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Hydrogenation of CO 2 to methanol is an achievable way for "methanol economy" and "liquid sunshine" visions. Owing to highly tunable properties containing different morphologies, exposed crystal facets and oxygen vacancies, In 2 O 3 has become a promising material for CO 2 hydrogenation. Here we successfully introduced highly dispersed Pt2+ species into three different morphologies In 2 O 3 supports by controllable precipitation method. The dominant exposed crystal facets of In 2 O 3 supports during the research are discovered to greatly affect the dispersion of active Pt2+ species and the number of oxygen vacancies, as analyzed by diverse characterization techniques, and closely correlated with the catalytic performance. Compared with Pt/In 2 O 3 whcih mainly exposing (222) or (104) facet, Pt/In 2 O 3 which primarily exposed (211) facet obtained higher catalytic activity, including a CO 2 conversion of 11.7% and methanol selectivity of 74.8% with a space time yield of methanol of 0.63 g MeOH h−1gcat−1 at 300 °C, 5 MPa, and 21,000 cm3 h−1g−1. The highly enhanced activity of 1.5Pt/C-In 2 O 3 -S catalyst was ascribed to its more abundant oxygen vacancies and well-dispersed Pt2+ species, which derived from the interaction between Pt2+ and the underlying In 2 O 3 (211) facet. The special interface structure enabled the activation of CO 2 and hydrogenation of key intermediates effectively. Exposing the highly active crystal face of the In 2 O 3 supports is proved to be an effective strategy to enhance catalytic performance of Pt/In 2 O 3 catalyst for methanol synthesis. The influence of the crystal facets on the 1.5Pt/In 2 O 3 catalyst was explored. Highly dispersed Pt2+ species were successfully introduced into three In 2 O 3 supports that exposed different dominant crystal facets by precipitation method. The highly enhanced activity of the 1.5Pt/C-In 2 O 3 -S catalyst was ascribed to its more abundant oxygen vacancies and well-dispersed Pt2+ species originated from the interface structure of Pt-O-In and the reinforced interaction of Pt2+ with the underlying In 2 O 3 (211) facet, which enabled both CO 2 activation and hydrogenation of key intermediates by effective H 2 dissociation. The synergistic interaction between highly dispersed Pt2+ species and In 2 O 3 crystal facet boosts the rate of methanol formation. Besides, in situ DRIFTS spectra further indicate CH 3 O* and HCOO* species are the key intermediates in the formate route. [Display omitted] • In 2 O 3 with dominant (211) facet shows the highest number of oxygen vacancies and the best Pt dispersion. • 1.5Pt/C-In 2 O 3 -S presents 11.7% CO 2 conversion and 74.8% CH 3 OH selectivity at 300 ℃. • Substitution of In3+ ions by Pt2+ ions generates the special active interface structure of Pt-O-In. • The synergy between highly dispersed Pt2+ and In 2 O 3 boost the rate of methanol formation. • CH 3 O* and HCOO* species are the key intermediates in the formate route. [ABSTRACT FROM AUTHOR]

In a global context where sustainable growth is imperative, understanding carbon emissions in significant regions is essential. Henan Province, being a vital region in China for population, agriculture, industry, and energy consumption, plays a crucial role in this understanding. This study, rooted in the need to identify strategies that not only meet China's broader carbon neutrality objectives but also offer insights regarding global sustainability models, utilizes the STIRPAT model combined with scenario analysis. The aim was to forecast carbon emission trajectories from 2020 to 2060 across the key industries—electricity, steel, cement, transportation, coal, and chemical—that are responsible for over 80% of the total emissions in Henan. The findings suggest a varied carbon peak timeline: the steel and cement industries might achieve their peak before 2025, and the transportation, coal, and chemical sectors might achieve theirs around 2030, whereas that of the power industry could be delayed until 2033. Significantly, by 2060—a landmark year for Chinese carbon neutrality ambitions—only the electricity sector in Henan shows potential for zero emissions under an extreme scenario. This study's results underscore the importance of region-specific strategies for achieving global carbon neutrality and offer a blueprint for other populous, industrialized regions worldwide. [ABSTRACT FROM AUTHOR]

Carbon capture, utilization, and storage (CCUS) technology is considered an effective way to reduce greenhouse gases, such as carbon dioxide (CO2), which is significant for achieving carbon neutrality. Based on Derwent patent data, this paper explored the technology topics in CCUS patents by using the latent Dirichlet allocation (LDA) topic model to analyze technology's hot topics and content evolution. Furthermore, the logistic model was used to fit the patent volume of the key CCUS technologies and predict the maturity and development trends of the key CCUS technologies to provide a reference for the future development of CCUS technology. We found that CCUS technology patents are gradually transforming to the application level, with increases in emerging fields, such as computer science. The main R&D institutes in the United States, Europe, Japan, Korea, and other countries are enterprises, while in China they are universities and research institutes. Hydride production, biological carbon sequestration, dynamic monitoring, geological utilization, geological storage, and CO2 mineralization are the six key technologies of CCUS. In addition, technologies such as hydride production, biological carbon sequestration, and dynamic monitoring have good development prospects, such as CCUS being coupled with hydrogen production to regenerate synthetic methane and CCUS being coupled with biomass to build a dynamic monitoring and safety system. [ABSTRACT FROM AUTHOR]

[Display omitted] • The crystalline phases of ZrO 2 greatly influence the catalytic performance over Pd/In 2 O 3 catalysts. • Pd/In 2 O 3 /Mix-ZrO 2 catalyst with mixed ZrO 2 phases exhibits a high STY of methanol. • The large size of Pd nanoparticles favors H 2 dissociation and CO 2 /intermediates hydrogenation. • The number of medium basic sites and oxygen vacancies are vital for superior performance. The crystalline phases of support have great influence on their surface and structure properties. Therefore, adjusting the crystalline structure of heterogeneous catalysts imposes a significant impact on the catalytic performance. Herein, a suite of Pd/In 2 O 3 /ZrO 2 catalysts with different crystalline phases of ZrO 2 were prepared and evaluated for CO 2 hydrogenation to CH 3 OH using the same amount of metal loading. The activity data showed the distinct superior reactivity of Pd/In 2 O 3 /ZrO 2 catalyst used mixed monoclinic and tetragonal phases ZrO 2 (Mix-ZrO 2) as support as compared to respective single phase of monoclinic ZrO 2 (m-ZrO 2) and tetragonal ZrO 2 (t-ZrO 2). The catalysts are extensively characterized through BET, XRD, HRTEM, UV–vis, H 2 -TPR, CO 2 /H 2 -TPD and XPS. Combining the characterization results and activity data, the superior activity of Pd/In 2 O 3 /Mix-ZrO 2 catalyst can be correlated with large particle size of Pd nanoparticles, the concentration of oxygen vacancies, and the abundant medium basic sites, which were essential for activation of H 2 and inert CO 2 and enhancement of catalytic performance. The best-performing Pd/In 2 O 3 /Mix-ZrO 2 catalyst exhibited a remarkable reactivity with space time yield (STY) of 0.54 g methanol ·h−1·g cat −1 at 573 K and 5 MPa, and stability without noticeable deactivation after 100 h of time on stream, demonstrating its potential as catalyst used in CH 3 OH synthesis from CO 2 hydrogenation. [ABSTRACT FROM AUTHOR]

Advances in design concept of oxide-zeolite (OX-ZEO) bifunctional tandem catalysts have demonstrated its potential for highly enhanced selectivity and yield in CO 2 conversion by assigning CO 2 activation and C-C coupling to specific oxide and zeolite, respectively. However, the crystalline structural effects of oxides have not been thoroughly investigated. Here, ZnO/ZrO 2 with different ZrO 2 crystalline phases modulated by Li doping has been used as an oxide catalyst to combine with SAPO-34 as a bifunctional composite catalyst for CO 2 hydrogenation to light olefins. With the transformation of the support ZrO 2 crystalline phase from tetragonal phase to mixed crystalline phase in the catalyst, the CO 2 conversion and yield of target product light olefins were significantly improved. The best-performing ZnO/5Li-ZrO 2 catalyst exhibited a CO 2 conversion of 28.56%, light olefins selectivity of 82.00% with a yield of 8.77% along with good stability under the reaction conditions of 380 °C, 3 MPa, and 6000 mL/g/h. The characterization results by XRD, Raman, HRTEM, XPS and CO 2 -TPD confirmed that the highly enhanced catalytic performance was attributed to the strong interaction between the mixed crystal phase 5Li-ZrO 2 and ZnO, which generated a large number of oxygen vacancies for CO 2 activation. The results indicate that controlling the crystal phase of the oxide support is of prime importance in designing more active and selective oxide-zeolite bifunctional catalysts for high-efficiency CO 2 to light olefins conversion. [Display omitted] • The mixed ZrO 2 crystal phases boost the catalytic hydrogenation of the bifunctional tandem catalysts. • The ZnO/5Li-ZrO 2 -SAPO-34 tandem catalysts exhibits superior activity due to strong interaction between ZnO and 5Li-ZrO 2. • The ZnO/5Li-ZrO 2 catalysts possess a large number of oxygen vacancies and moderately basic sites. • The ZnO/5Li-ZrO 2 -SAPO-34 tandem catalysts exhibits high CO 2 conversion (28.56%) and light olefins yield (8.77%) at 380 °C. [ABSTRACT FROM AUTHOR]