Polyimide-based photocatalysts: rational design for energy and environmental applications

Semiconductor photocatalysis is a promising technology to address both energy and environmental issues. Polymer semiconductors have emerged as a new class of heterogeneous photocatalysts owing to their inherent advantages of low cost, earth abundant nature, facile synthesis, easy functionalization, molecularly tunable optoelectronic properties, and high physicochemical stability. Polyimide (PI), a conventional polymer widely used in separation, coating, aerospace and microelectronics industries, has recently received considerable attention for photocatalytic applications. In this review, we present a comprehensive summary of the development of PI-based photocatalysts. First, a brief introduction of synthetic methods of PI is given. Then, we present and categorize several strategies, including co-monomer tuning, element/molecular doping, micro/nanostructure engineering, and junction engineering, that are relevant to physicochemical properties and photocatalytic activities. Moreover, various applications of PI-based photocatalysts, such as photocatalytic H(2)evolution, photodegradation of organic contaminants, H(2)O(2)photosynthesis from H2O and O-2, and photocatalytic organic transformation are summarized. Special emphasis is placed on the structure-property relationships for designing polymer photocatalysts with improved photocatalytic performance. Finally, we discuss the future development and prospects for PI-based photocatalysts.