Regulated Photocatalytic CO<sub>2</sub>-to-CH<sub>3</sub>OH Pathway by Synergetic Dual Active Sites of Interlayer
Jiacong Wu, Fei Huang, Qinyuan Hu, Dongpo He, Wenxiu Liu, Xiaodong Li, Wensheng Yan, Jun Hu, Junfa Zhu, Shan Zhu, Qingxia Chen, Xingchen Jiao, Yi Xie
Abstract
Herein, composites of nanosheets with van der Waals contacts are employed to disclose how the interlayer-microenvironment affects the product selectivity of carbon dioxide (CO 2 ) photoreduction. The concept of composites of nanosheets with dual active sites is introduced to manipulate the bonding configuration and promote the thermodynamic formation of methanol (CH 3 OH). As a prototype, the CoNi 2 S 4 –In 2 O 3 composites of nanosheets are prepared, in which high-resolution transmission electron microscopy imaging, X-ray photoelectron spectroscopy spectra, and zeta potential tests confirm the presence of van der Waals contacts rather than chemical bonding between the In 2 O 3 nanosheets and the CoNi 2 S 4 nanosheets within the composite. The fabricated CoNi 2 S 4 –In 2 O 3 composites of nanosheets exhibit the detection of the key intermediate *CH 3 O during CO 2 photoreduction through in situ Fourier transform infrared spectra, while the In 2 O 3 nanosheets and CoNi 2 S 4 nanosheets alone do not show this capability, further verified by the density functional theory calculations. Accordingly, the CoNi 2 S 4 –In 2 O 3 composites of nanosheets show the ability to produce CH 3 OH, whereas the CoNi 2 S 4 and In 2 O 3 nanosheets solely generate carbon monoxide products from CO 2 photoreduction.