1 - Advanced materials for photocatalytic applications: the challenge ahead

Abstract

Photocatalytic nanomaterials have recently received great interest due to their potential applications in many activities related to environmental protection, energy conversion and chemical reactions. The factors determining the performance of the photocatalytic materials are the bandgap, behavior of photogenerated charge carriers and adsorptivity. Much research has been conducted on these three factors recently, in order to enhance the novel photocatalytic nanomaterials. Even though carbon nanomaterials such as carbon nanotubes and fullerenes have proven their capability for their use in electronic applications, hybridizing the carbon nanomaterials with photoactive nanomaterials has been actively investigated by many researchers for enhancing their photocatalytic activity. On the other hand, graphitic carbon nitride—one of the multitudinous types of photocatalysts—has also gained attention for photocatalytic applications. Nonmetal group–doped porous ultrathin graphitic carbon nitride nanosheets have been explored by few research groups to improve photocatalytic efficiency. Polymeric nanocomposites also need to be studied to explore the insight of the excitonic processes for their potential photocatalytic applications. Optimization of the band structures and charge separation are the key tools for the regulation of hot-carrier generation useful in photocatalysts. Visible light responsive photocatalysts are of very much importance for effective conversion of solar energy. In the current context, it seems a great challenge to use such materials for commercial applications, especially in terms of low surface area, limitation of the active sites, recombination of the photogenerated charge carriers, and optical absorption. This chapter deals with many aspects of the photocatalytic nanomaterials currently under active research, and their challenges for utilization in photocatalytic activities.