review of emerging materials and their efficiency trends 太阳能转换的创新技术：新兴材料及其效率趋势综述

IF 5.45 Q1 Physics and Astronomy

Nano-Structures & Nano-Objects

Pub Date : 2026-05-01 Epub Date: 2026-05-05 DOI: 10.1016/j.nanoso.2026.101663

Fawad Ahmad , Esha Malik , Syeda Sadaf Batool , Shajia Rehman , Nishat Fatima , Muhammad Imran Khan , Suchandra Bhattacharjee , Mudassar Maraj

Research into new solar energy conversion technologies has increased due to the growing requirement for environmentally friendly and sustainable energy sources. The past few years have seen new photovoltaic materials which include perovskite solar cells (efficiency 26–27%), tandem solar cells (>33%), multi-junction solar cells, organic photovoltaics (19%), dye-sensitized solar cells (14%), quantum dot solar cells (18%), and innovative solar windows which have achieved substantial advances in their ability to transform solar energy into electricity. Next-generation solar cell technologies offer multiple benefits through their flexible design, which enables easy transportation because they can be used in building-integrated solar panels and handheld electronic devices. The review presents a comprehensive assessment of current developments in new solar power technologies, which investigate efficiency improvements and stability issues, and environmental impacts, together with their potential for commercial viability… In addition, lifecycle assessment, circular economy strategies, and machine learning approaches for material optimization are also discussed. Finally, key challenges, future research directions, and a potential roadmap for large-scale development of emerging photovoltaic technologies are highlighted.

由于对环境友好和可持续能源的需求日益增长，对新的太阳能转换技术的研究有所增加。过去几年出现了新的光伏材料，包括钙钛矿太阳能电池（效率26-27%）、串联太阳能电池（>33%）、多结太阳能电池、有机光伏电池（19%）、染料敏化太阳能电池（14%）、量子点太阳能电池（18%）和创新太阳能窗，这些材料在将太阳能转化为电能的能力方面取得了实质性进展。下一代太阳能电池技术通过其灵活的设计提供了多种好处，这使得运输方便，因为它们可以用于建筑集成太阳能电池板和手持电子设备。该综述全面评估了太阳能新技术的最新发展，研究了效率改进和稳定性问题，环境影响，以及它们的商业可行性潜力……此外，还讨论了生命周期评估，循环经济战略和材料优化的机器学习方法。最后，强调了新兴光伏技术大规模发展的关键挑战、未来研究方向和潜在路线图。

{"title":"Innovative technologies for solar energy conversion: A review of emerging materials and their efficiency trends","authors":"Fawad Ahmad , Esha Malik , Syeda Sadaf Batool , Shajia Rehman , Nishat Fatima , Muhammad Imran Khan , Suchandra Bhattacharjee , Mudassar Maraj","doi":"10.1016/j.nanoso.2026.101663","DOIUrl":"10.1016/j.nanoso.2026.101663","url":null,"abstract":"<div><div>Research into new solar energy conversion technologies has increased due to the growing requirement for environmentally friendly and sustainable energy sources. The past few years have seen new photovoltaic materials which include perovskite solar cells (efficiency 26–27%), tandem solar cells (>33%), multi-junction solar cells, organic photovoltaics (19%), dye-sensitized solar cells (14%), quantum dot solar cells (18%), and innovative solar windows which have achieved substantial advances in their ability to transform solar energy into electricity. Next-generation solar cell technologies offer multiple benefits through their flexible design, which enables easy transportation because they can be used in building-integrated solar panels and handheld electronic devices. The review presents a comprehensive assessment of current developments in new solar power technologies, which investigate efficiency improvements and stability issues, and environmental impacts, together with their potential for commercial viability… In addition, lifecycle assessment, circular economy strategies, and machine learning approaches for material optimization are also discussed. Finally, key challenges, future research directions, and a potential roadmap for large-scale development of emerging photovoltaic technologies are highlighted.</div></div>","PeriodicalId":397,"journal":{"name":"Nano-Structures & Nano-Objects","volume":"46 ","pages":"Article 101663"},"PeriodicalIF":5.45,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147849705","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Ultrafast microwave synthesis of highly luminescent carbon quantum dots: Photoluminescence properties and fluorescence sensing of tetracycline 高发光碳量子点的超快微波合成：四环素的光致发光特性和荧光传感

IF 5.45 Q1 Physics and Astronomy

Nano-Structures & Nano-Objects

Pub Date : 2026-05-01 Epub Date: 2026-05-05 DOI: 10.1016/j.nanoso.2026.101667

Rojin Shahriari, Hossein Amani, Arsalan Gholipour

In this research, carbon quantum dots (CDs) with a quantum yield (QY) of 31% were obtained by citric acid and urea via a one-step microwave irradiation process without the need for any supplementary agents. The as-synthesized samples were nano-sized (≈ 4 nm) and had excellent solubility in water, various functional groups, great resilience to environmental factors, and superb optical characteristics. Moreover, various properties of as-prepared CDs, such as morphology, chemical compositions, and graphitic nature, were explained by different analyses, including High transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), and X-ray Diffraction (XRD), respectively. In addition, the as-prepared CDs emitted strong blue fluorescence (FL) at 425 nm when excited by ultraviolet light irradiation (UV) at 360 nm. The findings demonstrated that as-synthesized CDs may be utilized as a sensitive and specific FL indicator for the optical identification of Tetracycline (TC) across a broad spectrum of concentrations ranging from 0 to 400 µM. Impressively, the limit of detection (LOD) was determined to be 1.5 µM based on the quenching of the native FL of CDs. Also, the newly synthesized CDs would serve as a great optical indicator for the identification of TC in various real systems.

在本研究中，以柠檬酸和尿素为原料，通过一步微波辐照工艺制备出量子产率为31%的碳量子点（CDs），无需添加任何辅助剂。合成的样品具有纳米尺寸（≈4 nm），在水中具有良好的溶解度，多种官能团，对环境因素具有良好的弹性，以及优异的光学特性。利用高透射电子显微镜（HRTEM）、x射线光电子能谱（XPS）和x射线衍射仪（XRD）对CDs的形貌、化学成分和石墨性质进行了分析。此外，在所制备的CDs在360 nm紫外光激发下，在425 nm处发出强烈的蓝色荧光（FL）。研究结果表明，合成的CDs可以作为一种敏感和特异性的荧光指示剂，用于在0 ~ 400 µM的广谱范围内光学识别四环素（TC）。令人印象深刻的是，基于CDs的原生FL的猝灭，检测限（LOD）被确定为1.5 µM。同时，新合成的CDs可作为识别各种实际体系中TC的良好光学指标。

{"title":"Ultrafast microwave synthesis of highly luminescent carbon quantum dots: Photoluminescence properties and fluorescence sensing of tetracycline","authors":"Rojin Shahriari, Hossein Amani, Arsalan Gholipour","doi":"10.1016/j.nanoso.2026.101667","DOIUrl":"10.1016/j.nanoso.2026.101667","url":null,"abstract":"<div><div>In this research, carbon quantum dots (CDs) with a quantum yield (QY) of 31% were obtained by citric acid and urea via a one-step microwave irradiation process without the need for any supplementary agents. The as-synthesized samples were nano-sized (≈ 4 nm) and had excellent solubility in water, various functional groups, great resilience to environmental factors, and superb optical characteristics. Moreover, various properties of as-prepared CDs, such as morphology, chemical compositions, and graphitic nature, were explained by different analyses, including High transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), and X-ray Diffraction (XRD), respectively. In addition, the as-prepared CDs emitted strong blue fluorescence (FL) at 425 nm when excited by ultraviolet light irradiation (UV) at 360 nm. The findings demonstrated that as-synthesized CDs may be utilized as a sensitive and specific FL indicator for the optical identification of Tetracycline (TC) across a broad spectrum of concentrations ranging from 0 to 400 µM. Impressively, the limit of detection (LOD) was determined to be 1.5 µM based on the quenching of the native FL of CDs. Also, the newly synthesized CDs would serve as a great optical indicator for the identification of TC in various real systems.</div></div>","PeriodicalId":397,"journal":{"name":"Nano-Structures & Nano-Objects","volume":"46 ","pages":"Article 101667"},"PeriodicalIF":5.45,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147849706","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Influence of aggregate radii, fractal index and extreme packing fraction of the clustered nanoparticle in nanofluid flow: Taguchi and Hermite wavelet-based collocation approach 纳米流体中聚集半径、分形指数和极端堆积分数的影响：基于田口和Hermite小波的配置方法

IF 5.45 Q1 Physics and Astronomy

Nano-Structures & Nano-Objects

Pub Date : 2026-05-01 Epub Date: 2026-05-08 DOI: 10.1016/j.nanoso.2026.101680

K. Karthik , Vishwanatha R. Banakar , P. Siva Kota Reddy , R.J. Punith Gowda

Nanofluids have received considerable attention to enhance heat transfer in rotating and stretching flow systems, and existing literature has investigated the impact of several factors on flow and thermal characteristics. However, most of the current research assumes evenly dispersed nanoparticles and neglects realistic aggregation effects, despite empirical evidence showing that aggregation significantly affects thermophysical properties. Additionally, the role of aggregation properties in nanofluid flow over a revolving cylinder with torsional motion has not been thoroughly examined. Motivated by this research gap, the present investigation examines nanofluid flow with nanoparticle aggregation over a stretching-rotating cylinder subjected to torsional motion in the presence of chemical reactions and thermal radiation. Additionally, the research incorporates aggregation-dependent thermophysical models into the governing equations and compares aggregated and non-aggregated nanofluid behaviour in a unified framework. The resulting nonlinear equations are transformed into ordinary differential equations (ODEs) and solved using the Hermite Wavelet-based collocation method (HWBCM), and the result is validated against the Runge-Kutta-Fehlberg fourth-fifth order (RKF-45) method. A Taguchi optimization analysis is then applied to identify the key parameters impacting heat transfer performance. The results reveal that nanoparticle aggregation enhances heat transfer by modifying velocity, temperature, and concentration boundary layers. Elevating the Reynolds number diminishes the velocity and temperature fields, while thermal radiation enhances the temperature distribution, and higher chemical reactions reduce nanoparticle concentrations. These findings offer helpful insight into developing efficient thermal systems with rotational cylindrical components, such as heat exchangers, rotating cooling devices, and chemical processing machinery.

纳米流体在增强旋转和拉伸流动系统中的传热方面受到了相当大的关注，现有文献研究了几种因素对流动和热特性的影响。然而，目前大多数研究假设纳米颗粒均匀分散，忽略了实际的聚集效应，尽管经验证据表明聚集显著影响热物理性质。此外，聚集性质在纳米流体在具有扭转运动的旋转圆柱体上流动中的作用尚未得到彻底的研究。基于这一研究缺口，本研究考察了在化学反应和热辐射的作用下，纳米颗粒聚集在拉伸旋转圆柱体上进行扭转运动的纳米流体流动。此外，该研究将依赖于聚集的热物理模型纳入控制方程，并在统一的框架内比较聚集和非聚集的纳米流体行为。将得到的非线性方程转化为常微分方程（ODEs），采用基于Hermite小波的配点法（HWBCM）进行求解，并与龙格-库塔-费贝格四五阶（RKF-45）方法进行验证。然后应用田口优化分析确定影响传热性能的关键参数。结果表明，纳米颗粒聚集通过改变速度、温度和浓度边界层来增强传热。雷诺数的增加减小了速度场和温度场，而热辐射增强了温度分布，较高的化学反应降低了纳米颗粒浓度。这些发现为开发具有旋转圆柱形组件的高效热系统提供了有益的见解，例如热交换器，旋转冷却装置和化学加工机械。

{"title":"Influence of aggregate radii, fractal index and extreme packing fraction of the clustered nanoparticle in nanofluid flow: Taguchi and Hermite wavelet-based collocation approach","authors":"K. Karthik , Vishwanatha R. Banakar , P. Siva Kota Reddy , R.J. Punith Gowda","doi":"10.1016/j.nanoso.2026.101680","DOIUrl":"10.1016/j.nanoso.2026.101680","url":null,"abstract":"<div><div>Nanofluids have received considerable attention to enhance heat transfer in rotating and stretching flow systems, and existing literature has investigated the impact of several factors on flow and thermal characteristics. However, most of the current research assumes evenly dispersed nanoparticles and neglects realistic aggregation effects, despite empirical evidence showing that aggregation significantly affects thermophysical properties. Additionally, the role of aggregation properties in nanofluid flow over a revolving cylinder with torsional motion has not been thoroughly examined. Motivated by this research gap, the present investigation examines nanofluid flow with nanoparticle aggregation over a stretching-rotating cylinder subjected to torsional motion in the presence of chemical reactions and thermal radiation. Additionally, the research incorporates aggregation-dependent thermophysical models into the governing equations and compares aggregated and non-aggregated nanofluid behaviour in a unified framework. The resulting nonlinear equations are transformed into ordinary differential equations (ODEs) and solved using the Hermite Wavelet-based collocation method (HWBCM), and the result is validated against the Runge-Kutta-Fehlberg fourth-fifth order (RKF-45) method. A Taguchi optimization analysis is then applied to identify the key parameters impacting heat transfer performance. The results reveal that nanoparticle aggregation enhances heat transfer by modifying velocity, temperature, and concentration boundary layers. Elevating the Reynolds number diminishes the velocity and temperature fields, while thermal radiation enhances the temperature distribution, and higher chemical reactions reduce nanoparticle concentrations. These findings offer helpful insight into developing efficient thermal systems with rotational cylindrical components, such as heat exchangers, rotating cooling devices, and chemical processing machinery.</div></div>","PeriodicalId":397,"journal":{"name":"Nano-Structures & Nano-Objects","volume":"46 ","pages":"Article 101680"},"PeriodicalIF":5.45,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147850281","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

UV-excited pink emissive carbon dots for fluorescent detection of ascorbic acid with additional anti-counterfeiting applications 紫外激发粉红发射碳点荧光检测抗坏血酸与附加防伪应用

IF 5.45 Q1 Physics and Astronomy

Nano-Structures & Nano-Objects

Pub Date : 2026-05-01 Epub Date: 2026-06-03 DOI: 10.1016/j.nanoso.2026.101710

Reshmi Madhukumar Nair , Moisés Armides Franco Molina , Dariush Ebrahimibagha , Nayeli Pineda Aguilar , Jesús Alberto Gómez Treviño , Soorya Pushpan , J.A. Hernández-Magallane , Gloria Lourdes Dimas Rivera , K.C. Sanal

Metal-free carbon dots that exhibit a unique pink fluorescence under UV-excitation were synthesized from biomass source through a green one-pot hydrothermal method using ethanol-oleic acid medium for the first time. The resulting carbon dots were spherical in shape with an average particle size of 2.7 ± 0.43 nm and exhibited excitation dependent fluorescence with a quantum yield of 7.5%. The spectroscopic analysis revealed the existence of two emission bands, a dominant emission band around near UV/blue region and a secondary emission band around red/NIR region. The coexistence of these emissive states produces a combined spectral output perceived as a pink fluorescence under UV illumination, which is a unique optical behaviour for biomass-derived carbon dots. Notably, this NIR emission is achieved without any post-synthetic modification or metal atom doping and indicates the intrinsic surface states generated during carbonization of the precursor. By utilizing these optical properties, the Cdots were used as a fluorescent sensor for the detection of vitamin C with limit of detection (LOD) of 6.2 µM and successfully validated the practical applicability using lemon juice. Furthermore, these unique UV-responsive pink fluorescence enabled the formulation of an invisible ink capable of generating concealed patterns for optical encryption applications such as anticounterfeiting.

首次以生物质为原料，以乙醇-油酸为介质，采用绿色一锅水热法合成了在紫外激发下具有独特粉红色荧光的无金属碳点。所得碳点呈球形，平均粒径为2.7 ± 0.43 nm，具有激发依赖荧光，量子产率为7.5%。光谱分析表明，在紫外/蓝区附近有一个主发射带，在红/近红外区附近有一个次发射带。这些发射状态的共存产生了一个组合的光谱输出，在紫外线照射下被认为是粉红色的荧光，这是生物质衍生碳点的独特光学行为。值得注意的是，这种近红外发射是在没有任何合成后修饰或金属原子掺杂的情况下实现的，并且表明了前驱体碳化过程中产生的本征表面状态。利用这些光学特性，将Cdots作为荧光传感器用于维生素C的检测，检出限（LOD）为6.2 µM，并成功验证了其在柠檬汁中的实用性。此外，这些独特的紫外线响应粉色荧光使隐形墨水的配方能够产生隐藏图案，用于光学加密应用，如防伪。

{"title":"UV-excited pink emissive carbon dots for fluorescent detection of ascorbic acid with additional anti-counterfeiting applications","authors":"Reshmi Madhukumar Nair , Moisés Armides Franco Molina , Dariush Ebrahimibagha , Nayeli Pineda Aguilar , Jesús Alberto Gómez Treviño , Soorya Pushpan , J.A. Hernández-Magallane , Gloria Lourdes Dimas Rivera , K.C. Sanal","doi":"10.1016/j.nanoso.2026.101710","DOIUrl":"10.1016/j.nanoso.2026.101710","url":null,"abstract":"<div><div>Metal-free carbon dots that exhibit a unique pink fluorescence under UV-excitation were synthesized from biomass source through a green one-pot hydrothermal method using ethanol-oleic acid medium for the first time. The resulting carbon dots were spherical in shape with an average particle size of 2.7 ± 0.43 nm and exhibited excitation dependent fluorescence with a quantum yield of 7.5%. The spectroscopic analysis revealed the existence of two emission bands, a dominant emission band around near UV/blue region and a secondary emission band around red/NIR region. The coexistence of these emissive states produces a combined spectral output perceived as a pink fluorescence under UV illumination, which is a unique optical behaviour for biomass-derived carbon dots. Notably, this NIR emission is achieved without any post-synthetic modification or metal atom doping and indicates the intrinsic surface states generated during carbonization of the precursor. By utilizing these optical properties, the Cdots were used as a fluorescent sensor for the detection of vitamin C with limit of detection (LOD) of 6.2 µM and successfully validated the practical applicability using lemon juice. Furthermore, these unique UV-responsive pink fluorescence enabled the formulation of an invisible ink capable of generating concealed patterns for optical encryption applications such as anticounterfeiting.</div></div>","PeriodicalId":397,"journal":{"name":"Nano-Structures & Nano-Objects","volume":"46 ","pages":"Article 101710"},"PeriodicalIF":5.45,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148183985","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0