One-dimensional nanowire is an important candidate for lead-halide perovskite-based photonic detectors and solar cells.Its surface population,diameter;and growth direction,etc.,are critical for device performance.In this research,we carried out a detailed study on electron transfer process at the interface of nanowire CH3NH3PbI3(N-MAPbI3)/Phenyl C61 butyric acid methyl-ester synonym (PCBM),as well as the interface of compact CH3NH3PbI3(C-MAPbI3)/PCBM by transient absorption spectroscopy.By comparing the carrier recombination dynamics of N-MAPbI3,N-MAPbI3/PCBM,C-MAPbI3,and C-MAPbI3/PCBM from picosecond (ps) to hundred nanosecond (ns) time scale,it is demonstrated that electron transfer at N-MAPbI3/PCBM interface is less efficient than that at C-MAPbI3/PCBM interface.In addition,elec-tron transfer efficiency at C-MAPbI3/PCBM interface was found to be excitation density-dependent,and it reduces with photo-generation carrier concentration increasing in a range from 1.0 × 1018 cm-3-4.0 × 1018 cm-3.Hot electron transfer,which leads to acceleration of electron transfer between the interfaces,was also visualized as carrier concentration increases from 1.0 × 1018 cm-3-2.2 × 1018 cm-3.