ABSTRACT Transition‐metal dichalcogenides (TMDs), with their layered structure, high specific surface area, and diverse phase transition properties, offer significant opportunities to tackle the challenges facing lithium–sulfur batteries (LSBs). The construction and phase engineering of TMDs have received sustained attention by numerous scholars, and various TMDs with diverse phases have been developed as electrode materials dedicated to further improving the electrochemical performance of LSBs. This review describes the structural features, synthesis strategies, and phase transition of TMDs, focusing on the phase transition of TMDs to systematically summarize the methods of phase transition, related mechanisms, and recent advancements in optimizing the electrochemical performance of TMDs applied to LSBs based on phase regulation. Future research should focus on providing a deeper understanding of phase transition mechanisms, enhancing crystal phase controllability and purity of TMDs, and designing composites with multifunctional materials to advance the comprehensive application of TMDs in energy storage systems.
ABSTRACT Developing selective and durable electrocatalysts remains a key challenge for the development of electrolyzers and unitized regenerative fuel cells (URFCs). Herein, we explore a novel approach toward specific reactions in water splitting, where one of the catalysts (Pt) is confined inside single‐wall carbon nanotubes (SWCNTs) for specific hydrogen evolution/oxidation reaction (HER/HOR), while the second catalyst (Ru/RuO x ) is located outside the SWCNTs for specific oxygen evolution reaction (OER), yielding a Pt@SWCNT@Ru catalyst with spatially separated inner and outer active sites. Encapsulation within SWCNTs also enhances Fe 3+ tolerance compared to Pt/C. Long‐term chronoamperometry reveals stable HER currents over 84 h and distinct Ru activation/decay kinetics over 72 h under acidic OER, while inductively coupled plasma optical emission spectroscopy shows no detectable Pt or Ru dissolution, indicating that spatial separation of Pt is likely to be preserved. These findings establish Pt@SWCNT@Ru as a proof‐of‐concept platform for spatially resolved, multifunctional electrodes relevant to next‑generation URFC architectures.
ABSTRACT Carbon‐electrode perovskite solar cells without hole transport layers (HTL‐free C‐PSCs) offer simple fabrication, low cost, and good environmental compatibility in photovoltaics. However, interfacial energy mismatch and severe non‐radiative recombination have long hindered their efficiency improvement. Here, we report a conductive metal‐organic framework (MOF) engineering strategy to improve performance of HTL‐free C‐PSCs by modifying the interface between the perovskite layer and the carbon electrode. A strong electron acceptor, 7,7,8,8‐tetracyanoquinodimethane (TCNQ), is incorporated within Cu 3 BTC 2 nanopores to form an intermolecular π–π conjugated network, turning the poorly conductive MOF into a functional layer that enables both defect passivation and efficient charge extraction. Abundant –COOH and –C≡N groups coordinate with uncoordinated Pb 2+ and I − , effectively passivating surface defects, reducing trap density, and suppressing non‐radiative recombination. Furthermore, by virtue of the improved energy‐level alignment at the perovskite–carbon interface and the reduced hole extraction barrier, this modifier significantly enhances charge separation and transport, thereby enabling the devices to achieve a high‐power conversion efficiency of 19.06%. HTL‐free C‐PSCs modified with TCNQ@Cu 3 BTC 2 show excellent long‐term stability, retaining 90.2% of initial efficiency after 1000 h in air without encapsulation and 91.6% after 1200 h of continuous illumination.
ABSTRACT The performance and commercial viability of proton exchange membrane fuel cells (PEMFCs) are constrained by key limitations in the membrane electrode assembly, including Nafion membrane swelling, low catalyst utilization, and inadequate water management in gas diffusion layers. Electrospinning has emerged as a promising technique for optimizing electrode components due to its unique capability to tailor fiber morphology, pore structure, and surface chemistry. Recent advances have incorporated artificial intelligence (AI) to assist in the design and optimization of porous materials, enabling efficient prediction of structural properties and performance. However, a systematic integration of AI into electrospinning processes to fabricate porous PEMFC components remains underdeveloped. This review comprehensively summarizes the application of electrospun materials in PEMFCs, emphasizing the structure–performance relationships in catalyst layers, gradient‐designed gas diffusion layers, and reinforced proton exchange membranes. Furthermore, it offers a forward‐looking perspective on the potential of AI‐assisted manufacturing strategies for advancing next‐generation high‐performance membrane electrodes.
ABSTRACT Metal‐organic frameworks (MOFs) have emerged as promising photocatalysts for solar‐to‐chemical energy conversion owing to their well‐defined architectures, tunable porosity, and tailorable coordination environments. However, conventional MOF photocatalysts are predominantly employed as components in composite materials, and direct structural modulation of MOFs themselves to boost photocatalytic performance remains challenging. Herein, a ligand‐defective Zr‐MOF was synthesized via a selective ligand‐pyrolysis strategy and applied to photocatalytic conversion of liquid biomass into biodiesel. The generated ligand defects exposed additional coordinatively unsaturated metal sites, modulated the band structure, and reduced excessive electron localization within the framework. These defects also regulated the coordination environment of Zr 4+ sites, enhanced charge‐transfer efficiency, and acted as carrier‐trapping sites to suppress electron–hole recombination. Comprehensive characterizations reveal that H‐UiO‐66‐N‐0.3 possesses optimized frameworks and electronic structures favorable for substrate adsorption and charge separation. As a result, it achieved a biodiesel yield of 98.5% in the photocatalytic (trans)esterification reaction, with a rate constant 34 times higher than that of pristine UiO‐66. Collectively, this work realizes synergistic modulation of defect density, electronic structure, and catalytic activity via precise defect‐engineering, thereby providing a potentially viable design strategy to advance the application of MOFs in sustainable biomass transformation.
