with a strongly absorbing mixed-halide perovskite and introducing ZnO as an electron transport layer, a favorable energy cascade is formed, which is consistent with selective carrier separation under zero bias. Comparative studies reveal that the ZnO interlayer significantly suppresses dark current, enhances rectification behavior, and improves zero-bias photocurrent by facilitating selective electron extraction and suppressing interfacial recombination. The optimized device exhibits stable switching characteristics and uniform pixel-to-pixel response, enabling reliable self-powered imaging. This work clarifies the critical role of transport-layer-assisted interface modulation in vertical 2D/3D heterojunctions and provides a scalable strategy for constructing high-performance, energy-efficient photodetector arrays.
Tang et al. (Tue,) studied this question.