Photo-induced self-catalysis of nano-Bi 2 MoO 6 for solar energy harvesting and charge storage

• Published in: RSC advances 2020-10, Vol.10 (62), p.38033-38037
• Main Authors: Si, Jiangju, Guo, Changmeng, Liu, Haojie, Li, Weiwei, Guo, Xiaowei, Bai, Peidong, Liu, Yanghong, Chen, Gairong, Sun, Ningbo
• Format: Article
• Language: English
• ISSN: 2046-2069; 2046-2069
• DOI: 10.1039/D0RA07020C

Efficient, sustainable, and integrated energy systems require the development of novel multifunctional materials to simultaneously achieve solar energy harvesting and charge storage. Bi-based oxysalt aurivillius phase materials are potential candidates due to their typical photovoltaic effect and their pseudo-capacitance charge storage behavior. Herein, we synthesized nano-Bi MoO as a material for both solar energy harvesting and charge storage due to its suitable band gap for absorption of visible light and its well-defined faradaic redox reaction from Bi metal to Bi . The irradiation of visible light significantly affected the electrochemical processes and the dynamics of the Bi MoO electrode. The photo-induced self-catalytic redox mechanism was carefully explored by adding sacrificial agents in photocatalysis reaction. In accordance with the rule of energy matching, the photo-generated holes oxidized the Bi metal to Bi , and the corresponding peak current increased by 79.5% at a scanning rate of 50 mV s . More importantly, the peak current retention rate remained higher than 92.5% during the entire 200 cycles. The photo-generated electrons facilitated a decrease of 184 mV in the overpotential of the reduction process. Furthermore, the irradiation of visible light also accelerated the ionic diffusion of the electrolyte. These investigations provide a unique perspective for the design and development of new multifunctional materials to synergistically realize solar energy harvesting and charge storage.