Fig. 5: Working principle and application of the IENG.

a Power generation principle for the IENG induced by water evaporation: (i) Schematic diagram of water flowing path and evaporation in the IENG, (ii) The left represents schematic diagram of the initial stage, which depicts the specific ion distribution within the channel. And the right is the schematic diagram of the steady state, which depicts the ion transportation in the overlapping electric double layer. b Water evaporation rate of the IENG in a simulated marine environment. The normal environment had a 1.0 kW· m⁻² light intensity, no wind and deionized water, and the optimized environment had a 2.0 kW· m⁻² light intensity, a 1 m s⁻¹ wind speed and seawater. c Output power density of the IENG measured under different load resistances. d Comparison of power density generated by the IENG and other solar-driven IENGs. e Photograph of a developed self-powered working system. The error bars represent standard deviations.