Materials Science and Engineering: R: Reports最新文献

Hydrogen has emerged as a clean and renewable energy source with the potential to mitigate global energy and environmental crises. Electrolytic water splitting, a highly efficient and sustainable technology, has garnered significant attention for hydrogen production. However, the slow kinetics of the oxygen evolution reaction on the anode and the high energy consumption limit the practicality of industrial-scale electrocatalytic water splitting. To address the challenge, the development of advanced electrolytic systems and the exploration of alternative oxidation reactions are crucial. This review highlights the recent advancements in coupled electrocatalytic hydrogen production strategies, including urea and hydrazine oxidation, value-adding electrosynthesis using small molecules, and waste upcycling and degradation. Various catalysts, the pertinent catalytic mechanisms for anodic oxidation reactions, and methods to decrease the energy barriers are discussed. Furthermore, the potential challenges and prospects for energy-saving electrolysis and promotion of hydrogen production are examined. A comprehensive understanding of these strategies and their implications is important to the development of efficient and sustainable hydrogen production.

The ternary and additive strategy, introducing a third component into a binary blend and add suitable additives, opens a simple and promising avenue to improve the power conversion efficiency (PCE) of organic solar cells (OSCs). This study investigates the optimization of OSCs by introducing volatile additives and a third component, L8-BO-X, which tunes the active layer morphology and improves the performance of the devices. Utilizing various characterization techniques, such as the grazing-incidence wide-angle X-ray scattering (GIWAXS), film-depth-dependent light absorption spectroscopy (FLAS), and the femtosecond-resolved transient absorption (fsTA) spectroscopy, the effects of these adjustment on crystallinity, phase separation, exciton generation, and charge transport in photovoltaic device are explored. The incorporation of the third component and volatile additives results in less anisotropy in molecular orientation and thus faster exciton splitting at the D-A interface, enhanced π-π stacking coherence length and longer exciton lifetime, and eventually an enhanced power conversion efficiency (PCE) of 19.6 % (certified as 19.07 % in the National Institute of Metrology in China) and exceptional photostability, with the devices retaining 82 % efficiency after 1200 hours of continuous light exposure.

Resistive switching (RS) devices, often referred to as memristors, have exhibited interesting electronic performance that could be useful to enhance the capabilities of multiple types of integrated circuits that we use in our daily lives. However, RS devices still do not fulfil the reliability requirements of most commercial applications, mainly because the switching and failure mechanisms are still not fully understood. Density functional theory (DFT) and/or molecular dynamics (MD) are simulations used to describe complex interactions between groups of atoms, and they can be employed to clarify which physical, chemical, thermal and/or electronic phenomena take place during the normal operation of RS devices, which should help to enhance their performance and reliability. In this article, we review which studies have employed DFT and/or MD in the field of RS research, focusing on which methods have been employed and which material properties have been calculated. The goal of this article is not to delve into deep mathematical and computational issues – although some fundamental knowledge is presented – but to describe which type of simulations have been carried out and why they are useful in the field of RS research. This article helps to bridge the gap between the vast group of experimentalists working in the field of RS and computational scientists developing DFT and/or MD simulations.

Triterpenoids are natural bioactive compounds that demonstrate cytotoxic and chemopreventive activities by inhibiting various intracellular signals and transcription factors. Despite their efficacy, triterpenoid chemotherapeutics face significant challenges in cancer therapy because of their poor aqueous solubility, which restricts the utilization of potent drug variants. Consequently, there is a pressing need to develop a solubilized form of triterpenoid encapsulated within mechanically robust biomaterials, to facilitate injectable and minimally invasive delivery. In this study, we focused on ginsenoside compound K (CK), a natural pentacyclic triterpenoid. It was conjugated to hyaluronic acid (HA-CK) and employed as a novel guest molecule for binding to β-cyclodextrin-grafted hyaluronic acid (HA-βCD), which is the host polymer. This interaction resulted in the creation of an injectable supramolecular hydrogel (HG-Gel) through a straightforward mixing process involving host–guest interactions between βCD and CK. The physical properties of the hydrogels were easily manipulated by altering the molecular weight of HA and the grafting degree of βCD and CK in HA. Notably, the supramolecular hydrogel precursors exhibited excellent cell viability for normal cells, sparing over 80 % of NIH 3T3 and HaCaT cells. Intriguingly, these hydrogels facilitated effective delivery to CD44-overexpressing cancer cells, suppressing cell proliferation. Enhanced trafficking of CK to cancer cells heightened caspase-dependent apoptosis in B16F10 cells, with the extent of cell death contingent on the expression levels of CD44 in cancer cells. This effect of CK seems to be mediated through the induction of intracellular reactive oxygen species (ROS) and mitochondrial membrane potential loss. In melanoma tumor-bearing mouse models, HG-Gels effectively inhibited tumor growth. Importantly, no side effects were observed on normal tissues, underscoring the safety of naturally derived biomaterials. This study underscores the superiority of HG-Gels as a platform for utilizing triterpenoid saponins in melanoma therapy, suggesting their potential for enhancing the safety and efficacy of triterpenoids in cancer treatment.

Ultrafast UV photodetectors (UV PDs) are crucial components in modern optoelectronics because conventional detectors have reached a bottleneck with low integration, functionalities, and efficiency. Core-shell metal oxide nanobrushes (MOx NBs)-based UV PDs have enhanced the absorption, tunable performance, and good compatibility for diversified applications, including imaging, self-powered systems, remote communications, security, and wearable electronics. Core-shell PDs are developed with complex hierarchical or heterostructured configurations that encapsulate 1D MOx nanowires on 1D nanostructures (NSs) to transport high charge carrier mobility or efficiency by reducing scattering and recombination rates. This review presents a thorough development of MOx core-shell microstructure for the enhancement of detection response and stability with controlled parameters for multifunctional applications. Significant roles of MOx NBs-based UV PDs exploring various growth techniques and complex photodetection mechanisms with their challenges, limitations, and prospects, providing valuable insights for propelling the progression of photodetector technology in this comprehensive review are discussed meticulously. The novelty of MOx NBs-based UV PDs lies in their distinctive brush-like morphology aspect, tunable properties, and improved performance compared to other NSs, for rapid and sensitive response ( ̴µs-ms) under UV light illumination. The diverse photoresponse parameters and multifunctional applications of UV PDs incorporating MOx NBs are carefully summarized, which will set the roadmap for future photodetector technology.

Maintaining battery stability is the greatest concern for the next generation of electronic devices, such as automotive and foldable electronics. Advanced lithium batteries experience mechanical fracturing during cycling due to structural changes, reducing their lifespan. Self-healing properties can effectively mitigate this issue, thereby increasing the device's durability. Utilizing intrinsic self-healing polymers (SHPs) is a prevalent strategy, addressing mechanical defects and enhancing electrochemical properties independently. This review begins with a discussion of the SHPs and their various mechanisms of self-healing capability, followed by a presentation of approaches and their strategies for competing with Silicon-based, Li-Metal, and Li-Sulfur batteries. SHPs or binders have a high potential to deal with the critical problems of cracks and volume change problems. Also, it discussed promising methods for employing self-healing materials to combat integrity and stability obstacles. It provided an overview of boosting Li-adsorbing systems, de-lithiation behavior, extending cycle life, and high retention capacity based on the coverage and interlayer binding role, increasing diffusion, and enhancing cycle life. This work would encourage researchers to concentrate substantially on developing self-healing properties for designing high-energy and durable lithium batteries.

Electrically conductive coordination frameworks (ECCF) firmly anchored on renewable and sustainable alginate substrates are fundamentally important yet still challenging for flexible electronics. Herein, we report an interfacial self-assembly strategy to prepare alginate-anchored ECCF for constructing flexible and ultrastable light-gas dual sensors. By combining free Cu ions with trispectral linker, well-defined ECCF with a metal catechol structure (Cu-CAT) is directly grown on alginate fabrics (AF), which perfectly solves swelling problem of the hydrated alginate and improves flexibility and toughness of the electronic platform. By precisely tuning the thickness of as-prepared Cu-CAT nanowire film, the resultant AF/Cu-CAT sensor acts as not only a stable and self-powered light sensor in wide spectral range but also a selective NH₃ sensor operating at room temperature. Remarkably, the flexible sensor demonstrates light-gas synergistic effect, facilitating the adsorption-desorption kinetic by 358 % and thus achieving ultrafast and ultrastable response. This work provides a feasible approach for manufacturing ECCF-functionalized flexible organo-substrates and pushes forward a significant step toward the electric-field modulation of flexible sensors.

Electromagnetic interference has surged due to the widespread use of electronic communication technologies in integrated electrical systems. Traditionally, inflexible electromagnetic shielding materials have numerous drawbacks, such as being very brittle, uncomfortable to wear, and inappropriate for use in flexible applications. This review explores the advances in flexible (particularly stretchable and compressible) electromagnetic functional materials-based elastomers and a selection of the remarkable supporting deformable polymer matrixes. Additionally, it provides a comprehensive overview of the appropriate delicate structure and the associated manufacturing progress. Furthermore, it comprehensively outlines inventive uses of flexible shields in the fields of energy, sensing, mechanics, and communication, which extend far beyond electromagnetic protection, as well as their present state of development and prospects. Among them, we provide the first well-rounded overview of reconfigurable shielding devices and propose reconfigurability factors (r) and sensitivity (S) to quantify reconfigurable performance as well. This study diverges from prior studies that mostly concentrated on fulfilling conventional specifications (e.g., thin, lightweight, broad, and strong), and may be characterized as the future age of intelligent, adaptable, integrated shields.

Precisely tailoring the surface electronic state of catalysts to realize the optimal design of adsorption sites is essential to the surface-related gas-sensing reaction. Herein, based on both molecular orbital theory and p-band models, we develop a brilliant surface oxygen-injected method to simultaneously enhance the overlap of energy-level alignment (ELA) and reduce the anti-bonding filling (ABF) level between surface Bi p-band and adsorbed NO₂ molecule, leading to an optimal NO₂ adsorption mode and sensing performance. By controlling the oxygen permeation concentrations, the weak-oxidized Bi₂S₃-200 catalysts with ordered core/disordered shell configuration exhibit excellent NO₂ gas sensitivity (12.5 % to 1 ppm) and low experimental detection limit (100 ppb), surpassing that of most reported NO₂ sensors. Ex situ XPS characterizations further demonstrate that the weak-oxidized amorphous Bi species can serve as active adsorption centers to alter the electron transfer path in NO₂ atmosphere. Finally, through inserting flexible MEMS sensors array into multifunctional wireless sensing device, the Bi₂S₃-200 sensors can realize real-time NO₂/temperature/humidity monitoring and cloud data transmission at room temperature, which thereby pave the way for the development of crop health monitor and precision agriculture.