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The development of novel nano-single-atom-site catalysts with optimized electron configurations and active water adsorption (^*H₂O) to release hydrogen protons (^*H) is paramount for photocatalytic hydrogen evolution (PHE), a multi-step reaction process involving two electrons. In this study, an atom-confinement and thermal reduction strategy is introduced to achieve synergistic Ag single-atoms (Ag₁) and nanoparticles (Ag_NPs) confined within carbon nitride nanotubes (Ag_1+NPs-CN) for enhanced photocatalytic hydrogen evolution. Mechanistic investigations reveal that H₂O adsorption/dissociation predominantly occurs at Ag₁ sites, while Ag_NPs sites notably facilitate H₂ release, indicating the synergistic effect between Ag₁ and Ag_NPs in the H₂ evolution reaction. Furthermore, the effective confining of Ag species is beneficial for trapping electrons in highly active reaction regions, while the "electronic metal-support interactions" (EMSIs) of Ag_NPs and Ag₁-C₂N sites regulate the d-band centers and effectively optimize the adsorption/desorption of intermediates in photocatalytic hydrogen evolution, leading to enhanced H₂ production performance. This work demonstrates the potential of the construction of synergistic photocatalysts for efficient energy conversion and storage; Hydrogen production; Nanoparticles; Photocatalysis; Single atom; and Synergistic effect.

The rise in global temperatures and environmental contamination resulting from traditional fossil fuel usage has prompted a search for alternative energy sources. Utilizing solar energy to drive the direct splitting of water for hydrogen production has emerged as a promising solution to these challenges. Covalent organic frameworks (COFs) are ordered, crystalline materials made up of organic molecules linked by covalent bonds, featuring permanent porosity and a wide range of structural topologies. COFs serve as suitable platforms for solar-driven water splitting to produce hydrogen, as their building blocks can be tailored to possess adjustable band gaps, charge separation capabilities, porosity, wettability, and chemical stability. Here, the impact of the interface in the context of the photocatalytic reaction is focused and propose strategies to enhance the hydrogen production performance of COFs photocatalysis. In particular, how hybrid photocatalytic interfaces affect photocatalytic performance is focused.

The escalating demand for high-power and compact-size advanced electronic devices and power systems necessitates polymers to exhibit superior electrical properties even under harsh environments. However, reconciling the seemingly contradictory attributes of excellent electrical properties and thermal stability poses a formidable challenge for current epoxy polymer (EP) materials and their applications. To meet the need, here two classes of bi-aryl diamine curing agents are described that enable polymers to exhibit well-balanced thermal and dielectric properties with functional bridging groups. A weak conjugation system in highly thermally stable polymers with an aromatic backbone is constructed, using electron-modulating bridging groups to immobilize intramolecular free carriers by tailoring trap sites, and bulky bridging groups to prevent molecular stacking to inhibit intermolecular charge transport. The resultant polymer exhibits a volume resistance of 7.45 × 10¹² Ω m and a direct current breakdown strength of 368.74 kV mm^-1 at 120 °C, which are 2.2 and 2.4 times higher than that of commercial anhydride-cured EP, respectively. It is demonstrated to be due to the inhibition of charge injection and transport. The proposed aromatic amine multimolecule approach, combined with diverse functional bridging groups, is a promising direction for exploring next-generation EP insulation materials suitable for extreme conditions.

Silicon (Si) is a promising anode material for next-generation lithium-ion batteries (LIBs) due to its high specific capacity and abundance. However, challenges such as significant volume expansion during cycling and poor electrical conductivity hinder its large-scale application. In this study, the multifunction of sodium polyacrylate (PAAS) utilized to develop a hierarchical porous silicon-carbon anode (Si/SiO_x@C) through a simple and efficient method. The hierarchical porous structure successively consists of nano-silicon cores, SiO_x encapsulating layers, surrounding space, and phenolic resin-derived carbon shells with carbon chains connecting the SiO_x layers and carbon shells in the space. The SiO_x nanolayers promote Li⁺ transport, while excess PAAS, removed by washing, generates space for volume expansion, improving cycling performance. Residual carbon chains of PAAS and carbon shells form a conducting carbon network, enhancing electron transport and rate performance. As an anode for LIBs, the composite delivers a high reversible capacity of 685.3 mAh g⁻¹ after 1000 cycles at 1 C with a capacity retention rate of 54.7%. Full cells with the Si/SiO_x@C anode and LiNi_0.8Co_0.1Mn_0.1O₂ cathode exhibit an excellent capacity retention rate of 96.8% after 200 cycles at 1 C. This work provides a novel approach for the rational design and engineering of advanced LIBs.

The use of efficient and affordable non-precious metal catalysts for hydrogen and oxygen evolution reactions is vital for replacing and widely implementing new energy sources. Nevertheless, improving the catalytic performance of these non-precious-metal bifunctional electrocatalysts continues to be a major challenge. In this article, an optimized Se-incorporated bulk CoS₂@MoS₂ heterostructure grown on the surface of carbon nanotubes is reported. The resulting Se-CoS₂@MoS₂/CNTs exhibit robust bifunctional electrocatalytic performance, with low overpotentials of 85 and 240 mV @ 10 mA·cm^-2 for HER and OER, respectively. The materials exhibit superior long-term stability of over 145 h, surpassing most electrocatalysts of similar type. This enhanced performance is attributed to the synergistic effect at the interface between the MoS₂ and CoS₂ phases, abundant active sites, and high active surface area, which collectively improves the electron-transfer efficiency during the reaction process. Furthermore, the incorporation of the amorphous state of Se into the heterostructure yields a change in the crystallinity of the heterostructure in the electronic structure, which optimizes the adsorption and activation energy barriers of the catalytic intermediate. This study thus presents a promising approach to regulating anion doping in bifunctional electrocatalysts.

Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) is widely utilized as the hole transport layer (HTL) inorganic photovoltaics (OPVs) because of its low-temperature solution processing peculiarity, high optical transmittance, and excellent mechanical flexibility. However, the core-shell structure of PSS coated PEDOT results in relatively low conductivity, work function, transmittance and waterproofness of PEDOT:PSS interlayer, limiting the photovoltaic performance and stability of OPVs. Here, the conformation of PEDOT chains are regulated from helical benzoyl to linear quinone structure via incorporation of 2D Cd_0.85PS₃Li_0.15H_0.15dopant into the conventional PEDOT:PSS interlayer, promoting an interpenetrating network structure in PEDOT:PSS interlayer and forming an efficient hole transport channel from active layer to ITO electrode. Such features significantly improve the electrical conductivity, work function, and transmittance of PEDOT:PSS interlayer. In consequence, the maximum power conversion efficiency (PCE) of D18:L8-BO, PBDB-T:ITIC, as well as PTzBI-dF:L8-BO based OPVs ameliorated from 18.37%, 8.94%, and 15.80% to 19.26%, 10.00%, and 16.83%, respectively. The application of Cd_0.85PS₃Li_0.15H_0.15 doping PEDOT:PSS strategy demonstrates great potential for the development of strongly conductive, large-work-function, highly transparent, and excellent-waterproof PEDOT:PSS interlayer toward highly efficient and stable OPVs.

Heteroatom doping is the most common means to enhance the Li⁺/Na⁺ ions storage of hard carbon (HC). The explanation of the storage mechanism of heteroatom-doped HC is to increase the active site or widen the layer spacing while ignoring the effect of local bending structure induced by it. Meanwhile, the storage mechanism by the localized bending structure also lacks in-depth study. Herein, a locally curved configuration and an amorphous structure are designed by introducing different heteroatoms, respectively, and the mechanism of the two types of structures on the Li⁺/Na⁺ ions storage is explored. The density functional theory (DFT) calculation shows that the adsorption energy of Li⁺/Na⁺ ions is optimal at the appropriate curvature of 27.72 m^-1. Serving as anode for lithium/sodium ion batteries in ester electrolytes, the optimized HCs demonstrate satisfied specific capacity and high-rate capability, respectively. Furthermore, the charging capacity below 1.0 V of HC with suitable curvature microstructure reaches 84.8% and 90.1% of the total charge capacity, confirming that the curvature defects can better control the delithiation/desodiation process, and provide a higher energy density. This study enlightens new insights into the storage mechanisms of Li⁺/Na⁺ ions and provides guidance for better design of heteroatom-doped carbon anodes with superior performance.

In recent years, the performance of metal halide perovskite (MHP)-based detectors (photon, biomedical, and X-ray detection) has significantly improved, resulting in higher carrier mobilities, longer carrier diffusion lengths, and excellent absorption coefficients. However, the widespread adoption of halide perovskites has been hindered by issues related to their stability and toxicity. Various strategies have been adopted to address these challenges, focusing on enhancing ambient stability and reducing toxicity by encapsulating MHPs within stable and robust host materials, such as silicon compounds, metal oxides, chalcogenides, and lead-free perovskites. This review focuses on recent developments in hybrid nanostructure-based detectors (photon, biomedical, and X-ray), particularly core/shell architectures, and provides a comprehensive analysis of techniques for mitigating degradation due to light and oxygen exposure, UV irradiance, and thermal effects. This review enhances the understanding of current advancements in core/shell-based detectors.

Water electrolysis powered by renewable energy is a green and sustainable method for hydrogen production. Decoupled water electrolysis with the aid of solid-state redox mediator could separate the hydrogen and oxygen production in time and space without the use of the membrane, showing high flexibility. Herein, a MoO₃ electrode with fast proton transport property is employed as a solid-state redox mediator to construct a membrane-free decoupled acidic electrolytic system. The MoO₃ electrode exhibits high specific capacity (204.3 mAh g^-1 at 5 A g^-1) and excellent rate performance (92.8 mAh g^-1 at 150 A g^-1) in the acidic environment. Due to the dense oxide-ion arrays, MoO₃ still exhibits excellent performance under high mass-loading. In addition, a hybrid decoupled electrolysis system is also constructed by combining water reduction and hydrazine oxidation, which can not only generate high-purity H₂ but also remove hydrazine hazards in acidic wastewater with lower energy consumption.

Due to their substantial energy density, rapid charging and discharging rates, and extended lifespan, lithium-ion batteries have attained broad application across various industries. However, their limited theoretical capacity struggles to meet the growing demand for battery capacity in consumer electronics, automotive, and aerospace applications. As a promising substitute, solid-state lithium-metal batteries (SSLBs) have emerged, utilizing a lithium-metal anode that boasts a significant theoretical specific capacity and non-flammable solid-state electrolytes (SSEs) to address energy density limitations and safety concerns. For SSLBs to attain large-scale commercial viability, SSEs require heightened ionic-conductivity, improved mechanical characteristics, and enhanced chemical and electrochemical stability. Furthermore, tackling the challenges related to interfacial contacts between SSEs and the lithium-metal anode is imperative. This review comprehensively overviews the primary methods used to prepare garnet SSEs and summarizes doping strategies for various sites on Li₇La₃Zr₂O₁₂ (LLZO) garnet SSEs, aiming to optimize the crystal phase to achieve more favorable properties in SSE applications. Additionally, it discusses strategies for modifying the interfacial contact between the lithium-metal anode and SSEs, classifying them into three areas: surface modification, interlayer-modification, and composite anodes. This review aims to serve as a valuable reference for future researchers working on high-performance garnet SSEs and effective interfacial-modification strategies.