Journal of Materials Chemistry C最新文献

Volatile threshold memristive switches are attractive for the fabrication of artificial compact neurons, third-order neuromorphic elements, and reservoir computing (RC) systems. The latter have emerged as a powerful neuromorphic framework for efficient temporal signal processing, offering a compelling combination of computational efficiency and low training cost. A key challenge, however, lies in finding hardware platforms that possess the necessary short-term memory and nonlinear dynamics to serve as physical reservoirs. In this work, we address this by introducing a volatile bi-layer nanocomposite-based (Co–Fe–B)–LiNbO_x/(NbO_y)–LiNbO_z memristor, which exhibits pronounced and batch-to-batch reproducible short-term memory properties. A distinctive feature of this device is the cooperative nature of its threshold and resistive switching, allowing it to be modeled as a parallel connection of an NbO₂-based selector and a LiNbO₃-based nonvolatile memristor. We demonstrate that even a compact hardware system built around a single memristor can perform complex tasks. Specifically, we achieved 97.1% accuracy in handwritten-digit recognition from the MNIST dataset and a low normalized root mean square error of 0.028 in predicting the chaotic Hénon map time-series. This study expands the range of promising volatile nanocomposite memristive structures for neuromorphic computing applications, while additionally paving the way toward scalable, high-performance memristor-based RC systems for efficient complex temporal and spatial information processing.

With the growing demand for clean energy and the limitations of traditional photovoltaic technologies, perovskite solar cells (PSCs) have emerged as a promising next-generation photovoltaic option due to their high efficiency and low-cost fabrication. However, inorganic electron transport layers (ETLs) face challenges such as high-temperature processing requirements and poor interface compatibility, restricting the further development of PSCs. This review systematically summarizes the research progress of five types of organic ETLs (fullerenes and their derivatives, aromatic imide derivatives, polycyclic aromatic hydrocarbons, polymer-based materials, and organic–inorganic hybrids) in PSCs, focusing on molecular structure design, optoelectronic properties, and device performance regulation. The analysis of structure–performance relationships and existing challenges (e.g., high cost, insufficient stability, and poor large-area film formation) provides insights for optimizing organic ETLs, which is of great significance for promoting the commercialization of high-efficiency, stable, and low-cost PSCs.

Correction for ‘Efficient transparent blue-emitted perovskite light-emitting diodes based on multilayer transparent top electrodes’ by Zhenghao He et al., J. Mater. Chem. C, 2024, 12, 7162–7168, https://doi.org/10.1039/D4TC00934G.

The photo-switchable trans–cis isomerization of azobenzene endows it with excellent photofunctional characteristics, including high quantum yield, minimal photobleaching and distinct conformational changes, making it a classic building block for fabricating advanced photo-responsive functional materials. The integration of azobenzene and molecular containers through reversible host–guest interactions has emerged as a powerful strategy for constructing photo-responsive systems, in which trans-azobenzene stably embeds into the cavity of molecular containers, while light-induced trans-to-cis isomerization triggers complex dissociation due to the bent conformation and enhanced hydrophilicity of cis-azobenzene, thus realizing precise light-mediated regulation of material properties. In this review, we systematically summarize the latest progress of photo-responsive polymeric materials based on azobenzene–molecular container host–guest interactions over the past three years, with an exclusive focus on covalent polymeric materials and covalent molecular containers. The reviewed content is innovatively categorized according to the polymerization components, namely “polymerization of azobenzene”, “polymerization of molecular container”, and “polymerization of both azobenzene and molecular container”, which clarifies the diverse design paradigms of such photofunctional materials. We detail the structural design, photo-responsive mechanisms and functional applications of the representative materials, and further discuss the key challenges and future development directions of this research field. This review is expected to provide a comprehensive summary of the current research status and offers novel perspectives for the rational design and fabrication of next-generation photofunctional polymeric materials based on azobenzene–molecular container host–guest interactions.

Electrocaloric (EC) cooling is a promising alternative to conventional vapor-compression refrigeration by virtue of its potential for miniaturization, its high energy efficiency, cost-effectiveness, and environmental benignity. However, the practical application of lead-free EC ceramic materials is hindered by the challenge of simultaneously realizing a large adiabatic temperature change (ΔT) and a broad operating temperature span (T_span). In this work, Sm³⁺ was doped into the A-sites of a Ba_0.9Sr_0.1Ti_0.93Sn_0.07O₃ ceramic system to modify its ferroelectric polarization and relaxor behavior. The (Ba_0.9Sr_0.1)_0.995Sm_0.005Ti_0.93Sn_0.07O₃ ceramic exhibits a ΔT of 3.8 K at an electric field of 200 kV cm⁻¹ near room temperature, accompanied by a wide T_span of 78 °C. A decrease in oxygen-vacancy concentration with increasing Sm³⁺ doping content significantly improves the dielectric breakdown strength of the ceramics. The enhanced breakdown strength effectively boosts spontaneous polarization, thus enabling excellent room-temperature electrocaloric performance. This work provides a facile and effective compositional regulation strategy for optimizing the electrocaloric properties of BaTiO₃-based ceramics for solid-state cooling applications.

Magnetic continuum robots (MCRs) hold significant promise for minimally invasive procedures due to their simple design and ease of miniaturization. However, the current deformation capabilities of MCRs are constrained by fixed magnetization configurations, leading to potential collisions with surrounding environments and limited access to hard-to-reach areas. In this study, we introduce a reprogrammable magnetic continuum robot (RMCR) driven by a proximal programmable unit (PPU). The RMCR can be selectively reprogrammed in real time using the melting and solidification of a low-melting-point alloy (LMPA). We conducted an in-depth investigation of the kinematic properties of the RMCR and the thermal characteristics of the PPU through modeling, numerical simulations, and experimental validation. The results show that the measured deflection angle of the RMCR and the complete phase transition temperature of the LMPA align closely with the simulation predictions. Additionally, by strategically embedding shape memory alloy clips on the distal drive unit of the RMCR, we successfully demonstrated obstacle capture and targeted drug delivery within a vascular model.

Clustering of dopant cations commonly occurs when they are incorporated into host matrices, particularly at high doping levels. In this work, we demonstrated, even at low doping levels, the energetically favorable formation of isovalently substituted Ti⁴⁺ clusters in the monoclinic phase of ZrO₂ (m-ZrO₂) using photoluminescence spectroscopy, extended X-ray absorption fine structure (EXAFS) spectroscopy and first-principles density functional theory (DFT) calculations. The oxygen vacancy–Ti dopant interactions critically reduce the doping energy cost, and Ti doping is favored for oxygen deficiency formation. The Ti⁴⁺ clusters feature a high degree of excited-state electron delocalization following charge-transfer (CT) excitation (O²⁻ → Ti⁴⁺) and are responsible for the reduced quenching concentration and doping-dependent excitation band redshift. The occurrence of Ti⁴⁺ clustering was analyzed using a model that involved the electronegativity of dopant/host cations and the inherent neutral oxygen vacancies. The formation mechanism established is anticipated to be extendable to a broader range of material systems.

Lanthanide-doped nanoparticles (LnNPs) exhibit attractive luminescence in the second near-infrared range due to their bright, narrow-linewidth, non-blinking and non-bleaching emission. Hindered by the insulating matrices of these nanoparticles, it has been challenging to realize electroluminescent devices based on LnNPs under low operating voltages. Recently, Yu et al. achieved a breakthrough by constructing LnNP@organic molecule nanohybrids and utilizing efficient triplet energy transfer to LnNPs, enabling narrowband NIR-II electroluminescence under low turn-on voltages of approximately 5 V (Z. Yu, Y. Deng, J. Ye, et al., Nature, 2025, 647, 625–631). These results open a new direction for optoelectronic devices based on lanthanides and offer promising opportunities for flexible electronics, near-infrared communication, and quantum light sources.

Nonlinear optical (NLO) materials underpin frequency conversion, ultrafast modulation, and light–matter control, yet conventional bulk crystals face practical constraints in tunability and integration. Motivated by the rapid expansion of low-dimensional, interface-engineered, and topology-driven platforms, this review provides a unified perspective on second- and third-order nonlinear responses across material dimensionalities, spanning bulk and bulk-like crystals to two-dimensional (2D) layers, van der Waals heterostructures, and quantum dots. We connect the fundamental framework of nonlinear susceptibilities with key structure–property design rules – particularly symmetry breaking, electronic asymmetry, confinement, and interface effects – and summarize experimental routes used to quantify χ⁽²⁾ and χ⁽³⁾. A central theme is the emergence of topology-enabled nonlinear optics, where Berry-phase geometry (including Berry curvature and the quantum metric) reshapes NLO design from symmetry–resonance optimization towards symmetry–geometry co-design, enabling robust nonlinear photocurrents and harmonic responses. We further review machine-learning strategies that accelerate screening and inverse design by extracting hidden descriptors and enabling rapid property prediction across large chemical spaces. Finally, we outline near-term opportunities and bottlenecks for translating material demonstrations into manufacturable, on-chip nonlinear photonic systems for frequency translation, ultrafast signal processing, and quantum photonics.

Hydrogen is recognized as a clean energy carrier whose safe and efficient utilization relies on accurate and reliable sensing technologies. Among various sensing mechanisms, resistive hydrogen sensors based on metal oxide semiconductors (MOS) have drawn considerable interest owing to their high sensitivity, fast response, low cost, and compatibility with integration. This review systematically outlines recent advances in MOS-based hydrogen sensors, focusing on representative materials such as SnO₂, ZnO, WO₃, and TiO₂. Starting from the intrinsic properties of these materials, including crystal structure, electronic band features, and defect chemistry, the underlying gas-sensing mechanisms are thoroughly analyzed. To enhance sensitivity, selectivity, response speed, and stability, four major material design strategies are examined in detail: nanostructure engineering, noble-metal functionalization, heterojunction construction, and defect control. These approaches act synergistically to tailor surface redox kinetics, catalytic activity, and interfacial charge transport, thereby enabling performance-oriented optimization of the sensors. Unlike a simple summary of reported materials and sensing performances, this review links intrinsic material properties, hydrogen-sensing mechanisms, and performance-enhancement strategies within a materials-oriented framework. By adopting a materials-centric and mechanism-oriented perspective, it aims to provide useful guidance for the rational design of high-performance MOS hydrogen sensors and to stimulate further progress in next-generation hydrogen detection technologies.