The Role of Metals in Nanocomposites for UV and Visible Light-Active Photocatalysis

Photocatalysis has emerged as a promising tool to perform various applications such as water splitting, inert molecular excitation, harnessing solar energy for chemical as well as biochemical activities, and developing various photocatalytic devices. The driving force behind the synthesis using light is that it is reliable, abundant, and a green source of energy. In the past decade, there is an immense increase in interest in exploring the use of metal nanoparticles in photocatalysis. Among many nanoparticle systems exploited for catalysis, plasmonic photocatalysts are one of the most intensely investigated due to their potential applications in energy materials. The shift of interest has been taking place to utilize the electromagnetic properties of metal or plasmonic nanoparticles than their traditional use as co-catalyst in various chemical processes. Photocatalysis consists of the direct conversion of light energy into chemical energy and thus reducing energy consumption. Metal nanoparticles (Ag, Au, Pd, or Pt) photocatalyst is very efficient, for example, in transforming renewable solar energy to chemical energy. Apart from catalytic applications, these nanocomposites are perceived to be environment-friendly, an attribute, which is becoming more relevant in recent times. This book chapter mainly discusses the mechanisms and applications of photocatalytic activity of nanocomposites composed of metal-based nanomaterials.