Production of methanol from CO 2 hydrogenation is a highly attractive method toward recycling greenhouse gases to form clean, high-value commodity chemicals and fuels, with the aim of resolving both environmental issues and energy shortages. This review provides an overview of Cu-based nanocatalyst development for CO 2 hydrogenation to methanol that has been achieved recently in terms of support design, promoter addition, and structural improvements, as this line of research has become very popular. In addition, the reaction mechanisms from both experimental work and density functional theory calculations are summarized to showcase key factors influencing the reaction. The overall methanol yield can be tailored by metal active sites and metal− support interaction, as well as the function of promoters. The technical and application challenges of methanol production from CO 2 hydrogenation are also summarized with proposed future research directions.

A set of Ni−ZnO/MCM-41 catalysts with different proportional Ni and ZnO loadings (up to 10 wt % in total) were synthesized for the carbon dioxide (CO 2 ) hydrogenation reaction. Ni nanoparticles and ZnO promoter were both loaded onto a MCM-41 support via the impregnation method. The catalysts were comprehensively characterized by Brunauer−Emmett−Teller, Xray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy, and hydrogen temperature-programmed reduction measurements. Catalyst properties, including the porosity, Ni metal particle size, and Ni particle location, were all found to be influenced by the presence of the ZnO promoter. ZnO was suspected to improve Ni nanoparticle insertion into the MCM-41 mesoporous channels to form Ni−ZnO interfaces. Both CO and CH 4 were produced during the CO 2 hydrogenation reaction under the molar ratio of CO 2 /H 2 at 1:3 at 350 °C. The CO 2 conversion rate and CO selectivity were found to increase as the reaction temperature increased from 350 to 700 °C. Among all studied materials, the catalyst containing 9 wt % Ni and 1 wt % Zn (denoted as sample E throughout the report) revealed the highest CO 2 conversion and selectivity toward CO (∼60% CO 2 conversion and 98.5% CO selectivity at 600 °C), while the catalyst containing 1 wt % Ni and 9 wt % Zn (denoted as sample A throughout the report) revealed the lowest activity (∼2.5% CO 2 conversion and 95% CO selectivity at 600 °C). This study illustrated that cooperative catalysis can be applied to tune the CO 2 hydrogenation reaction toward the reverse water−gas shift reaction for valueadded CO production. When both Ni and ZnO are coupled in MCM-41, a hybrid system was designed and synthesized, in which Ni functions for H 2 dissociation and ZnO functions for CO 2 adsorption and accumulation.

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