ChemPlusChem最新文献

Diketopiperazine (DKP), a recurring product of silica-catalyzed amino acid polymerization, is a molecule of interest in the origin of life studies, as well in the industrial medicinal chemistry. Its role in the peptide bond formation reactions is controversial as it is considered sometimes as a stable, dead-end product for the oligomerization reaction. We tried to elucidate the parameters that govern the DKP opening on silica surfaces of low and high surface areas in the frame of glycine polymerization reaction, when DKP is adsorbed from gas and liquid phases, or subjected to temperature and humidity fluctuations cycles. The formed products were characterized by infrared spectroscopy, thermogravimetric analysis, and X-ray diffraction. The results reveal that DKP represents an efficient intermediate for the polymerization reaction leading to the formation of linear peptides on silica surfaces. Abundant oligomers with β-sheet secondary structures are formed depending on the DKP loading and the silica surface. The crucial role of the silica surface including the “nearly free” silanols in the adsorption, opening, and reaction of DKP to form linear chains was shown. These conclusions highlight the complexity of the DKP surface chemistry in the polymerization reaction and can improve the understanding when dealing with geochemical prebiotic scenarios.

The rapid intensification of anthropogenic nitrogen cycle perturbations and the energy-intensive nature of Haber–Bosch process have motivated the pursuit of sustainable routes for ammonia synthesis. Electrocatalytic nitrogen reduction reaction (NRR) represents a compelling strategy to convert inert N₂ into NH₃, yet its practical realization remains constrained by formidable activation barriers, sluggish kinetics, and strong competition from hydrogen evolution reaction. Well-defined metal clusters have emerged as a distinctive catalytic platform, offering tunable electronic structures and active motifs that bridge the gap between single-atom catalysts and nanoparticles. Our review establishes a unified framework for understanding cluster-enabled NRR, beginning with the physicochemical principles of N₂ activation, including orbital interactions, reaction energetics, and key activity descriptors, while considering electrolyte and proton-coupled effects. We then analyze cluster characteristics such as size-dependent electronic behavior, geometric configurations, and support interactions, highlighting their implications for catalytic selectivity. A systematic overview of electrocatalytic platforms is presented, including metal clusters, bimetallic systems, heterostructures, and nitrogenase-inspired architectures, followed by critical perspectives on reproducibility, durability, and future development pathways. Looking ahead, the integration of operando characterization, theoretical modeling, and scalable synthesis is expected to accelerate the rational development of efficient and reliable cluster-based NRR systems.

Covalent triazine frameworks (CTFs) have promising photocatalytic applications including water treatment and the conversion of CO₂. This study investigates the utilization of the commercially available precursors 1,2-dicyanobenzene (1,2-DCB) and 1,3-dicyanobenzene (1,3-DCB) to synthesise novel CTF-type materials. The structure and properties of these materials are compared with those of the benchmark photocatalyst CTF-1, which is synthesised from 1,4-dicyanobenzene (1,4-DCB). Although the materials derived from 1,2-DCB and 1,3-DCB as well as 1,4-DCB contain triazine units characteristic of CTFs, the 2D and 3D structural properties differ substantially depending on the DCB precursor. The geometry of 1,2-DCB prevents the formation of ordered porous networks, leading to materials that lack semiconducting properties, hence without potential use in photocatalysis. By contrast, materials derived from 1,3-DCB show greater similarity to CTF-1, with a proposed extended 2D network structure, a high thermal stability, and visible light absorption. However, the crystallinity and overall surface area of the 1,3-DCB-derived products are lower than values reported for CTF-1. Photocatalytic activity towards the aerobic oxidation of benzylamine is demonstrated for the catalysts derived from 1,3-DCB and compared with materials prepared from 1,4-DCB. Overall, this study demonstrates that commercially available DCBs can form triazine-containing CTF-type materials with tuneable structural and optical properties.

Driven by the urgent global water remediation demands, piezocatalysis, as an emerging green tech, has quickly become a massive research hotspot. Piezocatalysis breaks free from the high energy costs and strict operating conditions that often hold back traditional catalysts by directly converting mechanical energy into usable chemical energy. This review systematically tracks the design progress of piezocatalytic materials. This work provides an in-depth analysis of the dynamic mechanisms revealing how mechanical stress induces endogenous polarization fields to precisely regulate charge separation and reactive oxygen species (ROS) generation. We heavily focus on what is happening at the nanoscale-morphology tweaks, interface engineering, and polarization enhancement by tracing the evolutionary path of these materials. This article shed light on how active sites dynamically adapt under stress by pairing density functional theory calculations with in situ characterization. Finally, we map out the road ahead, tackling the macrolevel engineering challenges of mitigating nanomaterial fatigue, improving anticorrosion performance in complex waters, and designing viable continuous-flow reactors.

Interlocked peptide molecules exhibit peptidase resistance as well as enzyme inhibitory activity, making them promising candidates for peptide-based drugs. Lasso peptides possess a [1]rotaxane structure, in which a peptide chain threads through the cavity of the cyclic peptide moiety. However, the construction of such peptide-based interlocked structures remains highly challenging, and the total chemical synthesis of natural lasso peptides has not yet been achieved. Here, we aim to develop a synthetic method for a peptide-based rotaxane using a metal-template strategy. A macrocyclic complex bearing a Pd(II) ion fixed by a pincer ligand is employed to examine the threading of Val-8mer in DMSO. Pseudorotaxane formation is assessed by characteristic ¹H NMR shifts and DOSY measurements, and is confirmed by electrospray ionization mass spectrometry (ESI-MS). Titration and variable-temperature (VT) NMR experiments are also performed to elucidate the dynamic behavior of the rotaxanation. These results demonstrate the feasibility of creating lasso-peptide-like architectures via metal-templated rotaxanation, providing a new strategy for the synthesis of natural and artificial lasso peptides.

It is of significance that abundant biomass sucrose is converted into the high-value-added formic acid (FA) through the sucrose oxidative reaction (SOR). Herein, the high melting point metal rhenium (Re) is doped into the Sb₂O₃ to form Re-Sb₂O₃ nanoblock. The Re-Sb₂O₃ has narrower bandgap and more active sites, so it shows good electrocatalytic performances with a low SOR potential of 1.28 V at 10 mA cm⁻² and a hydrogen evolution reaction (HER) overpotential of 173 mV at 10 mA cm⁻² in 1 M KOH + 0.1 M sucrose, which are superior to Sb₂O₃ and commercial RuO₂ and Pt/C. The Re-Sb₂O₃ successfully catalyzes sucrose to FA according to the ¹H NMR data with a high Faradaic efficiency (FE) of 87.7% at 1.6 V. This work provides a strategy for biomass sucrose upcycling to protect environment linking to hydrogen evolution.

In this work, we have synthesised and spectroscopically characterised an acyl hydrazone-based chemosensor, H₂L, through two intermediate steps. Remarkably, this chemosensor exhibits selective recognition of Zn(II) and Al(III) ions in 9:1 EtOH–water and DMSO–water media, respectively, among competing cations. Followed by an optical colour change, the presence of Zn(II) and Al(III) ions enhances the luminescence property of the probe H₂L. The limit of detection for both ions is within the nanomolar range. As a practical advantage, the sensor can also be employed in several applications for easy, on-site detection, such as paper strips, cotton buds, and fluorescent ink. The chelation-enhanced fluorescence emission in the presence of two target cations is the primary reason for the increased emission intensity when both analytes are present. The probe-analyte NMR titration confirms the deprotonation of H2L and its coordination to the target metal ions. The Job's plot and mass spectral data are used to assess the stoichiometric addition of the probe to the analyte. The high binding constants obtained for the probe–analyte interactions confirm strong affinity between H₂L and the target ion, which is further supported by the successful isolation and characterisation of the corresponding solid Zn(II) complex (complex 1).

A new ferrocene (Donor) phenyl (π) conjugated phthalimide and naphthalimide (Acceptors) chromophores, Fc-Ph-PI (1) and Fc-Ph-NI (2), were synthesized and characterized. Single-crystal X-ray diffraction studies revealed that chromophore 2 crystallizes centrosymmetric monoclinic P2₁/n space group with non-covalent interactions (intermolecular hydrogen bonding and CH…π interactions), which favors SHG efficiencies. The solvatochromic studies were conducted to elucidate the intramolecular charge–transfer (ICT) process, which results in a 46 nm blueshift in the emission spectra of chromophore 2 relative to its absorption spectra, due to a higher ground-state dipole moment. The aggregation-induced emission (AIE) studies in THF/H₂O mixture at 90% showed enhanced emission for chromophore 2 due to restricted intramolecular rotation (RIR). Additionally, chromophore 2 exhibited mechanofluorochromic and acidochromic behavior, which resulted in an increased emission maximum and intensity. The second-order non-linear optical (NLO) property of the chromophores was studied using Kurtz Perry powder technique, utilizing KDP as a standard reference. Chromophore 2 exhibits 1.35 times higher Second Harmonic Generation (SHG) efficiency than chromophore 1, attributed to efficient charge transfer facilitated by enhanced π-extension of the naphthalimide acceptor. Furthermore, density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations were performed to validate the experimental results using B3LYP/6-31+G** level of theory.

Hydrogen peroxide (H₂O₂) is an environmentally beneficial intermediate essential to human biological metabolism. However, the human body may suffer serious cellular damage because of the overproduction and buildup of excess H₂O₂. For the detection of H₂O₂, the Ag₂S/NiS-adhered reduced graphene oxide (Ag₂S/NiS/rGO) nanozyme was developed, which oxidizes 3, 3, 5, 5-tetramethylbenzidine (TMB) into a blue-colored product, resulting in the development of an efficient and cost-effective colorimetric method. In real sample analysis, this approach showed good recovery (97.5%–100.6%) and a sensitivity to H₂O₂ concentrations from 0.1 to 100 mM, with the lowest limit of H₂O₂ observed at 0.1 mM, with K_m value as low as 0.498 mM. Additionally, investigations on selectivity, storage stability (3 weeks), and recycling stability were conducted. The same nanozyme is also utilized to remove organic dyes when H₂O₂ is present. According to the results, methyl orange (MO) and rhodamine B (RhB) dyes decay in 8 and 6 min, respectively, with apparent rate constants of 0.02287/min for MO and 0.02132/min for RhB. This multifunctional nanozyme offers a promising platform for real-time environmental monitoring and sustainable wastewater treatment by enabling sensitive H₂O₂ detection and rapid degradation of hazardous organic dyes.

Chiral nematic mesoporous organosilica materials, inspired by the coassembly of cellulose nanocrystals (CNCs) and organosilica precursors, offer unprecedented opportunities for designing functional nanostructures with tunable physicochemical properties. Templating approaches leveraging the intrinsic chirality and nematic ordering of CNCs enable the fabrication of highly ordered organosilica with controlled natural morphology. These chiral nematic materials have properties that make them suitable for applications in optics, decoration, catalysis, and adsorption. Recent advances demonstrate that precise modulation of their structural and surface characteristics can unlock new functionalities, positioning CNC-templated chiral organosilica films as a powerful platform for next-generation “fine and smart” materials science.