The utilization of fossil fuels has enabled an unprecedented era of prosperity and advancement of well-being for human society. However, the associated increase in anthropogenic carbon dioxide (CO2) emissions can negatively affect global temperatures and ocean acidity. Moreover, fossil fuels are a limited resource and their depletion will ultimately force one to seek alternative carbon sources to maintain a sustainable economy. Converting CO2 into value-added chemicals and fuels, using renewable energy, is one of the promising approaches in this regard. Major advances in energy-efficient CO2 conversion can potentially alleviate CO2 emissions, reduce the dependence on nonrenewable resources, and minimize the environmental impacts from the portions of fossil fuels displaced. Methanol (CH3OH) is an important chemical feedstock and can be used as a fuel for internal combustion engines and fuel cells, as well as a platform molecule for the production of chemicals and fuels. As one of the promising approaches, thermocatalytic CO2 hydrogenation to CH3OH via heterogeneous catalysis has attracted great attention in the past decades. Major progress has been made in the development of various catalysts including metals, metal oxides, and intermetallic compounds. In addition, efforts are also put forth to define catalyst structures in nanoscale by taking advantage of nanostructured materials, which enables the tuning of the catalyst composition and modulation of surface structures and potentially endows more promising catalytic performance in comparison to the bulk materials prepared by traditional methods. Despite these achievements, significant challenges still exist in developing robust catalysts with good catalytic performance and long-term stability. In this review, we will provide a comprehensive overview of the recent advances in this area, especially focusing on structure-activity relationship, as well as the importance of combining catalytic measurements, in situ characterization, and theoretical studies in understanding reaction mechanisms and identifying key descriptors for designing improved catalysts.

Recent Advances in Carbon Dioxide Hydrogenation to Methanol via Heterogeneous Catalysis.

Utilization of CO2 as feedstock to produce fine chemicals and renewable fuels is a highly promising field, which presents unique challenges in its implementation at scale. Heterogeneous catalysis w...

Advances in the Design of Heterogeneous Catalysts and Thermocatalytic Processes for CO2 Utilization

Carbon dioxide (CO2) hydrogenation to methanol with H2 produced with renewable energy represents a promising path for the effective utilization of a major anthropogenic greenhouse gas, in which cat...

CO2Hydrogenation to Methanol over In2O3-Based Catalysts: From Mechanism to Catalyst Development

Carbon dioxide (CO2) hydrogenation to liquid fuels including gasoline, jet fuel, diesel, methanol, ethanol, and other higher alcohols via heterogeneous catalysis, using renewable energy, not only effectively alleviates environmental problems caused by massive CO2 emissions, but also reduces our excessive dependence on fossil fuels. In this Outlook, we review the latest development in the design of novel and very promising heterogeneous catalysts for direct CO2 hydrogenation to methanol, liquid hydrocarbons, and higher alcohols. Compared with methanol production, the synthesis of products with two or more carbons (C2+) faces greater challenges. Highly efficient synthesis of C2+ products from CO2 hydrogenation can be achieved by a reaction coupling strategy that first converts CO2 to carbon monoxide or methanol and then conducts a C-C coupling reaction over a bifunctional/multifunctional catalyst. Apart from the catalytic performance, unique catalyst design ideas, and structure-performance relationship, we also discuss current challenges in catalyst development and perspectives for industrial applications.

Novel Heterogeneous Catalysts for CO2 Hydrogenation to Liquid Fuels.

https://pubs.rsc.org/en/content/articlepdf/2021/cy/d0cy01913e

Recent advances in hydrogenation of CO2 into hydrocarbons via methanol intermediate over heterogeneous catalysts

The catalytic hydrogenation of CO2 to methanol has been regarded as the one of the most economical and effective ways to reduce CO2 emissions. It can also provide a feasible idea for solving the energy crisis. In this paper, a series of Pd/In2O3/SBA-15 catalysts were prepared by the citric acid method. The DFT simulation and catalyst characterization including the N2 adsorption, XRD, H2-TPR, TEM, XPS and CO2-TPD were applied. The results showed that the as-prepared Pd/In2O3/SBA-15 catalysts exhibited superior catalytic activity with 83.9% methanol selectivity and 12.6% CO2 conversion, corresponding to a STY of 1.1 × 10-2 mol·h-1·gcat-1 under reaction conditions of 260 °C, 5 Mpa and 15,000 cm3 h-1·gcat-1. It is suggested that the synergetic effect of H2 dissociation on Pd species and CO2 activation on In2O3 promoted the high efficiency conversion of CO2 to methanol.

Efficient hydrogenation of CO2 to methanol over Pd/In2O3/SBA-15 catalysts

In this work, a hollow double-shelled architecture, based on n-type ZnIn2S4 nanosheet-coated p-type CuS hollow octahedra (CuS@ZnIn2S4 HDSOs), is designed and fabricated as a p-n heterojunction photocatalyst for selective CO2 photoreduction into CH4. The resulting hybrids provide rich active sites and effective charge migration/separation to drive CO2 photoreduction, and meanwhile, CO detachment is delayed to increase the possibility of eight-electron reactions for CH4 production. As expected, the optimized CuS@ZnIn2S4 HDSOs manifest a CH4 yield of 28.0 μmol g-1 h-1 and a boosted CH4 selectivity up to 94.5%. The decorated C60 both possesses high electron affinity and improves catalyst stability and CO2 adsorption ability. Thus, the C60-decorated CuS@ZnIn2S4 HDSOs exhibit the highest CH4 evolution rate of 43.6 μmol g-1 h-1 and 96.5% selectivity. This work provides a rational strategy for designing and fabricating efficient heteroarchitectures for CO2 photoreduction.

Hierarchical CuS@ZnIn2S4 Hollow Double-Shelled p-n Heterojunction Octahedra Decorated with Fullerene C60 for Remarkable Selectivity and Activity of CO2 Photoreduction into CH4.

Efficient charge transfer and CO2 photoreduction of hierarchical CeO2@SnS2 heterostructured hollow spheres with spatially separated active sites

Highly dispersed palladium nanoparticles (NPs) supported on UiO-66 as catalyst for CO2 methanation were prepared by supercritical fluid deposition (SFD). As a result, the most suitable Pd precursor salt and co-solvent are Na2PdCl4 and ethanol/DMF, respectively. The best SFD process condition to deposit the Pd precursor on UiO-66 is 40 °C, 10 MPa and 2 h. Under the above condition, 4% Pd/UiO-66 exhibits the highest activity with 53% of CO2 conversion and 95% of CH4 selectivity while the turnover frequency (TOF) value is 3669.4 h−1. The catalysts were characterized by XRD, BET, TEM, XPS, TGA, CO-DRIFTS and ICP-OES to investigate the structure–activity relationship. The 4% Pd/UiO-66 with the average size of 2.2 nm of Pd prepared in assistance of supercritical fluid behaved the similar activity as the 6%Pd/UiO-66 with average size of 9.7 nm of Pd prepared by sol–gel method. It is showed prospect of technique for reducing noble metal loading resulting from high dispersion effect.

Highly-dispersed Pd nanoparticles on UiO-66 in assistance of supercritical fluid and its catalytic performance of CO2 methanation

Efficient charge transfer in cadmium sulfide quantum dot-decorated hierarchical zinc sulfide-coated tin disulfide cages for carbon dioxide photoreduction.

Jing Lin

Papers

Efficient hydrogenation of CO2 to methanol over Pd/In2O3/SBA-15 catalysts

Hierarchical CuS@ZnIn2S4 Hollow Double-Shelled p-n Heterojunction Octahedra Decorated with Fullerene C60 for Remarkable Selectivity and Activity of CO2 Photoreduction into CH4.

Efficient charge transfer and CO2 photoreduction of hierarchical CeO2@SnS2 heterostructured hollow spheres with spatially separated active sites

Highly-dispersed Pd nanoparticles on UiO-66 in assistance of supercritical fluid and its catalytic performance of CO2 methanation

Efficient charge transfer in cadmium sulfide quantum dot-decorated hierarchical zinc sulfide-coated tin disulfide cages for carbon dioxide photoreduction.