Simulations on photovoltaic conversion in perovskite solar cells by solving hierarchical equations of motion

Hui Cao,Shurong Wang,Mingdao Zhang,Tao Tao,Jing Ma,Jinwei Sun

doi:10.1063/1.5095799

Abstract

Understanding the mechanism of photovoltaic conversion in perovskite solar cells (PSCs) remains a great challenge. In this work, we have simulated the charge generation, transport and recombination in PSCs under standard AM 1.5G sunlight on the basis of solving hierarchical equations of motion with model Hamiltonian. Reasonable current/voltage characteristics, power conversion efficiency (PCE), and incident photon to current conversion efficiency (IPCE) can be obtained by investigating different interaction with respect to the interfacial recombination. Moreover, it is found that the interfacial charge transfer (CT) states can greatly affect the current/voltage characteristics, which is elucidated by analyzing the density of states. Dynamics response of current to sunlight or bias is demonstrated and the intrinsic temperature effect on PCE is also discussed.

Highlights

Environmental pollution at the present time is largely due to the excess use of the fossil energy resources
The efficiency of perovskite solar cells (PSCs) over 23% has been achieved in the recent years,6 and continuous improvement in fabrication technology of PSCs7–11 makes it possible to quickly approach the physical limit of photoelectric conversion given by Shockley and Queisser half a century ago
As it changes from 0.14 eV to 0.06 eV, the open-circuit voltage (Voc) increases from 1.002 V to 1.141 V, and the fill factor (FF) increases from 72.66% to 73.54%, respectively

Summary

Introduction

Environmental pollution at the present time is largely due to the excess use of the fossil energy resources. It is urgent to look for alternative sources of energy with less or no emissions. The organometal PSCs stand for such a direction which has already attracted tremendous attention around the world.. The efficiency of PSCs over 23% has been achieved in the recent years, and continuous improvement in fabrication technology of PSCs7–11 makes it possible to quickly approach the physical limit of photoelectric conversion given by Shockley and Queisser half a century ago.. Theoretical research, especially, the dynamics simulation on PSCs lags behind the experiments. Most of the dynamics simulations focused on the organic solar cells.

Methods

Results

Conclusion