MXene membranes and their use in osmotic energy generation

Abstract Osmotic energy generation has demonstrated significant potential for its use as an alternative renewable energy. In particular, reverse electrodialysis (RED) which exploits a semipermeable membrane to convert osmotic energy into electricity. Recent studies have shown that the use of nanofluidic membranes assembled from two-dimensional (2D) nanosheets in RED systems enhances output power density (P) and energy conversion efficiency (η). MXene membranes, assembled from MXene nanosheets, exhibit highly ordered nanofluidic channels and superior cation-selective permeability, promising candidates for advancing membrane-based RED technologies. In this review, we begin with the preparation and structure of MXene membranes, which dictate the membrane permeance and selectivity and subsequently the P and η for osmotic energy generation. Then we review the application performance of MXene membranes in osmotic energy generation. Finally, we offer a perspective on the research directions for MXene membranes in the advancement of osmotic energy generation technologies.