Computational Probing of Tin-Based Lead-Free Perovskite Solar Cells: Effects of Absorber Parameters and Various Electron Transport Layer Materials on Device Performance

Abstract

Tin-based perovskite solar cells have gained global research attention due to the lead toxicity and health risk associated with its lead-based analog. The promising opto-electrical properties of the Tin-based perovskite have attracted researchers to work on developing Tin-based perovskite solar cells with higher efficiencies comparable to lead-based analogs. Tin-based perovskites outperform lead-based ones in areas such as optimal band gap and carrier mobility. A detailed understanding of the effects of each parameter and working conditions on Tin-based perovskite is crucial in order to improve efficiency. In the present work, we have carried out a numerical simulation of a planar heterojunction Tin-based (CH3NH3SnI3) perovskite solar cell employing a SCAPS 1D simulator. Device parameters, namely, the thickness of the absorber layer, the defect density of the absorber layer, working temperature, series resistance, and metalwork function, were exclusively investigated. ZnO was employed as the ETL (electron transport layer) material in the initial simulation to obtain optimized parameters and attained a maximum efficiency of 19.62% with 1.1089 V open circuit potential (Voc) at 700 nm thickness (absorber layer). Further, different ETL materials were introduced into the optimized device architecture, and the Zn2SnO4-based device delivered an efficiency of 24.3% with a Voc of 1.1857 V. The obtained results indicate a strong possibility to model and construct better-performing perovskite solar cells based on Tin (Sn) with Zn2SnO4 as the ETL layer.

Studies of Performance of Cs2TiI6−XBrX (Where x = 0 to 6)-Based Mixed Halide Perovskite Solar Cell with CdS Electron Transport Layer

“…From Figure 2 c it is observed that the PCE increases with the higher metal work function of the Ag paste up to a certain work function value (5 eV). The reason behind such an increment in the work function value is the decrement of the height of the carrier barrier, and as a result, the metal contact becomes ohmic in nature [ 8 ]. Thus, open circuit voltages also increase.…”

“…As per the observations, the diffusion length increases with the open circuit voltage (V OC ) for all the seven absorbing materials except for Cs 2 TiI 5 Br 1 and Cs 2 TiI 6 , where the diffusion length decreases after 0.6 V. The concentrations of electrons and holes are enhanced with the voltage which leads to an increment in diffusion length. The diffusion length of the electrons and holes should be higher than the absorbing layer thickness [ 8 ], since Cs 2 TiBr 6 , Cs 2 TiI 1 Br 5 and Cs 2 TiI 6 absorbing materials have a band gap above 1.50 eV which requires large energy to excite an electron in the conduction band. Thus, such materials operate in a higher temperature which can burn the device after a certain temperature.…”

“…Titanium (Ti)-based PSCs were introduced by Ju et al 2018 with 1.0–1.8 eV tuneable band gap, and Chen et al (2018) achieved 1.02 V open circuit voltage (V OC , V), 5.69 mA/cm 2 current density (J SC , mA/cm 2 ) and 56.4% fill factor (FF, %) with Cs 2 TiBr 6 absorbing material [ 6 , 7 ]. Shyma et al 2022 employed SCAPS-1D-based simulation on Sn-based perovskite material CH 3 NH 3 SnI 3 to investigate the various parameters of the active materials and the selection of the appropriate ETL (electron transport layer) for the device [ 8 ]. On the other side, Omarova et al 2022 showed the selection of the optimal HTL (hole transport layer), and also determined that electrodes can minimize the effects of material defects to improve the device performance [ 9 ].…”

A Numerical Approach to Analysis of an Environment-Friendly Sn-Based Perovskite Solar Cell with SnO2 Buffer Layer Using SCAPS-1D

“…In 2019, the work had a conversion efciency of 23.76% [17]. For the proposed (Zn 2 SnO 4 / CH 3 NH 3 SnI 3 /Spiro-MeOTAD) structure, the obtained conversion efciency in 2021 is 24.73% [18]. In 2017, it had a conversion efciency of 24.82%, J SC of 25.67 mA/cm 2 , FF of 78.14% and V OC of 1.0413 V [19].…”

Experimental and computational DFT, drift-diffusion studies of cobalt-based hybrid perovskite crystals as absorbers in perovskite solar cells

“…Drift-diffusion modelling can be utilised for this purpose. 21–24 Material properties such as band structure, Eigen states, and the electron-density profile can be analysed by Device Studio software with a “nanodcal” package. Addition of Fe and Ni to DMACF can improve the bandgap of the material (an essential factor for solar-cell efficiency).…”