A bandgap-tunable KNbO₃ ferroelectric ceramic was prepared by introducing Bi/Co ion. The existence of mixed valence states of Co²⁺/Co³⁺ in the system induced the bandgap reduction and its tunable behavior. KNbO₃–BiCoO₃ solid solutions showed a typical orthogonal perovskite structure and maintained good ferroelectricity (P_s = 15.13 µC/cm²) and high-field polarization ability. The devices based on the .98KNbO₃–.02BiCoO₃ sample exhibited an improved short-circuit photocurrent density (J_sc) of 19.2 nA/cm² under simulated solar radiation, and this was further enhanced to 79.8 nA/cm² after a 60-kV/cm polarizing. The structural analysis of the samples after polarization reveals the effect of ferroelectric polarization on photovoltaic performance. This work provides new insights into the effects of ferroelectric polarization on photovoltaic performance.

中文翻译：

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通过 Bi/Co 共掺杂 KN 基铁电陶瓷中的极化增强光伏性能

通过引入Bi/Co离子制备了带隙可调的KNbO _{3铁电陶瓷。}^{系统中Co 2+} /Co ³⁺混合价态的存在导致了带隙减小及其可调行为。KNbO ₃ –BiCoO ₃固溶体呈现典型的正交钙钛矿结构，并保持良好的铁电性（P _s  = 15.13 µC/cm ²）和高场极化能力。基于 .98KNbO ₃ –.02BiCoO ₃样品的器件表现出改善的短路光电流密度 ( J _sc ) 为 19.2 nA/cm ²在模拟太阳辐射下，在 60-kV/cm 偏振后进一步提高到 79.8 nA/cm ^{2 。}极化后样品的结构分析揭示了铁电极化对光伏性能的影响。这项工作为铁电极化对光伏性能的影响提供了新的见解。