TY - JOUR
T1 - In-situ Observation of Trapped Carriers in Organic Metal Halide Perovskite Films with Ultra-Fast Temporal and Ultra-High Energetic Resolutions
AU - Kobbekaduwa, Kanishka
AU - Shrestha, Shreetu
AU - Adhikari, Pan
AU - Liu, Exian
AU - Coleman, Lawrence
AU - Zhang, Jianbing
AU - Shi, Ying
AU - Zhou, Yuanyuan
AU - Bekenstein, Yehonadav
AU - Yan, Feng
AU - Rao, Apparao
AU - Tsai, Hsinhan
AU - Beard, Matthew
AU - Nie, Wanyi
AU - Gao, Jianbo
N1 - Publisher Copyright:
© 2021, The Author(s).
PY - 2021/12/1
Y1 - 2021/12/1
N2 - We in-situ observe the ultrafast dynamics of trapped carriers in organic methyl ammonium lead halide perovskite thin films by ultrafast photocurrent spectroscopy with a sub-25 picosecond time resolution. Upon ultrafast laser excitation, trapped carriers follow a phonon assisted tunneling mechanism and a hopping transport mechanism along ultra-shallow to shallow trap states ranging from 1.72–11.51 millielectronvolts and is demonstrated by time-dependent and independent activation energies. Using temperature as an energetic ruler, we map trap states with ultra-high energy resolution down to < 0.01 millielectronvolt. In addition to carrier mobility of ~4 cm2V−1s−1 and lifetime of ~1 nanosecond, we validate the above transport mechanisms by highlighting trap state dynamics, including trapping rates, de-trapping rates and trap properties, such as trap density, trap levels, and capture-cross sections. In this work we establish a foundation for trap dynamics in high defect-tolerant perovskites with ultra-fast temporal and ultra-high energetic resolution.
AB - We in-situ observe the ultrafast dynamics of trapped carriers in organic methyl ammonium lead halide perovskite thin films by ultrafast photocurrent spectroscopy with a sub-25 picosecond time resolution. Upon ultrafast laser excitation, trapped carriers follow a phonon assisted tunneling mechanism and a hopping transport mechanism along ultra-shallow to shallow trap states ranging from 1.72–11.51 millielectronvolts and is demonstrated by time-dependent and independent activation energies. Using temperature as an energetic ruler, we map trap states with ultra-high energy resolution down to < 0.01 millielectronvolt. In addition to carrier mobility of ~4 cm2V−1s−1 and lifetime of ~1 nanosecond, we validate the above transport mechanisms by highlighting trap state dynamics, including trapping rates, de-trapping rates and trap properties, such as trap density, trap levels, and capture-cross sections. In this work we establish a foundation for trap dynamics in high defect-tolerant perovskites with ultra-fast temporal and ultra-high energetic resolution.
KW - electronic properties and materials
KW - metal-halide perovskite
KW - semiconductors
KW - solar cells
KW - thin films
KW - transport
UR - http://www.scopus.com/inward/record.url?scp=85102385971&partnerID=8YFLogxK
U2 - 10.1038/s41467-021-21946-2
DO - 10.1038/s41467-021-21946-2
M3 - Article
C2 - 33712623
AN - SCOPUS:85102385971
SN - 2041-1723
VL - 12
JO - Nature Communications
JF - Nature Communications
IS - 1
M1 - Article No. 1636
ER -