Regulation of V2O5 layer spacing by controlling H2O/C2H5OH ratio in hydrothermal process for application in electrochemical conversion of salinity gradient energy

Abstract

Another abundant source of renewable energy exists in the oceans, where the chemical energy released from the mixing of seawater and river water is known as salinity gradient energy or blue energy. Salinity gradient energy is a sustainable, clean and renewable energy source that produces electricity without emitting greenhouse gasses or other pollutants. In this work, we constructed a new salinity gradient energy extraction device by preparing V2O5 in a very simple way by controlling H2O/C2H5OH ratio in hydrothermal process and using the V2O5 as an anode to obtain salinity gradient energy by utilizing the salinity change of the solution and thus the potential difference power generation. The results show that ethanol forms hydrogen bonds or van der Waals forces with the layered material, which enters the interlayer to enlarge the spacing between the layers of V2O5 and further increase the electrochemical properties of V2O5. The maximum energy density produced by the device was 6.29 J g−1 after one complete cycle. The device is environmentally friendly with low cost, easy to synthesize raw materials and does not use ionic membranes, which provides a new way to harvest the salinity gradient energy.