Photocatalytic radical species: An overview of how they are generated, detected, and measured

The development, and demonstration of efficiencies, of photocatalytic technologies are often dependent on the method by which activity is measured. The screening of both materials and reactors is a key aspect in the development process and both are critical in determining whether the technology is suitable for a required application. Given this, detection and quantification of radical species produced during photocatalysis have become an area of increasing interest. As a result, several direct and indirect methods have been developed to measure reactive oxygen species such as O2•−, •OH, and H2O2. This chapter explores these approaches including their advantages, limitations, and whether they are accurate as a representation of photocatalytic activity.