Fig. 5: The germanium/perovskite heterojunction photodetector energy band model and optical characterization.

a Energy-band diagrams for two isolated semiconductors and heterojunction device (type I energy band). b Time-resolved PL decay and intensity (inset) comparison for the pristine and hetero-structure perovskite. c Iph-V curves for pristine perovskite and heterojunction photodetector.