Engineering Active Ni Sites in Ternary Layered Double Hydroxide Nanosheets for a Highly Selective Photoreduction of CO<sub>2</sub> to CH<sub>4</sub> under Irradiation above 500 nm
Xiaojie Hao, Ling Tan, Yanqi Xu, Zelin Wang, Xian Wang, Sha Bai, Chenjun Ning, Jingwen Zhao, Yufei Zhao, Yu‐Fei Song
Abstract
Reduction of photocatalytic CO2 into renewable hydrocarbon solar fuels is considered to be a promising strategy that can simultaneously address global energy needs as well as environmental concerns. To date, making use of a higher wavelength for photocatalytic conversion of CO2 to CH4 continues to be highly challenging. In this work, we report a highly selective reduction of CO2 into CH4 and CO by introducing Ni species into CoFe-layered double hydroxide (LDH) as the visible light photocatalyst in conjunction with a Ru complex sensitizer. A more interesting finding is that the selectivity of CH4 was raised to 78.9% as compared to 0% of CoFe-LDH, while the H2 evolution was suppressed to 1.7% as compared to 30.5% of CoFe-LDH under light irradiation at λ > 500 nm. The involvement of Ni2+ ions in the CoFe-LDH layers has shown to promote the photoinduced electron–hole pair separation and thereby facilitate the photocatalytic efficiency. This work provides a new strategy for exploring the Ni-based earth-abundant photocatalysts for CO2 photoreduction.