Abstract
Salinity gradient energy, which is abundant along the coastline in ocean, is a kind of chemical energy existing the solutions of different concentrations mixing. The pressure retarded osmosis, reverse electrodialysis and accumulator mixing technology are currently the most common approaches to harvest salinity gradient energy. Here we report an electrochemical device using active carbon as anode and manganese phosphate as cathode for salinity gradient energy harvesting, which shows an energy density of 5.31 J g−1, indicating a potential application in the field of ocean energy utilization.