CsPbI
3
has recently received tremendous attention as
a possible absorber of perovskite solar cells (PSCs). However, CsPbI
3
-based PSCs have yet to achieve the high performance of the
hybrid PSCs. In this work, we performed a density functional theory
(DFT) study using the Cambridge Serial Total Energy Package (CASTEP)
code for the cubic CsPbI
3
absorber to compare and evaluate
its structural, electronic, and optical properties. The calculated
electronic band gap (
E
g
) using the GGA-PBE
approach of CASTEP was 1.483 eV for this CsPbI
3
absorber.
Moreover, the computed density of states (DOS) exhibited the dominant
contribution from the Pb-5d orbital, and most charges also accumulated
for the Pb atom as seen from the electronic charge density map. Fermi
surface calculation showed multiband character, and optical properties
were computed to investigate the optical response of CsPbI
3
. Furthermore, we used IGZO, SnO
2
, WS
2
, CeO
2
, PCBM, TiO
2
, ZnO, and C
60
as the electron
transport layers (ETLs) and Cu
2
O, CuSCN, CuSbS
2
, Spiro-MeOTAD, V
2
O
5
, CBTS, CFTS, P3HT, PEDOT:PSS,
NiO, CuO, and CuI as the hole transport layers (HTLs) to identify
the best HTL/CsPbI
3
/ETL combinations using the SCAPS-1D
solar cell simulation software. Among 96 device structures, the best-optimized
device structure, ITO/TiO
2
/CsPbI
3
/CBTS/Au, was
identified, which exhibited an efficiency of 17.9%. The effect of
the absorber and ETL thickness, series resistance, shunt resistance,
and operating temperature was also evaluated for the six best devices
along with their corresponding generation rate, recombination rate,
capacitance–voltage, current density–voltage, and quantum
efficiency characteristics. The obtained results from SCAPS-1D were
also compared with wxAMPS simulation results.
