Multifunctional hydrogels for sustainable energy and environment

Abstract This review gives an overview of the research presented in the lecture by Professor Guihua Yu for the 2020 Polymer International‐IUPAC Award for Creativity in Polymer Science. Hydrogels with intriguing physicochemical properties emerge as an attractive materials platform for sustainable energy storage and conversion as well as clean water production. Here we describe some highlights of key building blocks and synthetic approaches of hydrogel‐based materials in a tunable manner from bulk to the molecular scale. Various strategies for improving electronic/ionic conductivity, controlling swelling/deswelling behaviors and integrating multiple functionalities are discussed. Specific examples of recent achievements of hydrogels for applications in batteries, supercapacitors, electrocatalysis, solar evaporators and moisture harvesters are presented. These multifunctional hydrogels with highly tailorable architectures and physicochemical properties will become useful in next‐generation sustainable energy and water technologies. © 2021 Society of Industrial Chemistry.