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Fast Photoelectric Conversion in the Near‐Infrared Enabled by Plasmon‐Induced Hot‐Electron Transfer
摘要： Interfacial charge transfer is a fundamental and crucial process in photoelectric conversion. If charge transfer is not fast enough, carrier harvesting can compromise with competitive relaxation pathways, e.g., cooling, trapping, and recombination. Some of these processes can strongly affect the speed and efficiency of photoelectric conversion. In this work, it is elaborated that plasmon-induced hot-electron transfer (HET) from tungsten suboxide to graphene is a sufficiently fast process to prevent carrier cooling and trapping processes. A fast near-infrared detector empowered by HET is demonstrated, and the response time is three orders of magnitude faster than that based on common band-edge electron transfer. Moreover, HET can overcome the spectral limit of the bandgap of tungsten suboxide (≈2.8 eV) to extent the photo-response to the communication band of 1550 nm (≈0.8 eV). These results indicate that plasmon-induced HET is a new strategy for implementation of efficient and high-speed photoelectric devices.
关键词： localized surface plasmon resonance,infrared photodetection,photoelectric conversion,hot-electron transfer,graphene
更新于2025-09-11 14:15:04
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Design and synthesis of benzimidazole phenol-porphyrin dyads for the study of bioinspired photoinduced proton-coupled electron transfer
摘要： Benzimidazole phenol-porphyrin dyads have been synthesized to study proton-coupled electron transfer (PCET) reactions induced by photoexcitation. High-potential porphyrins have been chosen to model P680, the photoactive chlorophyll cluster of photosynthetic photosystem II (PSII). They have either two or three pentafluorophenyl groups at the meso positions to impart the high redox potential. The benzimidazole phenol (BIP) moiety models the Tyrz-His190 pair of PSII, which is a redox mediator that shuttles electrons from the water oxidation catalyst to P680?+. The dyads consisting of a porphyrin and an unsubstituted BIP are designed to study one-electron one-proton transfer (E1PT) processes upon excitation of the porphyrin. When the BIP moiety is substituted with proton-accepting groups such as imines, one-electron two-proton transfer (E2PT) processes are expected to take place upon oxidation of the phenol by the excited state of the porphyrin. The bis-pentafluorophenyl porphyrins linked to BIPs provide platforms for introducing a variety of electron-accepting moieties and/or anchoring groups to attach semiconductor nanoparticles to the macrocycle. The triads thus formed will serve to study the PCET process involving the BIPs when the oxidation of the phenol is achieved by the photochemically produced radical cation of the porphyrin.
关键词： pentafluorophenyl porphyrin,benzimidazole derivatives,proton-coupled electron transfer (PCET),photosystem II
更新于2025-09-11 14:15:04
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Overall water splitting and hydrogen peroxide synthesis by gold nanoparticle-based plasmonic photocatalysts
摘要： Gold nanoparticle-based plasmonic photocatalysts can be driven by excitation of the localized surface plasmon resonance. Among them, hot-electron transfer-type photocatalysts have recently attracted interest as promising solar-to-chemical converters owing to the wide spectral response from visible-to-infrared light. This Minireview highlights recent studies on two kinds of artificial photosynthesis - water splitting and H2O2 synthesis from water and oxygen - using hot-electron transfer-type plasmonic photocatalysts with particular emphasis placed on the electrocatalysis of Au nanoparticles.
关键词： water splitting,gold nanoparticle,hot-electron transfer,hydrogen peroxide synthesis,plasmonic photocatalysts
更新于2025-09-11 14:15:04
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Bioelectrochemical Interface Engineering || Biophotovoltaics
摘要： The expeditious increase in population, the furtherance of people’s lifestyles, and the liability to nurture the needs of growing populations critically demand the exploration of prodigious energy devices with remarkable potentials to meet the current massive energy demand and address great environmental concerns (Angelaalincy et al. 2018). Among the widely established alternative and renewable energy sources, fuel cells have been considered as one of the most significant energy devices, owing to their ability to generate and store energy with high efficiency and at affordable costs with trivial greenhouse emissions (Senthilkumar et al. 2018). Moreover, fuel cells have been in existence for ages and are undergoing rapid evolutionary changes with thriving technological advancements. The history of biofuel cells dates back to the early eighteenth century, and this technology became so captivating then that many researchers started experimenting and publishing results on fuel cells in the following years. However, the actual microbial fuel cell (MFC) employing pure cultures of bacteria was successfully demonstrated in the 1980s by H. Peter Bennetto (Bennetto et al. 1980).
关键词： Electron transfer mechanisms,Microbial solar cells,Fuel cell–solar cell hybrids,Biophotovoltaics,Photosynthetic microbial fuel cells
更新于2025-09-11 14:15:04
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Dinitrogen Reduction to Ammonium at Rhenium Utilizing Light and Proton-Coupled Electron Transfer
摘要： The direct scission of the triple bond of dinitrogen (N2) by a metal complex is an alluring entry point into the transformation of N2 to ammonia (NH3) in molecular catalysis. Reported herein is a pincer-ligated rhenium system that reduces N2 to NH3 via a well-defined reaction sequence involving reductive formation of a bridging N2 complex, photolytic N2 splitting, and proton-coupled electron transfer (PCET) reduction of the metal-nitride bond. The new complex (PONOP)ReCl3 (PONOP = 2,6-bis(diisopropylphosphinito)pyridine) is reduced under N2 to afford the trans,trans-isomer of the bimetallic complex [(PONOP)ReCl2]2(μ-N2) as an isolable kinetic product that isomerizes sequentially upon heating into the trans,cis and cis,cis isomers. All isomers are inert to thermal N2 scission, and the trans,trans-isomer is also inert to photolytic N2 cleavage. In striking contrast, illumination of the trans,cis and cis,cis-isomers with blue light (405 nm) affords the octahedral nitride complex cis-(PONOP)Re(N)Cl2 in 47% spectroscopic yield and 11% quantum yield. The photon energy drives an N2 splitting reaction that is thermodynamically unfavorable under standard conditions, producing a nitrido complex that reacts with SmI2/H2O to produce a rhenium tetrahydride complex (38% yield) and furnish ammonia in 74% yield.
关键词： light,dinitrogen reduction,ammonium,proton-coupled electron transfer,rhenium
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
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Investigation of photo-induced electron transfer between amino-functionalized graphene quantum dots and selenium nanoparticle and it's application for sensitive fluorescent detection of copper ions
摘要： Copper ions play an essential role in some biological processes. Currently, there is a need for the development of convenient and reliable analytical methods for the Cu2+ measurement. In the present work, a sensitive fluorescence method was developed for the determination of copper ions. Amino-functionalized graphene quantum dots (af-GQDs) and selenium nanoparticles (Se NPs) were synthetized, respectively, and they were characterized via transmission electron microscope, infrared spectrum analysis and X-ray photoelectron spectrum measurement. Photo-induced electron transfer (PET) between the prepared two nanomaterials could effectively quench the fluorescence of af-GQDs. Cu(II) was reduced to Cu(I) in the presence ascorbic acid and Cu2Se was finally generated on Se NPs surface, which led to the declined PET efficiency and inhibited the fluorescence quenching of af-GQDs. The change in fluorescence intensity was linearly correlated to the logarithm of the Cu2+ concentration from 1 nM to 10 μM, with a detection limit of 0.4 nM under the optimal conditions. The detections of copper ions in water samples were realized via standard addition method and the recovery values varied from 98.7% to 103%. The proposed fluorescence method was also employed to analyze the uptake of Cu2+ into human cervical carcinoma HeLa cells and cisplatin-resistant HeLa cells (HeLa/DDP cells). The experimental results indicate that the decreased hCTR1 expression level in HeLa/DDP cells weakened the uptake of copper ions into these drug-resistant tumor cells.
关键词： photo-induced electron transfer,selenium nanoparticles,cellular uptake,copper ions,fluorescence quenching,amino-functionalized graphene quantum dots
更新于2025-09-11 14:15:04
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Controlled synthesis of nanocrystalline Nb:SrTiO <sub/>3</sub> electron transport layers for robust interfaces and stable high photovoltaic energy conversion efficiency in perovskite halide solar cells
摘要： Perovskite halides are of great attraction as efficient light absorption materials for solid-state solar cells, but the stability and photovoltaic energy conversion efficiency of perovskite solar cells (PSCs) are still limited by the interface structures and defects between their light-absorbing perovskite halides and electron transport layers (ETLs). Here, we report the ultraviolet (UV) light-induced degradation mechanism at the interfaces between perovskite halide and conventional TiO2 ETL materials, and provide a solution to overcome this drawback. UV-induced degradation is shown to be attributed to the formation of oxygen vacancies formed at the perovskite halide-ETL interface under UV light illumination, where the oxygen atoms released at the interface accelerate the decomposition of perovskite halide by inducing chemical reactions. Meanwhile, nanocrystalline SrTiO3 (STO) ETLs are revealed to be tunable in enabling high performance in PSCs under UV light illumination. Indeed, tuning the electronic structure of STO ETLs by Nb doping, in combination with the controllable removal of SrO phases segregated on the Nb-doped STO ETL surfaces, is exhibited to enable robust interface stability and stable high photovoltaic energy conversion efficiency for PSCs. Furthermore, we demonstrate that STO-based PSCs have no hysteresis due to low defect concentrations at the perovskite halide-STO ETL interfaces.
关键词： oxygen vacancy formation,electron transfer layer,perovskite oxides,photo stability,Perovskite solar cells
更新于2025-09-11 14:15:04
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Stereospecific [2+2]-cross-photocycloaddition in a supramolecular donor–acceptor complex
摘要： A bis(propylammonium) derivative of (E)-4-(4-mercaptostyryl)pyridine, which was synthesized for the first time, forms a highly stable bimolecular complex with a bis(18-crown-6 ether) derivative of (E)-stilbene in solution owing to ditopic coordination via hydrogen bonds. The complex formation results in much faster deactivation of the excited states of both compounds, which is explained by photoinduced electron transfer from the stilbene derivative to the styrylpyridinium dye. Despite this, the complexed olefins undergo [2+2]-cross-photocycloaddition upon selective excitation of the dye to afford solely the syn-cycloadduct. The retro-photocycloaddition occurs readily upon UV irradiation of the cycloadduct and leads to the initial bimolecular complex.
关键词： Photoinduced electron transfer,Donor–acceptor systems,Cross-photocycloaddition,Self-assembly
更新于2025-09-10 09:29:36
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Gold Nanoclusters Enhanced Photocatalytic Property of Bismuth Oxychloride
摘要： This paper have synthesized bismuth oxychloride (BiOCl) nano-plate (BNS) by hydrothermal method and fabricated BiOCl-gold nanoclusters (Au NCs) heterostucture nanomaterials (BANC) through electrostatic interaction. X-ray diffraction, transmission electron microscope and X-ray photoelectron spectroscopy characterizations indicate Au NCs successfully modified on BNS. The small energy gap makes Au NCs suitable for absorbing sunlight, while staggered energy bands between Au NCs and BiOCl could effectively separate electrons and holes, resulting in enhanced photocatlytic performance. Actually, under simulated sunlight irradiation, BANC could completely degrade rhodamine B within 30 minutes. the photostability test showed that the structure of BNAC did not changed after irradiation.
关键词： Electron transfer,Gold nanoclusters,Bismuth Oxychloride,Photocatalysis,Dye Degradation
更新于2025-09-10 09:29:36