Recent Advances of Indium Oxide-Based Catalysts for CO2 Hydrogenation to Methanol: Experimental and Theoretical

Abstract

Methanol synthesis from the hydrogenation of carbon dioxide (CO2) with green H2 has been proven as a promising method for CO2 utilization. Among the various catalysts, indium oxide (In2O3)-based catalysts received tremendous research interest due to the excellent methanol selectivity with appreciable CO2 conversion. Herein, the recent experimental and theoretical studies on In2O3-based catalysts for thermochemical CO2 hydrogenation to methanol were systematically reviewed. It can be found that a variety of steps, such as the synthesis method and pretreatment conditions, were taken to promote the formation of oxygen vacancies on the In2O3 surface, which can inhibit side reactions to ensure the highly selective conversion of CO2 into methanol. The catalytic mechanism involving the formate pathway or carboxyl pathway over In2O3 was comprehensively explored by kinetic studies, in situ and ex situ characterizations, and density functional theory calculations, mostly demonstrating that the formate pathway was extremely significant for methanol production. Additionally, based on the cognition of the In2O3 active site and the reaction path of CO2 hydrogenation over In2O3, strategies were adopted to improve the catalytic performance, including (i) metal doping to enhance the adsorption and dissociation of hydrogen, improve the ability of hydrogen spillover, and form a special metal-In2O3 interface, and (ii) hybrid with other metal oxides to improve the dispersion of In2O3, enhance CO2 adsorption capacity, and stabilize the key intermediates. Lastly, some suggestions in future research were proposed to enhance the catalytic activity of In2O3-based catalysts for methanol production. The present review is helpful for researchers to have an explicit version of the research status of In2O3-based catalysts for CO2 hydrogenation to methanol and the design direction of next-generation catalysts.

Development of In–Cu binary oxide catalysts for hydrogenating CO2via thermocatalytic and electrocatalytic routes

“…In situ and operando characterization have demonstrated that In 2 O 3 is the active phase for the methanol formation, whereas In 0 led to the catalyst deactivation in the CO 2 hydrogenation at high temperatures and pressures. 62 Conversely, our results evidenced that the co-presence of different phases and oxidation states (In 0 , In 2 O 3 , In(OH) 3 ) actively participate in the electrochemical CO 2 reduction reaction to formate and more reduced products, demonstrating that employing fundamental similarities from the viewpoint of surface science and electrical potentials instead of elevated temperatures show a synergistic interaction in hydrogenating CO 2 . 32,50 Formate or formic acid is a desirable liquid fuel candidate and profitable product because of its high energy density (7.6 MJ L −1 ) and value as a raw material for obtaining several organic compounds.…”

“…Regarding electrocatalysis, in the literature, those post-transition elements are classified to possess a weak *H bond, suppressing hydrogen evolution and favouring the thermodynamically preferred CO 2 reduction. 62…”

Integration of genome-scale metabolic model with biorefinery process model reveals market-competitive carbon-negative sustainable aviation fuel utilizing microbial cell mass lipids and biogenic CO2

“…The CO2-to-methanol conversion process has been demonstrated at bench scale, and most recent works are focused on the selection of catalysts (Heracleous et al 2023;Cai et al 2023) that can enhance CO2 conversion and methanol selectivity. Furthermore, researchers are conducting conversion of CO2 in the liquid phase (Kothandaraman et al 2022) instead of gas-phase CO2 conversion into methanol.…”

Antiover-Reduction of Ni/In2O3 Nanocatalysts by Atomic Layer Deposition of Al2O3 Films for Durable CO2 Hydrogenation to Methanol

“…To date, various metallic catalysts have been developed to boost CO 2 hydrogenation into methanol, including Cu/ZnO, Pd/ZnO, ZnZrO x solid solution, In 2 O 3 , and others. It is widely accepted that In 2 O 3 is a promising catalyst for CO 2 hydrogenation to methanol due to the periodic generation and annihilation mechanism of surface oxygen vacancy for activating CO 2 .…”