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

Abstract

This paper introduces a novel tandem configuration, utilizing an all-thin film all-polymer solar cell (all-PSC) with a wide bandgap of 1.76 eV for the front cell and Sb2Se3 with a narrow bandgap of 1.2 eV for the bottom cell. The design of this tandem is performed by comprehensive optoelectronic TCAD tools, essential for optimizing parameters across multiple layers to reach maximum power conversion efficiency (PCE). Experimental validation of models is conducted through calibration and validation against fabricated reference all-polymer and Sb2Se3 solar cells, yielding calibrated PCEs of approximately 10.1% and 10.5%, respectively. Subsequently, validated simulation models for both top and rear cells are utilized to design a 2-T all-polymer/Sb2Se3 tandem cell, which initially achieves a PCE of 10.91%. Through systematic optimization steps, including interface engineering and homojunction structure design, a remarkable PCE of 24.24% is achieved at the current matching point, showcasing the potential of our proposed tandem solar cell design. This study represents a significant advancement in the field of thin-film tandem solar cells, offering promising avenues for efficient and cost-effective photovoltaic technologies, particularly in applications requiring flexibility.

TCAD-Based Design and Optimization of Flexible Organic/Si Tandem Solar Cells

“…The defect parameters of the OSC have been meticulously adjusted to achieve the best possible fit between the simulation results and the measured data. The obtained fitting values, listed in Table S3, are in agreement with other similar studies [9,42,46]. Additionally, the quantitative cell parameters of the simulated and experimental OSC and Si cells are detailed in Table 1.…”

“…The physical models implemented in Atlas have been validated through extensive experiments for single and tandem solar cells [42][43][44]. The calculated results presented in this study are supported by experimental data.…”

“…The following supporting information can be downloaded at: https://www.mdpi.com/article/10.3390/cryst14070584/s1, Figure S1: Absorption coefficients deduced from available experimental data for the bottom Si cell: (a) c-Si [54] and (b) a-Si layers [55]; Figure S2: Absorption spectrum of (a) PBDB-TCl:AITC absorber layer [34], (b) UV-vis absorption spectrum of PNDIT-F3N-Br layer [45], (c) Real, and (d) imaginary refractive index Refractive indices deduced from available experimental data for PEDOT:PSS layer [56]; Figure S3: (a) Illuminated J-V curves, and (b) EQE spectra of TSC and its cells, coupled using a tunnel junction; Figure S4: Efficiency over time for various tandem solar cell configurations from 2020 to 2024; Table S1: Definition of physical quantities used in Atlas device simulator; Table S2: Main parameters of various layers of organic solar cell [34,45,57]; Table S3: Defect parameters in OSC; Table S4: Main factors of various layers of thin Si cell [4,38,50,58]; Table S5: A state-of-the-art comparison between tandem cell metrics for a wide range of tandem systems [4,6,7,9,36,42,50,52,53,[59][60][61][62][63][64][65][66][67][68]…”

Comprehensive design and analysis of thin film Sb2S3/CIGS tandem solar cell: TCAD simulation approach

“…In the ray tracing model, the optical intensity is assessed using the real refractive indices, whereas in the photogeneration model, the absorption coefficients are utilized to determine the carrier densities. Unlike 1D simulators such as SCAPS, Silvaco offers a more comprehensive approach by simulating the entire tandem structure and providing detailed optical generation rates directly [22,39]. In contrast, SCAPS adopts a different strategy, solving for the top sub-cell first and then extracting the filtered spectrum from the top sub-cell to be inputted into the bottom sub-cell [40,41].…”