Construction of Nanochannel Membranes: Asymmetric Effect and Modulation for Enhanced Osmotic Energy Conversion

Osmotic energy, which is harnessed through the selective transportation, represents a carbon-neutral and highly scalable power generation mechanism with significant potential for global energy systems. Nanochannel membranes, as a crucial interface for converting osmotic energy, are constructed from a diverse array of emerging building blocks. These building blocks facilitate a range of innovative fabrication methodologies, which are predicated on asymmetric effects to modulate ion transport kinetics and thereby optimize the efficiency of energy conversion. This review aims to provide a comprehensive analysis of the field by exploring the characteristics of various building blocks, categorizing the construction strategies, examining asymmetric effects and corresponding strategies in geometric structures and chemical potential gradients, and offering an extensive overview of the regulatory landscape for high-performance applications. Our objective is to present a detailed and thorough review of the progress and future perspectives in the development of nanochannel membranes for osmotic energy conversion, thereby contributing to the advancement of sustainable energy technologies.