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In recent years, with global climate change, the utilization of carbon dioxide as a resource has become an important goal of human society to achieve carbon peaking and carbon neutrality. Among them, the catalytic conversion of carbon dioxide to generate renewable fuels has received great attention. As one of these methods, photocatalysis has its unique properties and mechanism, which can only rely on sunlight without inputting other energy. It is an emerging discipline with great development prospects. The core of photocatalysis lies in the development of photocatalysts with high activity, high selectivity, low cost, and high durability. This review first introduces the background and mechanism of photocatalysis, then introduces various types of photocatalysts based on different substrates, and analyzes the methods and mechanisms to improve the activity and selectivity of photocatalysts. Finally, combining the plasmon effect with photocatalysis, the review analyzes the promoting effect of the plasmon effect on the photocatalytic carbon dioxide synthesis of renewable fuels, which provides a new idea for it. [ABSTRACT FROM AUTHOR]

This paper mainly studied the influence of the Si/Al ratio on the performance of the Cu/SSZ-13 catalyst synthesized by the ion exchange method. NH3-SCR experimental results show that the catalyst SAR10 has the best catalytic performance, and it can maintain a 100% conversion rate in the range of 250 °C to 600 °C. Although SAR6 samples with low Si/Al ratios have abundant active centers, their low temperature activity is poor due to their poor crystallinity. The decrease of the number of active sites available for exchange in the SAR25 sample with too high an Si/Al ratio results in a decrease in catalytic activity throughout the temperature range. The results of the in situ DRIFTS experiment show that the order of the number of Lewis acid sites and the content of monodentate nitrate adsorption sites is the same as the order of catalytic activity. [ABSTRACT FROM AUTHOR]

The Cu/SSZ-13 catalyst with Si/Al ratio of 10 and Cu/Al ratio in the range of 0.005 to 0.5 was synthesized by ion exchange method. The effect of Cu/Al ratio on the performance, selectivity, and active center of the catalyst SCR was studied. The samples with too low Cu/Al ratio have low catalytic activity in the entire temperature range due to the small number of active sites. The samples with too high Cu/Al ratio have good performance in the low temperature range due to the large number of active sites. However, a large amount of copper that has not undergone ion exchange will generate CuO, which greatly enhances the oxidation of NH3 at high temperatures, which in turn leads to a decrease in catalytic performance at high temperatures. XRD and BET experiments show that all catalyst samples have good CHA crystal structure and microporous structure, and the pore size is mostly about 2 nm. In situ DRIFTS analysis shows that when the Cu/Al ratio is low, the proportion of Z2Cu in the active sites is higher, and the stability of the catalyst is enhanced. When the copper–aluminum ratio is high, the proportion of ZCuOH increases, and the low-temperature activity of the catalyst is higher. [ABSTRACT FROM AUTHOR]

• Low and high temperature hydrothermal stability of Cu/SAPO-34 and Cu/SSZ-13 are studied. • Both low and high temperature aging decrease catalytic property of Cu/SAPO-34. • Al-rich CuO x clusters, aggregated CuO x clusters, and AlPO 4 species are found over aged Cu/SAPO-34. • High temperature aging leads to significant performance decline of Cu/SSZ-13. • High temperature aged Cu/SSZ-13 exhibits severe lack of active sites and structural degradation. This research focused on the hydrothermal tolerance of Cu/SAPO-34 and Cu/SSZ-13 catalysts. Either low- or high-temperature aging decreases the catalytic property of Cu/SAPO-34. Cu/SAPO-34 lost some isolated copper sites, and new copper-aluminum complexes CuAl 2 O 4 and Al-rich CuO x clusters formed after low temperature aging. High temperature aging resulted in CuO x clusters and AlPO 4 species formed, which led to the loss of Cu2+ active sites and surface nitrates adsorbed sites over Cu/SAPO-34. Cu/SSZ-13 retained the catalytic performance after low temperature aging but was totally intolerant to high temperature aging. High temperature hydrothermal aging led to the loss of active sites, lack of surface nitrates adsorbed sites, and serious structural degradation over Cu/SSZ-13. [Display omitted] [ABSTRACT FROM AUTHOR]

• Using DFT to explore the adsorption of gas molecules on catalysts surface. • Investigating the characteristics of catalytic active sites and reaction mechanisms through DFT. • Explaining the catalysts poisoning process through DFT. • Illustrating the catalysts hydrothermal aging process through DFT. • Catalysts modification and design based on DFT. In recent years, molecular simulation methods, especially density functional theory (DFT), have attracted much attention and been widely used to study the SCR reaction theoretically and microscopically. This review discusses the application of DFT in SCR research from the aspects of surface adsorption, active site characteristics, reaction mechanism, poisoning mechanism, and hydrothermal aging mechanism to illustrate the status of quantum chemical computing in this field. The gas adsorption includes the adsorption of nitrogen oxides, ammonia, and their co-adsorption. The site and mechanism include the properties of different active sites, intermediate species analysis, and reaction mechanism research. The poisoning includes related research on sulfur poisoning and alkali metal poisoning. The hydrothermal aging includes research on dealumination and loss of active sites. It is demonstrated that the catalysts can be improved and rationally designed based on quantum chemistry calculations. Finally, the application of DFT in this field is evaluated, hoping to provide good suggestions for DFT calculations to further understand the more complicated reaction mechanisms and optimally design the SCR catalysts. [Display omitted] [ABSTRACT FROM AUTHOR]