Diatomite-Induced coordination transformation enables highly dispersed Bi-MOF nanowhiskers for efficient photocatalytic CO2 reduction

Diatomite-induced amino coordination transformation Bi-MOF composite was prepared. • Surface silanol groups modulate Bi 3+ coordination, inducing amino ligand transformation. • The coordination transformation forms highly dispersed NH 2 -Bi-MOF nanowhiskers. • The composite shows enhanced photocatalysis, cycling stability and lower costs. Developing photocatalysts featuring outstanding catalytic activity and economic viability contributes greatly to artificial carbon cycling and addressing energy and environmental challenges. In this study, we adopted a strategy combining amino ligand modification with diatomite support to successfully synthesize amino-modified NH 2 -Bi-MOF/diatomite composites. These materials utilize the silanol groups on the diatomite surface to modulate the coordination environment of the Bi 3+ metal centers, inducing the conversion of amino ligands and promoting the formation of Bi-N bonds, thereby transforming the morphology of the NH 2 -Bi-MOF from an agglomerated state to highly dispersed nanowhiskers. The characterization results indicate that the highly dispersed structure endows the material with outstanding chemical stability, light-harvesting capability, CO 2 adsorption capacity, and carrier separation efficiency. Meanwhile, the optimal sample, NH 2 -Bi-MOF/diatomite-0.2, achieves a CO production rate of 10.440 μmol·g −1 ·h −1 , representing increases of 78% and 45% compared to Bi-MOF and NH 2 -Bi-MOF, respectively. Notably, no apparent decline in catalytic performance was observed after four cycles. Furthermore, the introduction of diatomite substantially reduces catalyst preparation costs. This study also systematically elucidates the conversion mechanism of amino ligands and the interfacial synergy between diatomite and NH 2 -Bi-MOF, clarifying the photocatalytic CO 2 reduction pathways and core mechanisms of the composite material. The findings provide new insights for the development and industrial application of highly efficient and economical photocatalysts. Download: Download high-res image (191KB) Download: Download full-size image