Ultrahigh stability photovoltaic performance of M-Mo⁶⁺ (M=Fe³⁺, Co²⁺, Ni²⁺) co-doped BiVO₄ films

BiVO₄ has been widely studied in photovoltaic conversion. However, as a paraelectric material, BiVO₄ lacks an internal electric field for efficient carrier separation, resulting in low photocurrent and limited practical use. Enhancing the photovoltaic performance of thin films through simple methods is challenging. In this paper, M-Mo⁶⁺ (M=Fe³⁺, Co²⁺, Ni²⁺) ions were used to co-doped BiVO₄ films, which were then composited with NiO to construct composite film structures. The NiO/Bi_0.985Co_0.015V_0.985Mo_0.015O₄ film achieved a photocurrent density (J_sc) of 2.33 mA/cm² and an open-circuit voltage (V_oc) of 0.39 V. The film also demonstrated a specific detection rate of 2.67 × 10¹¹ jones at an optical power density of 165 mW/cm² and maintained 1.94 × 10¹¹ jones at 103.7 mW/cm². At an optical power density of approximately 140 mW/cm², the specific detection rate begins to decrease. The photovoltaic conversion performance of the film exhibits high stability over a long period of time (＞10,000 s). The thin films maintain good photovoltaic performance at high temperatures. This work provides an approach for the application of BiVO₄ in photovoltaics.