Heterogeneous Photocatalysis

Heterogeneous photocatalysis has gained considerable interest in recent years due to its promising potential for addressing challenges like environmental remediation, energy conversion, water splitting, CO 2 reduction, and organic synthesis. Recently, there have been several advances in heterogeneous photocatalysis, including the designing of novel photocatalysts, the optimization of photocatalytic processes, and the discovery of new applications, such as the use of nanoparticle-based photocatalysts, plasmonic photocatalysts, and 2D materials. Overall, recent advances in heterogeneous photocatalysis have opened new opportunities for using this technology to address a variety of energy and environmental related challenges. This process generally involves the use of a semiconductor material, typically titanium dioxide (TiO 2 ), which becomes energized by sunlight, resulting in the creation of electron-hole pairs. These pairs interact with surface molecules, leading to the formation of reactive oxygen species (ROS) and diverse chemicals. ROS assist in breaking down pollutants, splitting water into oxygen and hydrogen, and converting CO 2 . Nanoparticlebased photocatalysts provide a notable advantage with their substantial surface-area to volume ratio, thereby elevating their photocatalytic performance. Plasmonic photocatalysts utilize surface plasmon resonance to boost their efficiency in converting CO 2 , benefiting from their ability to absorb visible light, abundant in solar energy. Additionally, materials like graphene and transition-metal dichalcogenides, known as two-dimensional substances, have gained attention for their substantial surface areas and unique electronic properties, making them promising and versatile in various photocatalytic applications. Heterogeneous photocatalysis stands as a highly promising technological innovation, garnering significant attention in the realm of environmental remediation. This advanced technique has been subjected to extensive research and exploration due to its immense potential in the purification of both air and water environments. This chapter gives a brief summary of recent advances in heterogeneous photocatalysis and its applications. Initially, it delves into the fundamental principles underpinning photocatalysis, encompassing a comprehensive examination of photocatalyst categories, the mechanisms governing photocatalysis, and the factors that influence its efficiency. Subsequently, it explores the diverse applications of heterogeneous photocatalysis, spanning pollutant degradation, CO 2 reduction, water splitting, and organic synthesis. Next, various applications of heterogeneous photocatalysis, such as pollutant degradation, CO 2 reduction, water splitting, and organic synthesis, are reviewed. The mechanisms and challenges associated with each application are discussed along with recent advances in enhancing the photocatalytic performance of catalysts. Finally, chapter discusses the future directions and challenges in heterogeneous photocatalysis highlighting the importance of heterogeneous photocatalysis in addressing global environmental and energy challenges.