Power generation from concentration gradient in ion selective nanochannels

Ion selective nanochannels are studied to generate electric power from concentration gradient by reverse electrodialysis. We experimentally investigated the power generation from nanochannels with the channel height of 4nm placed between two potassium chloride solutions with various combinations of concentrations. The power generation per unit channel volume increases when the concentration gradient increases. The highest power density measured is 230㎾/㎥. Our data also indicates that the efficiency of energy conversion and the ion selectivity increase with a decrease of concentrations. The best efficiency obtained is 31%.