Advances in Photocatalytic CO ₂ Conversion and Reduction Under Solar Energy Irradiation: An Overview

ABSTRACT The increasing energy crisis and worsening global climate caused by the excessive use of fossil fuels have driven extensive research into carbon dioxide (CO 2 ) capture, storage, and utilization. Among these, artificial photosynthesis, which harnesses solar energy to convert CO 2 into valuable and renewable fuels like methane or methanol, has gained significant attention. It begins by discussing the fundamental concepts, including the role of solar energy in driving the conversion process and the types of photocatalysts used. The review highlights recent advancements in developing more efficient photocatalysts, emphasizing the importance of light harvesting and the enhancement of photogenerated charge carriers. These improvements are crucial for increasing the efficiency and selectivity of the CO 2 conversion process. Furthermore, the review delves into the underlying mechanisms of CO 2 photoreduction. It examines key aspects such as the adsorption of reactants onto the catalyst surface, the activation of CO 2 molecules, and the possible reaction pathways that lead to the formation of desired products. Selected examples are provided to illustrate these mechanisms, offering insights into how different catalysts and conditions influence the photoreduction process. In addition to reviewing current progress, the article also outlines future research directions and identifies open issues in the field of CO 2 photoreduction.