An all-weather solar cell that can harvest energy from sunlight and rain

Future solar cells may produce electricity in all weathers. We present here a cost-effective and high-efficiency graphene based conducting composite tailored all-weather solar cell that can be actuated with raindrops and sunlight. Due to the formation of π-electron|cation double-layer pseudocapacitance at conducting composite/raindrop interface, the delocalized π-electrons on graphene can migrate along percolating pathways forward at spreading process and backward at shrinking periods, resulting in charging and discharging of the pseudocapacitor. The optimized solar cell yields a photoelectric conversion efficiency of 9.8% under simulated sunlight irradiation (air mass 1.5, 100   mW   cm −2 ) as well as current over several microamps and voltage of hundreds of microvolts under simulated raindrops. This work could extend our knowledge of future all-weather solar cells.