Oxygen Vacancies Mediated Co‐Sputtered Ti‐Doped BiVO₄ Thin Films‐Based Transparent Photovoltaic Device

Abstract

BiVO4, a narrow bandgap material (2.5 eV), has been widely explored for photocatalytic applications, but its applications in the optoelectronic field are unexplored. This work explores BiVO4 for photovoltaic devices using the oxygen vacancies mediated co‐sputtered Ti‐doped BiVO4 (Ti:BiVO4) that exhibits on‐site power production by photovoltaics and see‐through features. The structural, chemical, and optical properties of Ti:BiVO4 are investigated for heterojunction formation with p‐type NiO film. The sputtering power of Ti plays a significant role in improving the light absorption capability by increasing oxygen vacancy concentration, enhancing the device performance. The devices show an open‐circuit voltage value of 676 mV and a short‐circuit current density value of 4.83 mA cm−2 with a maximum power production value of 122.2 µW under UV illumination of intensity 53.1 mW cm−2. The obtained device performances correlate with the Ti dopant's deposition power that tunes the structural and optical properties of BiVO4 films. Moreover, in self‐powered mode, the fabricated devices show a fast photoresponse speed of 0.8 ms with a high detectivity value of 2.22 × 1012 Jones. This work establishes the suitability of co‐sputtered Ti:BiVO4 for the next generation of transparent self‐powered optoelectronic devices.