Copper selenide (Cu3Se2 and Cu2−xSe) thin films: electrochemical deposition and electrocatalytic application in quantum dot-sensitized solar cells
| Autor: | Lei Wan, Yuanzhang Huang, Jun Xu, Haihong Niu, Yuan Li, Jinzhang Xu, Ru Zhou, Juntian Zhou |
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| Rok vydání: | 2018 |
| Předmět: |
Tafel equation
Materials science Annealing (metallurgy) chemistry.chemical_element 02 engineering and technology Electrolyte 010402 general chemistry 021001 nanoscience & nanotechnology Electrochemistry 01 natural sciences Copper 0104 chemical sciences Inorganic Chemistry chemistry Chemical engineering Quantum dot Electrode Thin film 0210 nano-technology |
| Zdroj: | Dalton Transactions. 47:16587-16595 |
| ISSN: | 1477-9234 1477-9226 |
| DOI: | 10.1039/c8dt03791d |
| Popis: | In this work, high crystallinity copper selenide thin films directly deposited onto conducting substrates were obtained through a potentiostatic electrodeposition approach. The as-deposited copper selenides involve annealing induced phase transformation from tetragonal Cu3Se2 to cubic Cu2-xSe. The annealing also leads to a remarkable morphology change from dendritic nanosheets to connected networks and separated particle shapes for the annealed (A-Cu2-xSe) and selenized (S-Cu2-xSe) samples, respectively. The copper selenide thin films were demonstrated to serve as efficient counter electrodes (CEs) in quantum dot-sensitized solar cells (QDSCs) for electrocatalyzing polysulfide electrolyte regeneration. The CdS/CdSe QDSCs constructed with copper selenide CEs deliver considerable power conversion efficiencies (PCEs), especially an optimal value of 3.89% for the A-Cu2-xSe CE-based device. The enhanced photovoltaic performance benefits from the connected network microstructure of A-Cu2-xSe films which afford a large number of reaction sites and efficient charge transport pathways. The Tafel polarization characterization further indicates that, in contrast to the commonly used Cu2S and Pt CEs, the non-stoichiometric Cu2-xSe CE exhibits better electrochemical catalytic activity. This work highlights the great potential of electrodeposition for fabricating promising copper selenide CEs for high performance QDSCs. |
| Databáze: | OpenAIRE |
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