Boosting power conversion efficiency by hybrid triboelectric nanogenerator/silicon tandem solar cell toward rain energy harvesting

The weather-dependence and intermittent photoelectric conversion capacity of the traditional photovoltaics call for rational design on device architecture to realize persistent power output under multiple-energy-source stimuli. Herein, we demonstrate a novel triboelectric nanogenerator/silicon (TENG/Si) tandem hybrid solar cell by stacking top silver/polydimethylsiloxane sub-cell onto bottom monocrystalline Si solar cell for simultaneously harvesting solar and rain energies. Upon systematically optimizing the device configuration and the properties of top nanogenerator, the bottom Si solar cell is used as a friction layer to regulate the charge distribution of TENG, achieving a short-circuit current of 7.59 μA, a peak open-circuit voltage of 37.19 V under the stimuli of single raindrop and a power conversion efficiency enhancement by 20% in comparison with pristine Si solar cell. Finally, 26 blue light-emitting diodes can be lighted up by one raindrop. Given the compelling advantages of enhanced power output and expanded working time, this physical proof-of-concept TENG/Si tandem hybrid solar cell provides new opportunities to collect multiple energies from nature and to promote the development of weather-independent solar cells.