Jump to main content
Jump to site search


Weak Temperature-Dependent Hole Injection and Electron-Hole Recombination at CH3NH3PbI3/NiO Heterojunction: A Time-Domain Ab Initio Study

Abstract

Inorganic hole transport material (HTM) NiO is superior to the traditional organic HTMs due to the high stability and conductivity. Efficient charge separation and slow charge recombination are two key important steps in determining the efficiency of solar cells but they often show strong temperature dependence. Using nonadiabatic molecular dynamics combined with ab initio time-domain density functional theory, we have demonstrated that the time scales for both hole transfer and electron-hole recombination show weak temperature-dependent in MAPbI3/NiO perovskite solar cells. The hole transfer occurs on sub-100fs at both and high and low temperature. Hole transfer proceeds slightly faster at high temperature than low temperature due to enhanced NA coupling. Notably, the over 200 fs energy relaxation remains the hole hot before cooling to interacting with the remaining electron and forming exciton and accelerating electron-hole recombination, providing an excellent advantage for solar energy applications. Following charge separation, the electron-hole recombination takes place on several nanoseconds at both low and high temperature. The acceleration is only by a factor of below 2 arises due to that increased atomic motions cause rapid loss of coherence, which competes successfully with the enhanced NA coupling. The detailed atomistic understanding of the reported results allows us to generalize the conclusions to other hole transport materials, and suggest weak temperature-dependent charge dynamics properties enabling high performance of perovskite solar cells.

Back to tab navigation

Supplementary files

Publication details

The article was received on 26 Oct 2019, accepted on 26 Nov 2019 and first published on 27 Nov 2019


Article type: Paper
DOI: 10.1039/C9TA11789J
J. Mater. Chem. A, 2019, Accepted Manuscript

  •   Request permissions

    Weak Temperature-Dependent Hole Injection and Electron-Hole Recombination at CH3NH3PbI3/NiO Heterojunction: A Time-Domain Ab Initio Study

    J. He, W. Fang and R. Long, J. Mater. Chem. A, 2019, Accepted Manuscript , DOI: 10.1039/C9TA11789J

Search articles by author

Spotlight

Advertisements