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Seksaria H, Kishore A, De Sarkar A. Temperature-driven journey of dark excitons to efficient photocatalytic water splitting in β-AsP. Phys Chem Chem Phys 2024. [PMID: 38979625 DOI: 10.1039/d4cp01937g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/10/2024]
Abstract
Limited availability of photogenerated charge carriers in two-dimensional (2D) materials, due to high exciton binding energies, is a major bottleneck in achieving efficient photocatalytic water splitting (PWS). Strong excitonic effects in 2D materials demand precise attention to electron-electron correlation, electron-hole interaction and electron-phonon coupling simultaneously. In this work, we explore the temperature-dependent electronic and optical responses of an efficient photocatalyst, blue-AsP (β-AsP), by integrating electron-phonon coupling into state-of-the-art GW + BSE calculations. Interestingly, strong electron-lattice interaction at high temperature promotes photocatalytic water splitting with an increasing supply of long-lived dark excitons. This work presents an atypical observation contrary to the general assumption that only bright excitons enhance the PWS due to prominent absorption. Dark excitons, due to the low recombination rate, exhibit long-lived photogenerated electron-hole pairs with high exciton lifetime increasing with temperature up to ∼0.25 μs.
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Affiliation(s)
- Harshita Seksaria
- Institute of Nano Science and Technology, Knowledge City, Sector 81, Manauli, Mohali, Punjab 140306, India.
| | - Amal Kishore
- Institute of Nano Science and Technology, Knowledge City, Sector 81, Manauli, Mohali, Punjab 140306, India.
| | - Abir De Sarkar
- Institute of Nano Science and Technology, Knowledge City, Sector 81, Manauli, Mohali, Punjab 140306, India.
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Zhao S, Zhang C, Wang S, Lu K, Wang B, Huang J, Peng H, Li N, Liu M. Photothermally driven decoupling of gas evolution at the solid-liquid interface for boosted photocatalytic hydrogen production. NANOSCALE 2023; 16:152-162. [PMID: 38063805 DOI: 10.1039/d3nr04937j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2023]
Abstract
The slow mass transfer, especially the gas evolution process at the solid-liquid interface in photocatalytic water splitting, restricts the overall efficiency of the hydrogen evolution reaction. Here, we report a novel gas-solid photocatalytic reaction system by decoupling hydrogen generation from a traditional solid-liquid interface. The success relies on annealing commercial melamine sponge (AMS) for effective photothermal conversion that leads to rapid water evaporation. The vapor flows towards the photocatalyst covering the surface of the AMS and is split by the catalyst therein. This liquid-gas/gas-solid coupling system avoids the formation of photocatalytic bubbles at the solid-liquid interface, leading to significantly improved mass transfer and conversion. Utilizing CdS nanorods anchored by highly dispersed nickel atoms/clusters as a model photocatalyst, the highest hydrogen evolution rate from water splitting reaches 686.39 μmol h-1, which is 5.31 times that of the traditional solid-liquid-gas triphase system. The solar-to-hydrogen (STH) efficiency can be up to 2.06%. This study provides a new idea for the design and construction of efficient practical photocatalytic systems.
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Affiliation(s)
- Shidong Zhao
- International Research Center for Renewable Energy, State Key Laboratory of Multiphase Flow in Power Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, P. R. China.
| | - Chunyang Zhang
- International Research Center for Renewable Energy, State Key Laboratory of Multiphase Flow in Power Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, P. R. China.
| | - Shujian Wang
- International Research Center for Renewable Energy, State Key Laboratory of Multiphase Flow in Power Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, P. R. China.
| | - Kejian Lu
- International Research Center for Renewable Energy, State Key Laboratory of Multiphase Flow in Power Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, P. R. China.
| | - Biao Wang
- International Research Center for Renewable Energy, State Key Laboratory of Multiphase Flow in Power Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, P. R. China.
| | - Jie Huang
- International Research Center for Renewable Energy, State Key Laboratory of Multiphase Flow in Power Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, P. R. China.
| | - Hao Peng
- International Research Center for Renewable Energy, State Key Laboratory of Multiphase Flow in Power Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, P. R. China.
| | - Naixu Li
- School of Chemistry and Chemical Engineering, Southeast University, No.2 Dongnandaxue Road, Nanjing 211189, Jiangsu, P. R. China
| | - Maochang Liu
- International Research Center for Renewable Energy, State Key Laboratory of Multiphase Flow in Power Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi 710049, P. R. China.
- Suzhou Academy of Xi'an Jiaotong University, Suzhou, Jiangsu 215123, P. R. China
- Gree Altairnano New Energy Inc, Zhuhai, Guangdong 519040, P. R. China
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