Understanding the structure of Cu-doped MgAl2O4 for CO2 hydrogenation catalyst precursor using experimental and computational approaches

The combination of experiments and simulations revealed the structural and electronic origins of Cu-doped MgAl2O4 spinel-type oxides, which we developed as the catalyst precursor for CO2-to-methanol hydrogenation. When the doping was high, elongated OeCu octahedrally coordinated [CuO6](el) was confirmed in the spinel structure. As the amount decreased, [CuO6] el was deformed to short O-Cu octahedrally coordinated [CuO6](s). Simultaneously, O atoms surrounding Cu atoms became more negatively charged, and Cu nanoparticle with a size <10 nm was formed by H-2 reduction. The Cu nanoparticles derived from [CuO6](s) was highly selective to CO2-to-methanol hydrogenation. (C) 2022 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Automated summary

The combination of experiments and simulations revealed the structural and electronic origins of Cu-doped MgAl2O4 spinel-type oxides, which were developed as the catalyst precursor for CO2-to-methanol hydrogenation. The presence of elongated OeCu octahedrally coordinated [CuO6](el) in the spinel structure was confirmed at high doping levels. As the amount of doping decreased, [CuO6] el deformed to short O-Cu octahedrally coordinated [CuO6](s). Simultaneously, the surrounding O atoms became more negatively charged, and Cu nanoparticles with a size smaller than 10 nm were formed through H-2 reduction. The Cu nanoparticles derived from [CuO6](s) exhibited high selectivity for CO2-to-methanol hydrogenation.