In-Plane Oriented Ch3nh3pbi3 Nanowire Suppression Of The Interface Electron Transfer To Pcbm*

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-MAPbI(3))/Phenyl C61 butyric acid methyl-ester synonym (PCBM), as well as the interface of compact CH3NH3PbI3(C-MAPbI(3))/PCBM by transient absorption spectroscopy. By comparing the carrier recombination dynamics of N-MAPbI(3), N-MAPbI(3)/PCBM, C-MAPbI(3), and C-MAPbI(3)/PCBM from picosecond (ps) to hundred nanosecond (ns) time scale, it is demonstrated that electron transfer at N-MAPbI(3)/PCBM interface is less efficient than that at C-MAPbI(3)/PCBM interface. In addition, electron transfer efficiency at C-MAPbI(3)/PCBM interface was found to be excitation density-dependent, and it reduces with photo-generation carrier concentration increasing in a range from 1.0 x 10(18) cm(-3)-4.0 x 10(18) 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 x 10(18) cm(-3)-2.2 x 10(18) cm(-3).