Open AccessNanoscale control of grain boundary potential barrier, dopant density and filled trap state density for higher efficiency perovskite solar cells
Author(s) -
Bahrami Behzad,
Mabrouk Sally,
Adhikari Nirmal,
Elbohy Hytham,
Gurung Ashim,
Reza Khan M.,
Pathak Rajesh,
Chowdhury Ashraful H.,
Saianand Gopalan,
Yue Wenjin,
Zai Jiantao,
Qian Xuefeng,
Liang Mao,
Qiao Qiquan
Publication year - 2020
Publication title -
infomat
Language(s) - English
Resource type - Journals
ISSN - 2567-3165
DOI - 10.1002/inf2.12055
Subject(s) - perovskite (structure) , dopant , grain boundary , relative humidity , materials science , rectangular potential barrier , trap (plumbing) , chemistry , doping , optoelectronics , crystallography , composite material , thermodynamics , physics , meteorology , microstructure
In this work, grain boundary (GB) potential barrier ( Δφ GB ), dopant density ( P net ), and filled trap state density ( P GB,trap ) were manipulated at the nanoscale by exposing the fabricated perovskite films to various relative humidity (RH) environments. Spatial mapping of surface potential in the perovskite film revealed higher positive potential at GBs than inside the grains. The average Δφ GB , P net , and P GB,trap in the perovskite films decreased from 0% RH to 25% RH exposure, but increased when the RH increased to 35% RH and 45% RH. This clearly indicated that perovskite solar cells fabricated at 25% RH led to the lowest average GB potential, smallest dopant density, and least filled trap states density. This is consistent with the highest photovoltaic efficiency of 18.16% at 25% RH among the different relative humidities from 0% to 45% RH.