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.
ABSTRACT The performance of photoanodes in photoelectrocatalytic (PEC) water splitting is limited by sluggish surface oxygen evolution reaction (OER) kinetics. Herein, a multifunctional p‐n heterojunction NiFe‐layered double hydroxide/CoS (NiFe‐LDH/CoS), acted as an oxygen evolution co‐catalyst (OECs), is introduced on BiVO 4 photoanodes for enhanced PEC performance. The formation of the p‐n heterojunction with CoS results in a positively charged NiFe‐LDH, thereby promoting the OER activity. Meanwhile, the p‐n heterojunction between CoS and BiVO 4 facilitates interfacial charge transport. Moreover, the PEC water oxidation process can be further modified via the photothermal effect of CoS. Due to the collective properties of p‐n heterojunction NiFe‐LDH/CoS cocatalysts, the obtained NiFe‐LDH/CoS/BiVO 4 photoanodes achieved a record photocurrent density of 6.97 mA cm −2 at 1.23 V versus reversible hydrogen electrode (RHE) assisted by near‐infrared light. These findings provide new insight into the rational regulating of surface reaction kinetics and cocatalyst/photoanode interface charge transfer simultaneously.
ABSTRACT Flexible optical materials with switchable multichannel outputs are highly desirable for advanced anti‐counterfeiting and information security applications; yet, it remains challenging to integrate photochromism, luminescence, and mechanical robustness into a single platform. Here, we report a photo‐switchable luminescent composite film by incorporating a terbium complex donor (Tb‐Phen) and a spiropyran derivative acceptor (SP‐OH) into a polyurethane matrix. The dual‐ligand Tb‐Phen complex shows strong green emission, high quantum yield, and good stability, whereas SP‐OH provides reversible photochromic conversion. Upon UV irradiation, SP‐OH is transformed into its merocyanine form, which activates an efficient fluorescence resonance energy transfer (FRET) process from Tb‐Phen to the acceptor, leading to pronounced quenching of green emission and emergence of a red emission channel. The optimized composite film shows a high FRET efficiency of 80.7%, a tensile strength of 20.12 MPa, an elongation at break of 494%, good thermal stability, and stable reversible switching behavior under repeated UV/visible‐light cycles. Benefiting from the coupled photochromic and luminescent responses, the film enables multilevel anti‐counterfeiting, wavelength‐selective information encryption, and rewritable optical data storage. This work provides an effective strategy for constructing flexible photo‐responsive FRET materials with integrated optical and mechanical functions.
