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Functional Transformation of Four-Bladed Rylene Propellers Utilizing Non-Metal and d <sup>8</sup> Metal Core Shifting Strategy: Significant Impact on Photovoltaic Performance and Electrocatalytic Hydrogen Evolution Activity
摘要： Two kinds of four-bladed perylene diimide (PDI) propellers with d8 metal and non-metal cores are efficiently synthesized. The Ni-PDI, Pd-PDI, and Pt-PDI propellers, equipped with d8 metal cores, have two absorption bands at 350-650 nm and 780-1200 nm with deep LUMO levels of -4.40 eV to -4.51 eV. The TTF-PDI, QU-PDI, and PH-PDI propellers with non-metal cores have only one absorption band at 350-650 nm with upshifted LUMO levels. Interestingly, the organic photovoltaic (OPV) results show that reducing the intramolecular charge traps between the blade and core subunits of the PDI propellers can effectively improve the power conversion efficiency (PCE). The device based on the QU-PDI acceptor exhibits a PCE that is up to more than 300 times higher (9.33%) than that of the d8 metal core PDI propellers (Pd-PDI, PCE=0.03%), which is one of the best photovoltaic performances with an excellent fill factor (FF=71.8%) exhibited by PDI-derivative acceptors. Conversely, the electro-catalytic H2 evolution activity of Pt-PDI (current destiny =10.00 mA/cm2 at -0.377 V), which exhibited a record performance for PDI-based catalysts to date, is up to 1000 times greater than that of the non-metal core PDI propellers (QU-PDI, 0.01 mA/cm2 at -0.377 V). Our results indicate that both highly efficient OPV and electrochemical H2 evolution catalysts can be achieved via the rational functionalization of PDI propellers with non-metal and d8 metal cores.
关键词： d8 metal cores,electrocatalytic hydrogen evolution,non-metal cores,organic photovoltaic (OPV),perylene diimide (PDI)
更新于2025-09-16 10:30:52
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Electric field-assisted synthesis of Pt, carbon quantum dots-coloaded graphene hybrid for hydrogen evolution reaction
摘要： A simple method for preparation of Pt, CQDs-coloaded graphene composite for hydrogen evolution reaction (HER) is established by electrolysis-solvothermal process. Graphene is obtained by electrochemical exfoliation of graphite in cathode, while carbon quantum dots (CQDs) and Pt nanoparticles (NPs) are in-situ generated in the electrolyte simultaneously. CQDs are evolved from propylene carbonate solvent and Pt NPs are derived from reduction of Pt intermediate species generated from anodic dissolution of Pt counter electrode during electrolysis process. Then Pt NPs and CQDs are well dispersed on graphene at subsequent solvothermal process. Work voltage and electrolyte type as the key electrolysis conditions are applied to control the concentration of CQDs and Pt NPs, which decides electrochemically active surface area and HER activity of obtained catalysts. Significantly, the obtained superior catalyst with trace amount of Pt (0.145 wt%), shows markedly enhanced catalytic HER activity with mass activity of 37.5 A mg?1 at ?50 mV in acidic solution, 68.2 times more active than Pt/C. This study provides a universal and promising methodology for synthesizing Pt, CQDs coloaded hybrid with the assistance of electric field as cost-effective catalysts for fuel cells.
关键词： Pt nanoparticles,Carbon quantum dots,Graphene,Hydrogen evolution reaction
更新于2025-09-16 10:30:52
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Charge Transfer Engineering via Multiple Heteroatom Doping in Dual Carbon-Coupled Cobalt Phosphides for Highly Efficient Overall Water Splitting
摘要： The exploration of non-noble-metal bifunctional electrocatalysts with high activity and stability for overall water splitting is crucial, but remains challenging for hydrogen fuel production. Herein, tuning of the charge transfer ability and catalytic performance of zeolitic imidazolate framework-derived porous carbon/reduced graphene oxide-coupled CoP composites (CoP@C@rGO) was achieved by incorporating multiple heteroatoms. The combined experimental investigation and density functional theory calculations revealed that the electronic interaction within the composites caused by B, N, and S tri-doped heteroatoms effectively induced interfacial charge transfer, which improved the active site accessibility and reduced the energy barriers of the evolution reaction; water splitting intermediates. From the synergetic effects of the components, the overall water splitting electrolyzer assembled using the newly prepared B,N,S-CoP@C@rGO catalyst required only 1.50 V to drive a current density of 10 mA cm–2, which is superior to the commercial Pt/C and IrO2/C couple (1.56 V).
关键词： hydrogen evolution reaction,oxygen evolution reaction,multiple doping,overall water splitting,charge transfer
更新于2025-09-12 10:27:22
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A nanoreactor based on SrTiO3 coupled TiO2 nanotubes confined Au nanoparticles for photocatalytic hydrogen evolution
摘要： A TiO2 nanotube-based nanoreactor was designed and fabricated by facile two steps synthesis: firstly, hydrothermal synthesized SrTiO3 was deposited on TiO2 nanotubes (TiO2NTs). Secondly, the Au nanoparticles (NPs) were encapsulated inside the TiO2NTs followed by vacuum-assisted impregnation. The as-synthesized composites were characterized using Transmission electron microscopy (TEM), X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Photoluminescence spectra (PL) and Ultravioletevisible absorption spectroscopy (UVevis). The photocatalytic performance was evaluated by the hydrogen evolution reaction. The results revealed that the SrTiO3 modified TiO2NTs confined Au NPs (STO-TiO2NTs@Au) achieved an enhanced hydrogen evolution rate at 7200 mmol h?1 g?1, which was 2.2 times higher than that of bald TiO2NTs@Au at 3300 mmol h?1 g?1. The improved photocatalytic activity could be attributed to the synergistic effect of the electron-donating of SrTiO3 and TiO2NTs confinement. The as-designed nanoreactor structure provides an example of efficient carriers’ separation photocatalyst.
关键词： Au nanoparticles,Confinement,SrTiO3,TiO2 nanotubes,Photocatalytic hydrogen evolution
更新于2025-09-12 10:27:22
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Type-II heterostructures of <b>α</b> -V <sub/>2</sub> O <sub/>5</sub> nanowires interfaced with cadmium chalcogenide quantum dots: Programmable energetic offsets, ultrafast charge transfer, and photocatalytic hydrogen evolution
摘要： We synthesized a new class of heterostructures by depositing CdS, CdSe, or CdTe quantum dots (QDs) onto α-V2O5 nanowires (NWs) via either successive ionic layer adsorption and reaction (SILAR) or linker-assisted assembly (LAA). SILAR yielded the highest loadings of QDs per NW, whereas LAA enabled better control over the size and properties of QDs. Soft and hard x-ray photoelectron spectroscopy in conjunction with density functional theory calculations revealed that all α-V2O5/QD heterostructures exhibited Type-II band offset energetics, with a staggered gap where the conduction- and valence-band edges of α-V2O5 NWs lie at lower energies (relative to the vacuum level) than their QD counterparts. Transient absorption spectroscopy measurements revealed that the Type-II energetic offsets promoted the ultrafast (10?12–10?11 s) separation of photogenerated electrons and holes across the NW/QD interface to yield long-lived (10?6 s) charge-separated states. Charge-transfer dynamics and charge-recombination time scales varied subtly with the composition of heterostructures and the nature of the NW/QD interface, with both charge separation and recombination occurring more rapidly within SILAR-derived heterostructures. LAA-derived α-V2O5/CdSe heterostructures promoted the photocatalytic reduction of aqueous protons to H2 with a 20-fold or greater enhancement relative to isolated colloidal CdSe QDs or dispersed α-V2O5 NWs. The separation of photoexcited electrons and holes across the NW/QD interface could thus be exploited in redox photocatalysis. In light of their programmable compositions and properties and their Type-II energetics that drive ultrafast charge separation, the α-V2O5/QD heterostructures are a promising new class of photocatalyst architectures ripe for continued exploration.
关键词： α-V2O5 nanowires,cadmium chalcogenide quantum dots,photocatalytic hydrogen evolution,programmable energetic offsets,Type-II heterostructures,ultrafast charge transfer
更新于2025-09-12 10:27:22
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High photoresponse and fast carrier mobility: Two‐dimensional rGO‐AgBr/Ag composite based on Z‐scheme heterointerface with plasma for hydrogen evolution
摘要： With the improvement of people's living standard, energy shortage is increasingly severe. Photocatalysis technology is one of the most effective means to solve this problem. Generally, poor visible‐light response and fast combination of photo‐induced carriers are the main limiting factors to traditional photocatalysts. Aiming at this problem, in this paper, AgBr was used as the photosensitizer to immobilize on the surface of reduced graphene oxide (rGO) for the complexation of Ag+ ions and carboxyl groups of precursor graphene oxide (GO), then the two‐dimensional rGO‐AgBr/Ag composites (2D rGAA‐α, α = 1, 2 and 3) were synthesized by solvothermal method. The structures, morphologies, chemical bonding states and photoelectrochemical properties of the samples were analyzed to study the samples, and the corresponding visible‐light‐driven (VLD) catalytic performances were studied by hydrogen evolution reaction (HER). Compared with pure rGO, the light absorption of rGAA‐α was almost extended to full spectral range for the Z‐scheme heterointerface (rGO‐AgBr) construction, and the separation of photo‐induced carriers can be promoted effectively. The HER results showed that the average hydrogen evolution rate ( Rp) of rGAA‐α was significantly increased, and the rGAA‐2 catalyst presented the highest Rp (72.71 μmol ‐1). After six recycling experiments, the very faint activity decrease and ‐1g h unobvious structure change suggested the high photostability. Accordingly, the enhanced catalytic activity of rGAA‐α catalysts was attributed to the formation of Z‐scheme heterointerface and generation of Ag plasmas, so this study will provide a simple, effective and promising method for hydrogen energy development.
关键词： AgBr,heterostructure,Ag plasma,hydrogen evolution,reduced graphene oxide
更新于2025-09-12 10:27:22
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Enhanced photocatalytic hydrogen evolution over TiO2/g-C3N4 2D heterojunction coupled with plasmon Ag nanoparticles
摘要： 2D heterojunction based on g-C3N4 nanosheets with other semiconductor nanosheets is a promising way to improve photocatalytic hydrogen evolution (PHE) activity over g-C3N4. However, current 2D heterojunction based on g-C3N4 are unsatisfactory due to their insu?cient absorption of visible light and ine?cient charge separation. In this work, Ag/TiO2/g-C3N4 nanocomposites based on 2D heterojunction coupling with Ag surface plasmon resonance (SPR) were synthesized by a method combining facile wetness impregnation calcination. The PHE activity of Ag/TiO2/g-C3N4 nanocomposites is attributed to the TiO2/g-C3N4 2D heterojunction and bare g-C3N4 nanosheet under visible light irradiation, indicating a cooperative e?ect between Ag and TiO2/g-C3N4 2D heterojunction. As a result of SPR e?ect, the composites strongly absorb visible light. In addition, the oscillating hot electrons from Ag can easily transfer to 2D heterojunction. This synergistic e?ect lead to su?cient visible light absorption and e?cient charge separation of 2D heterojunction, which improved the PHE activity of g-C3N4. This work indicates that loading metal nanoparticles on 2D heterojunction as metal SPR-2D heterojunction nanocomposites may be a potential method for harvesting visible light for PHE.
关键词： Surface plasmon resonance,Photocatalytic hydrogen evolution,TiO2,2D heterojunction,g-C3N4
更新于2025-09-12 10:27:22
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MoSx quantum dots modified black silicon for high efficient photoelectrochemical hydrogen evolution
摘要： Nanostructured black silicon (bSi) is widely used for solar water splitting application due to the excellent light-harvesting properties and large surface area-to-volume ratio that favors photoelectrochemical reactions. However, bSi suffers from low catalytic activity, owing to its poor charge transfer kinetics during hydrogen evolution process. In this work, we developed a novel photoelectrode by incorporating molybdenum sulfide (MoSx) quantum dots on the surface of black silicon. The synergetic effect of MoSx and bSi significantly enhance the activity for hydrogen evolution reaction. An onset potential of 0.255 VRHE, a high short-circuit photocurrent density (Jsc) of 12.2 mA·cm-2, and a hydrogen evolution rate of 226.5 μmol·h-1·cm-2 have been achieved.
关键词： photocathode,Black silicon,MoSx quantum dots,hydrogen evolution reaction
更新于2025-09-12 10:27:22
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Controlled Micro/Nanodome Formation in Proton‐Irradiated Bulk Transition‐Metal Dichalcogenides
摘要： At the few-atom-thick limit, transition-metal dichalcogenides (TMDs) exhibit strongly interconnected structural and optoelectronic properties. The possibility to tailor the latter by controlling the former is expected to have a great impact on applied and fundamental research. As shown here, proton irradiation deeply affects the surface morphology of bulk TMD crystals. Protons penetrate the top layer, resulting in the production and progressive accumulation of molecular hydrogen in the first interlayer region. This leads to the blistering of one-monolayer thick domes, which stud the crystal surface and locally turn the dark bulk material into an efficient light emitter. The domes are stable (>2-year lifetime) and robust, and host strong, complex strain fields. Lithographic techniques provide a means to engineer the formation process so that the domes can be produced with well-ordered positions and sizes tunable from the nanometer to the micrometer scale, with important prospects for so far unattainable applications.
关键词： transition-metal dichalcogenides,hydrogen evolution reaction,strain,photoluminescence,2D materials,Raman
更新于2025-09-11 14:15:04
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Proton-Coupled Electron Transfer Kinetics for the Photoinduced Generation of a Cobalt(III)-Hydride Complex
摘要： Studying the formation of transition metal hydride complexes via proton-coupled electron transfer is important for developing next-generation molecular catalysts for hydrogen evolution. We report herein the study of stepwise photoinduced reduction and protonation of [CoIICp-(dppe)]+ (Cp = cyclopentadienyl, dppe = 1,2-bis-(diphenylphosphino)ethane) to form the corresponding hydride complex [HCoIIICp(dppe)]+. Reaction intermediates were optically tracked using transient absorption spectroscopy, and a combination of experimental fitting and kinetic simulations was used to determine apparent rate constants for electron transfer and proton transfer with a range of acid sources. A linear free energy relationship is observed between measured apparent proton transfer rate constants and acid strength, but marked differences from previously electrochemically determined protonation rate constants are found. These deviations, which stem from ground-state reactivity present in photochemical experiments, highlight the challenges in comparing mechanistic studies using different techniques.
关键词： kinetic simulations,transient absorption spectroscopy,transition metal hydride complexes,proton-coupled electron transfer,hydrogen evolution
更新于2025-09-11 14:15:04