Device engineering of Sb₂X₃ antimony chalcogenide for loss analysis and strategies for maximizing photovoltaic efficiency

Abstract

Antimony chalcogenide (Sb2X3; X=S, Se) is reportedly stable in ambient open-air, abundant, and composition-dependent absorption tunability. We simulated the Sb2X3 device utilizing the reported optical and electrical properties to analyze its reported efficiency critically and the extent of achievable performance. Initially, we benchmarked the simulated device with the experimental reported device. The temperature-VOC, illumination-VOC characterization of the benchmarked device revealed contact issue responsible for the VOC deficit. The suboptimal device configuration is major performance-limiting factor. Contact optimization improved efficiency to 15% and 20% in Sb2S3 and Sb2Se3, respectively. The optimization of trap-assisted Shockley Read Hall (SRH) recombination in bulk and interface has improved efficiency to 19% and 26% in Sb2S3 and Sb2Se3, respectively. When extrinsic factors are optimised, such as resistance losses (series resistance as high as 2 Ωcm2 and shunt resistance as low as 1000 Ωcm2), efficiency increased to 27.5%. Finally, with ideal intrinsic recombination parameters (radiative and Auger recombination), efficiency improved to theoretical limits (corresponding to their band gap). The study highlights the possibility of immediate gain upon contact passivation in Sb2S3 and Sb2Se3.

The role of interface energetics in Sb2Se3 thin film solar cells

“…SCAPS is a well-established software package in the photovoltaic (PV) community, offering extensive simulation capabilities for various experimental observations. These include simulating impurity photovoltaic effects, tandem structures, bandgap grading, light soaking behaviour, J-V hysteresis, etc [13][14][15][16][17][18][19].…”

“…Material/device parameters and simulation condition as utilised to study interface energetics in thin film solar cells. [1,13,14,20,21].…”

“…Absorber (p) Sb 2 Se 3 [1,14] Buffer (n) (CdS) [13,20] Window (n + ) (ZnO) [21] Window (n ++ ) (AZO) [21] Thickness EV is valence band level, Et is defect energy level. and output fill factor and is the main contributor to trap-assisted Shockley-Read-Hall (SRH) recombination and non-radiative losses in operational devices.…”