Performance enhancement of Sb2Se3-based solar cell with hybrid buffer layer and MoSe2 as a hole transport material using simulator device

Abstract

In this work, we first compared the experimental and simulated J-V characteristics of the Sb2Se3-based solar cell without and with a hybrid buffer layer using SCAPS-1D software. The introduction of a second buffer layer reduces the current leakage caused at the front contact of the solar cell and the power conversion efficiency (PCE) increases from 3.75% to 5.18%; and the use of the ternary compound cadmium zinc sulfide (CdZnS), as an alternative electron transport layer (ETL) to the traditional cadmium sulfide (CdS), increases the PCE from 5.18% to 7.13%. Thereafter, different thicknesses of the SnO2/CdZnS hybrid buffer layer were simulated, and the optimization resulted in a value of 50 nm, with thicknesses of 10 nm and 40 nm for the SnO2 and CdZnS layers respectively. Furthermore, the optimization of the Sb2Se3 absorber allows to obtain a bulk defect density of 1011 cm−3 and a carrier capture cross section of 10–14 cm2. Finally, the low doping problem of the absorber is solved by forming a MoSe2 layer at the Sb2Se3/Mo interface. MoSe2 acts as a hole transport material (HTM) and is used for high mobility of charge carriers within it; moreover, its presence improves the performance of the Sb2Se3-based solar cell and a PCE of 18.77% (JSC = 34.37 mA/cm2, VOC = 660 mV, FF = 82.78%) is obtained. Our simulation results also show that the n-i-p configuration of the Sb2Se3-based solar cell is more stable.