Promising applications of wide bandgap inorganic perovskites in underwater photovoltaic cells

Power supply for underwater devices such as vehicles, sensors and autonomous systems is an important factor which limits their practical application. Solar energy is a promising energy source but high-efficient solar cells on land cannot maintain their original superiority for the change of underwater solar irradiance caused by absorption and scattering in water. Here, we investigate the solar irradiance for water with different clarity and discuss the potential applications of different materials in underwater photovoltaic cells. By calculating and comparing the device performance of underwater solar cells (UWSCs) with different bandgap, it is demonstrated that wide bandgap (1.8 eV-2.3 eV) inorganic perovskite solar cells (IPSCs) have significant advantages for underwater applications due to its outstanding photoelectric properties and suitable range of bandgap. The IPSCs can obtain the power conversion efficiency (PCE) of 41.9% and power density of 3.11 mW/cm2 at the depth of 50 m in water, which is obviously higher than silicon solar cells. No matter what types of water we choose, the optimal bandgap of UWSC’s active layer get wider with the increasing of water depth and the wide bandgap inorganic perovskites with 2.0–2.2 eV is an optimal choice. Our work reveals the significance of IPSCs in underwater photovoltaic applications.