In Situ Construction of MIL-100@NiMn-LDH Hierarchical Architectures for Highly Selective Photoreduction of CO 2 to CH 4

• Published in: ACS applied materials & interfaces 2022-04, Vol.14 (14), p.16369-16378
• Main Authors: Sun, Danzhong, Li, Jiao, Shen, Tianyang, An, Sai, Qi, Bo, Song, Yu-Fei
• Format: Article
• Language: English
• ISSN: 1944-8244; 1944-8252
• DOI: 10.1021/acsami.2c02888

Layered double hydroxides (LDHs) are considered a promising catalyst for photocatalytic CO reduction due to their broad photoresponse, facile channels for electron transfer, and the presence of abundant defects. Herein, we reported for the first time the fabrication of a novel photocatalyst MIL-100@NiMn-LDH with a hierarchical architecture by selecting MIL-100 (Mn) as a template to provide Mn for the growth of ultrathin NiMn-LDH nanosheets. Moreover, the growth strategy exhibited excellent universality toward constructing MIL-100@LDH hierarchical architectures. When applied in the photocatalytic CO reduction reaction, the as-prepared MIL-100@NiMn-LDH exhibited excellent CH selectivity of 88.8% (2.84 μmol h ), while the selectivity of H was reduced to 1.8% under visible light irradiation (λ > 500 nm). Such excellent catalytic performance can be attributed to the fact that (a) the MIL-100@NiMn-LDH hierarchical architectures with exposed catalytic active sites helped to enhance the CO adsorption and activation and (b) the presence of rich oxygen vacancies and coordinately unsaturated metal sites in MIL-100@NiMn-LDH that optimized the band gap and accelerated the separation/transport of photoinduced charges.