Advances in asymmetric moist-electric generators with innovative heterogeneous structures

Abstract

Harvesting energy from the ubiquitous moisture induced streaming potential or ion concentration gradients is a promising green technology. Lately, the emergence of high-performance asymmetric moist-electric generators (AMEGs) with an inhomogeneous distribution of their moist-electric active layer has significantly propelled this field forward, as the asymmetric structures can effectively regulate the moisture adsorption and ion migration. Nonetheless, a profound comprehension of the interrelationship between the working mechanisms, materials, and device structures remains essential. In this review, we provide a comprehensive account of AMEGs spanning from their fundamental research to real-world applications. We initially delve into the fundamental mechanisms and material engineering strategies centered on asymmetric architectures. Subsequently, we discuss device design strategies and power applications of AMEGs. Lastly, we provide an analysis of the challenges, potential solutions, and future trajectory for this promising technology.