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The survival and sustainable development of humanity are gravely threatened by climate change, which has recently been elevated to the status of one of the greatest threats to humanity’s survival and security on a worldwide scale. In response to global climate change, how to obtain renewable and clean fuels is an important challenge for the sustainable development of human society. In order to reach the carbon peak and attain carbon neutrality, using CO2as a resource has become a crucial aim for human civilization. Converting CO2into chemical products with higher added value, that is, CO2resource utilization technology can not only achieve CO2emission reduction but also have certain economic benefits. The technologies of CO2resource utilization primarily include photocatalytic reduction, electrocatalytic reduction, thermal catalytic reduction, and relay catalysis. This paper mainly summarizes the mechanism of CO2catalytic conversion technologies and the research status of related catalysts, and summarizes and discusses prospects for the development of the CO2catalytic reduction system (catalyst modification, product selectivity improvement, etc.). The ideas and guidance are provided for the development of efficient and stable CO2reduction catalysts and the application of CO2catalytic reduction technology in the areas of environment and energy.

Faced with the aggravation of environmental pollution and the looming energy crisis, BiVO4, as an emerging and promising photocatalyst, has drawn more and more attention of researchers. Because of its suitable band gap and special electronic structure, BiVO4shows excellent photocatalytic activity, which has the advantages of low preparation cost, excellent visible-light absorption, and suitable edge position. Herein, the research status of BiVO4-related catalysts used in photocatalysis was reviewed, including preparations using the hydrothermal method, metal–organic decomposition method, metal doping like noble metal and rare earth, and other structure designs of BiVO4. The modification mechanism of BiVO4was also further discussed and summarized. The excellent photocatalytic performance of BiVO4also enables its application to more than just PEC and CO2reduction. Finally, through the review of this paper, we hope to make a contribution to the ideas and synthesis of BiVO4photocatalysts with better comprehensive properties.

In today’s context of carbon-neutral carbon peaking and uneven distribution of global fossil energy, future-oriented artificial photosynthesis may become the key to solving the problem, and the realization of photothermal coupling catalytic one-step reduction of CO2and H2O to renewable synthetic fuels is a more critical step in the selection and design of catalysts and the study of the reaction mechanism. Among them, TiO2is widely used in the photothermal reduction of CO2because of its excellent photothermal chemical properties. However, the photothermal catalytic mechanism of TiO2is not clear at present, and there is a lack of effective modification to enhance the catalytic activity. In this study, TiO2nanoribbon materials with an anatase phase were synthesized by hydrothermal modification of TiO2carriers, and the doping of metal Bi was carried out by various methods on this basis. The performance and selectivity of the modified TiO2catalysts were evaluated by photothermal catalytic reduction of CO2and H2O, while the physicochemical properties and photochemistry were determined by XRD, Raman, BET, SEM, EDS mapping, TEM, XPS, UV–vis DRS, PL, TR-PL, CO2-TPD, and in situ DRFITS. The catalysts were analyzed by in situ characterization techniques to reveal the effects of carrier modification, semiconductor compounding, metal loading, and doping on the catalytic performance, physicochemical properties, and photothermal properties of the catalysts and then to explain the mechanism of CO2catalytic reduction, which provides theoretical guidance and data support to improve the selection and design of catalysts.

Photocatalytic research on conventional semiconductors has been conducted for many years, but the conversion efficiency of solar energy remains low. Conventional semiconductor/metal–organic framework (MOF) hybrid photocatalysts have emerged as an alternative approach to enhance solar energy utilization due to their porous and well-defined surface structures. In this study, we present a composite nanophotocatalyst with efficient CO2reduction capabilities driven by sunlight, referred to as ZIF-8@TiO2-NBS. This composite is prepared by externally decorating pure anatase-phase TiO2nanoribbons with zeolitic imidazolate framework-8 (ZIF-8) through ultrasonic synthesis, with careful modulation of their ratio. The resulting composite exhibits an impressive specific surface area (optimized at 1352.31 m2/g) and maintains a stable mesoporous structure. Exceptional CH4yield (29.53 μmol·g–1·h–1) and selectivity (71.97%) were achieved under solar irradiation. Further insights from X-ray photoelectron spectroscopy and in situ infrared tests indicate that the remarkable enhancement in the photocatalytic activity of ZIF-8@TiO2-NBS can be attributed not only to the well-designed surface structure but also to the synergistic effect between ZIF-8 and TiO2. This interaction leads to the redistribution of electron clouds and the creation of partial oxygen vacancy defects. Notably, the partnership between ZIF-8 and TiO2notably enhances the separation of photogenerated carriers and the stability of the composite catalysts. This is evident in the increased presence of crucial reaction intermediate species (*COOH) in the ZIF-8/TiO2composite catalysts, during both dark-adsorption and light-driven reaction phases. This study underlines the promising potential of combining MOFs with conventional semiconductor photocatalytic materials, providing theoretical insights and empirical data to further refine the selection and design of advanced photocatalysts.

With the development of human society, the discharge of various pollutants increases gradually, which gradually worsens the environment. Nowadays, the emission of pollutants is gradually under more strict control. Bismuth-based photocatalysts have attracted much attention due to their visible light response characteristics, unique layer structure and adjustable electron band structure. However, their photocatalytic performance is not satisfactory, which hinders their practical application. Therefore, many researches have been carried out to improve its photocatalytic performance. In this paper, the modification methods and mechanisms of bismuth-based photocatalysts and the strategies to improve the photocatalytic activity of these materials were reviewed, including the latest progress in the preparation and performance improvement of bismuth photocatalysts such as bismuth vanadate photocatalyst, bismuth halide photocatalyst, bismuth tungstate photocatalyst, bismuth titanate photocatalyst and so on. Various reaction mechanisms of bismuth photocatalyst were discussed in the hope of providing ideas for developing more efficient bismuth photocatalyst materials. Finally, the application prospect and challenges of bismuth-based photocatalytic materials are discussed.