Identifying the potentials for charge transport layers free n-p homojunction-based perovskite solar cells

• Published in: Solar energy 2022-05, Vol.238, p.69-77
• Main Authors: Khan, Danish, Sajid, Sajid, Khan, Suliman, Park, Jongee, Ullah, Ihsan
• Format: Article
• Language: English
• Subjects: Acceptor density; Capacitance; Charge transport; Computer architecture; CTLs-free PSC; Current carriers; Defect density; Density; Electrodes; Energy conversion efficiency; Fabrication; Homojunctions; Metal concentrations; P-type absorber; Perovskites; Photovoltaic cells; Solar cells; Solar energy; Thickness; Work function
• ISSN: 0038-092X; 1471-1257
• DOI: 10.1016/j.solener.2022.04.034

[Display omitted] •Based on n-p homojunction, a novel CTLs-free PSC is designed.•Critical parameters that can influence device performance are examined and modified.•In the CTLs-free PSC, an efficiency of 15.6% is obtained under optimal conditions. Perovskite solar cells (PSCs) with no charge transport layers (CTLs) could be one of the major device architectures for the production of simple and low-cost devices. However, CTLs-free PSCs based on n-p homojunction have yet to show high power conversion efficiency (PCE), which is most likely due to inadequate light-and charge-management in the p-type perovskite. The device operation is examined using Solar Cell Capacitance Simulator (SCAPS)-software, and a novel n-p homojunction design is proposed to attempt efficient CTLs-free PSCs. Several aspects of p-type layer that can affect device performance, such as acceptor density, photon-harvesting capability, defects density, and resistances to the transport of charge-carriers are scrutinized and adjusted. Furthermore, the effects of different work-functions of metal electrodes are examined. A suitable acceptor concentration is required for oriented charge transport. It is determined that a p-type perovskite with a thickness of 0.3 μm is advantageous for high performance. A metal electrode with a high work-function is essential for efficient device. Consequently, a PCE of 15.60% is obtained with an optimal defect density of E15 cm−3, indicating that n-p homojunction-based CTLs-free PSCs are promising since they simplify the device design and fabrication process while retaining an acceptable PCE.