Optimization of ion transport in two-dimensional nanofluidic membranes for osmotic energy conversion

Osmotic energy, a promising renewable energy source, is generated by selective ion transport driven by the salinity gradient between seawater and river water. Selective and ultrafast ion transport is highly desirable for osmotic energy conversion. Due to the amazing diversity of designable nanochannels, two-dimensional (2D) nanofluidic membranes can precisely regulate ion transport to optimize osmotic energy conversion, opening up new avenues for osmotic energy conversion. Here, we summarize the strategies to optimize ion transport within 2D nanofluidic membranes to enhance osmotic energy conversion. Firstly, we introduce ion transport pathways and mechanisms within 2D nanofluidic membranes. Subsequently, we survey different strategies to improve ion transport for optimizing 2D nanofluidic membranes. Following this, we discuss the applications of osmotic energy and its integration with other technologies. Finally, we outline the obstacles to the development of osmotic energy conversion and propose some perspectives for future applications.