Conductive hydrogels for bioenergy harvesting and self-powered application

Conductive hydrogels (CHs) are characterized by tissue-like mechanical properties, multiple stimuli-responsive abilities and favourable biocompatibility, enabling their wearable devices to construct a conformal interface with rugged tissue surfaces compatible with human body for real-time monitoring. However, external power supply requirements and complex fabrication processes limit their broad applications. Self-powered wearable devices can harvest energy from humans and the ambient environments, benefitting a long-term operating ecosystem. In this review, we discuss the materials engineering and designs for CHs-based devices for bioenergy harvesting and self-powered application. Specifically, we highlight the unique advantages of CHs in bioelectrical interfacing with the human body. CHs-based flexible bioenergy harvesters as well as self-powered applications are then summarized. Finally, we will provide the current challenges for materials, device designs and feasible approaches in the next-generation CHs-based multifunctional devices.