Physio-chemical modification of CuSCN by lanthanum dopant towards improving hole transport mechanism for perovskite solar cell applications

Copper(I) thiocyanate (CuSCN) is gaining attention as an effective hole transport layer (HTL) in perovskite solar cells (PSCs) due to its excellent electronic properties, high stability, and superior hole mobility. Unlike the commonly used HTL Spiro-OMeTAD, which is sensitive to moisture and degrades quickly, CuSCN offers enhanced moisture resistance and improved durability without compromising efficiency. However, its low hole concentration and conductivity limit its performance. This study investigates the doping of CuSCN with lanthanum (La) to overcome these challenges. La doping introduces additional charge carriers, significantly increasing conductivity. Using dimethyl sulfoxide (DMSO) as a solvent for solution processing, we achieved a highly transparent and stable CuSCN HTL. The optimal La doping concentration was found to be 3 mol%, yielding a conductivity of 4.13 S cm-1 and a band gap of 3.67 eV. SCAPS-1D simulation analysis was further employed to optimize the CuSCN HTL thickness, identifying 100 nm as the ideal thickness to maximize device performance. With this thickness optimization, the power conversion efficiency (PCE) improved from 28.17% for pristine CuSCN to 30.54% with 3 mol% La doping. These results demonstrate that tailored La doping combined with optimized HTL thickness can effectively enhance CuSCN's properties, offering a promising route for developing high-performance and durable PSCs.

Journal

PHYSICA SCRIPTA

Year

2025

Volume

100

Issue

11

ISSN

0031-8949

eISSN

1402-4896

DOI

10.1088/1402-4896/ae176b

WoS UID

WOS:001613388300001