A hybrid energy cell for self-powered water splitting

Abstract

Production of hydrogen (H₂) by splitting water using the electrolysis effect is a potential source of clean and renewable energy. However, it usually requires an external power source to drive the oxidation or reduction reactions of H₂O molecules, which largely limits the development of this technology. Here, we fabricated a hybrid energy cell that is an integration of a triboelectric nanogenerator, a thermoelectric cell, and a solar cell, which can be used to simultaneously/individually harvest mechanical, thermal, and/or solar energies. The power output of the hybrid energy cell can be directly used for splitting water without an external power source. The volume of the produced H₂ has a linear relationship with the splitting time at a production speed of 4 × 10⁻⁴ mL s⁻¹. Moreover, the produced energies can also be stored in a Li-ion battery for water splitting as well as other uses.