Design of n-i-p and p-i-n Sb₂Se₃ solar cells: role of band alignment

Abstract

Investigations into novel device architectures and interfaces that enhance charge transport and collection are necessary to increase the power conversion efficiency (PCE) of antimony selenide (Sb2Se3) solar cells, which have shown great promise as a low-cost and high-efficiency alternative to conventional silicon-based solar cells. The current work uses device simulations to design p-i-n and n-i-p Sb2Se3-based solar cell structures. The n-i-p configuration is investigated by comparing distinct electron transport layer (ETL) materials to get the best performance. While certain ETL materials may yield higher efficiencies, the J–V curve may exhibit S-shaped behavior if there is a misalignment of the bands at the ETL/absorber interface. To address this issue, a proposed double ETL structure is introduced to achieve proper band alignment and conduction band offset for electron transport. A PCE of 20.15% was achieved utilizing (ZnO/ZnSe) as a double ETL and Spiro-OMeTAD as a hole transport layer (HTL). Further, the p-i-n configuration is designed by proposing a double HTL structure to facilitate hole transport and achieve a proper valence band offset. A double HTL consisting of (CuI/CuSCN) is used in conjunction with ETL-free configuration to achieve a PCE of 21.72%. The simulation study is conducted using the SCAPS-1D device simulator and is validated versus a previously fabricated cell based on the configuration FTO/CdS/Sb2Se3/Spiro-OMeTAD/Au.

Optimizing Transport Carrier Free All-Polymer Solar Cells for Indoor Applications: TCAD Simulation under White LED Illumination

“…Additionally, SCAPS offers flexibility in parameter adjustment. This facilitates the simulation of various operating conditions and assesses the robustness of indoor solar cell designs [30].…”

“…Furthermore, the establishment of an appropriate band alignment between the ETL and the electrode is essential to maintain a continuous and unimpeded flow of charge carriers toward the electrode. Additionally, the selection and engineering of ETL materials and their properties, such as electron mobility and conductivity, significantly impact the charge transport dynamics within the device [30,43]. By optimizing the choice of ETL materials, it is possible to enhance electron transport efficiency and minimize recombination losses, ultimately leading to improved device performance and higher solar cell efficiency.…”

Optimization of all-polymer/Sb2Se3 tandem solar cells for enhanced efficiency: a comprehensive TCAD modeling approach

“…Moreover, there exists a notable gap in the exploration of alternative materials, particularly those with potential cost and sustainability advantages. In comparison to Si and perovskite tandems, Sb 2 Se 3 -based tandems hold the promise of lower production costs and improved environmental sustainability, owing to the abundance and eco-friendliness of the constituent materials [29,37]. Additionally, compatibility with flexible substrates, position it as a competitive candidate for tandem configurations.…”