Bismuth ferrite (BFO) with narrow bandgap (<2.70 eV) is an uprising star in the application of optoelectronic conversion in visible (Vis) region. Fe-site doping by transition metals is a recognized strategy to reduce leakage current in order to create more qualified BFO-based optoelectronic devices. We aim to constitute the heterostructure of BiFe_1-xCr_xO₃ (BFCO) coupling to hole-transporter NiO, serving as Vis-active photodetector with superior photoresponse speed. The influence of Cr doping ratio on BFCO is systematically investigated, indicating that doping Cr can effectively restrain not only the reduction of Fe³⁺ state but also the generation of oxygen vacancies. Moreover, by taking advantage of desirable energy-band alignment, BFCO/NiO heterojunction can reach the optimized response time constants of photocurrent rising and decay, i.e., τ_r and τ_d are, respectively, lowered down to 0.23 and 0.38 ms, which are almost two order-of-magnitude lower than that of pure-BFO/NiO and also more than one order-of-magnitude lower than that of single-layer BFCO film. It confirms an overwhelming photoresponse performance over other Vis-active counterparts. Herein, we for the first time achieve the Vis photodetector based on BFCO, by virtue of functional interfacial structure of BFCO-NiO to energetically separate photogenerated electron–hole pairs as well as improve charge carrier transportation.

具有窄带隙（<2.70 eV）的铁酸铋（BFO）是可见光（Vis）区光电转换应用中的一颗冉冉升起的新星。通过过渡金属进行 Fe 位点掺杂是一种公认​​的减少漏电流的策略，以创建更合格的基于 BFO 的光电器件。我们的目标是构建与空穴传输体 NiO 耦合的BiFe _{1- x} Cr _x O _{3 (BFCO) 异质结构，作为具有优异光响应速度的可见光活性光电探测器。}系统研究了Cr掺杂比对BFCO的影响，表明掺杂Cr不仅可以有效抑制Fe ^3+的还原状态也是氧空位的产生。此外，通过利用理想的能带排列，BFCO/NiO 异质结可以达到光电流上升和衰减的优化响应时间常数，即τ _r和τ _d分别降低到 0.23 和 0.38 ms，比纯 BFO/NiO 低近两个数量级，也比单层 BFCO 薄膜低一个数量级以上。它证实了压倒性的光响应性能优于其他 Vis-active 对应物。在此，我们首次实现了基于 BFCO 的 Vis 光电探测器，凭借 BFCO-NiO 的功能界面结构来有效分离光生电子 - 空穴对并改善电荷载流子传输。