Electron‐Selective Passivation Contacts for High‐Efficiency Nanostructured Silicon Hydrovoltaic Devices

Abstract

Abstract The hydrovoltaic effect is a recently‐developed means to directly generate electric power from omnipresent water resources, which has drawn substantial attention in the energy harvesting and conversion domain. Unfortunately, the output power density significantly lags behind the other power generation ways. Although numerous efforts have been made to develop various active materials catering to improved output, yet less attention has been paid to the interface between active materials and electrodes. Here, an atomic layer deposition deposited titanium oxide layer is incorporated at rear silicon contact, enabling high surface passivation quality and superior electron selectivity characteristics. As a consequence, the passivated rear contact remarkably enables elevated hydrovoltaic performance, yielding a high open‐circuit voltage of ≈0.82 V and a short‐current density of ≈30 µA cm −2 at room temperature, and the output power density of ≈15 µW cm −2 displays the highest value among previously reported comparable hydrovoltaic devices. This finding that regards the leverage of transition metal oxide as a passivation layer presents a prospective avenue to improve interfacial contact for high‐efficiency hydrovoltaic devices.