Photocatalytic and Photoelectrochemical Systems: Similarities and Differences

• Published in: Advanced materials (Weinheim) Vol. 32; no. 18; pp. e1904717 - n/a
• Main Authors: Wu, Hao, Tan, Hui Ling, Toe, Cui Ying, Scott, Jason, Wang, Lianzhou, Amal, Rose, Ng, Yun Hau
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 01-05-2020
• Subjects: Analogies; Energy harvesting; Materials science; mechanism similarity; Performance enhancement; photoactive materials; Photocatalysis; photocatalysts; photoelectrochemical systems; Semiconductors; solar energy conversion; system performance; water splitting; solar energy conversion; water splitting; mechanism similarity; photocatalysts; photoactive materials; photoelectrochemical systems; system performance
• ISSN: 0935-9648; 1521-4095
• DOI: 10.1002/adma.201904717

Photocatalytic and photoelectrochemical processes are two key systems in harvesting sunlight for energy and environmental applications. As both systems are employing photoactive semiconductors as the major active component, strategies have been formulated to improve the properties of the semiconductors for better performances. However, requirements to yield excellent performances are different in these two distinctive systems. Although there are universal strategies applicable to improve the performance of photoactive semiconductors, similarities and differences exist when the semiconductors are to be used differently. Here, considerations on selected typical factors governing the performances in photocatalytic and photoelectrochemical systems, even though the same type of semiconductor is used, are provided. Understanding of the underlying mechanisms in relation to their photoactivities is of fundamental importance for rational design of high‐performing photoactive materials, which may serve as a general guideline for the fabrication of good photocatalysts or photoelectrodes toward sustainable solar fuel generation.
Photoactive semiconductors have been extensively used in solar energy conversion applications. They are typically employed in either photocatalytic or photoelectrochemical systems. Although some generic strategies to improve the materials have been formulated, the requirements to achieve excellent activities are different in both processes. Insightful discussions on the aspects for consideration in developing excellent photocatalytic and photoelectrochemical systems are provided.