[Paper Review] Integrating transfer matrix method into SCAPS-1D for addressing optical losses and per-layer optical properties in perovskite/Silicon tandem solar cells

Peymaneh Rafieipour, Aminreza Mohandes+2 more|arXiv (Cornell University)|Aug 2, 2023

Perovskite Materials and Applications4 citations

TL;DR

This paper integrates the transfer matrix (TM) method into SCAPS-1D to accurately model per-layer optical losses and improve photovoltaic performance in perovskite/silicon tandem solar cells. By replacing the conventional Beer-Lambert method, the TM approach reduces overestimation of efficiency by ~4% and enables optimization of the recombination junction (RJ) layer, increasing device efficiency from 19.81% to 23.10% with an ITO ad-layer.

ABSTRACT

SCAPS-1D software ignores optical losses and recombination junction (RJ) layer in studying tandem solar cells (TSCs). This paper presents an optoelectronic study of a perovskite/Silicon TSC, comparing the effects of using two different methods of calculating filtered spectra on the photovoltaic performance parameters of tandem device. It is shown that integrating transfer matrix (TM) method into SCAPS-1D addresses per-layer optical losses and provides a platform for optimizing the RJ layer in TSCs. Using Beer-Lambert (BL) method for calculating the filtered spectra transmitted from the perovskite top sub-cell is revealed to overestimate the cell efficiency by ~4%, due to its inability to fully address optical losses. Also, the BL method fails to tackle any issues regarding optical improvement through ITO ad-layer on the RJ. Using TM formalism, the efficiency of the proposed perovskite/Silicon TSC is shown to be increased from 19.81% to 23.10%, by introducing the ITO ad-layer on the RJ. It is the first time that the effect of filtered spectrum calculation method is clearly investigated in simulating TSCs with SCAPS-1D. The results pave the way to introduce the optical loss effects in SCAPS-1D and demonstrate that the BL method that has been used before needs to be revised.

Motivation & Objective

• To address the long-standing omission of optical losses and per-layer optical properties in SCAPS-1D simulations of tandem solar cells.
• To evaluate the impact of different filtered spectrum calculation methods—specifically Beer-Lambert (BL) versus transfer matrix (TM)—on photovoltaic performance metrics.
• To demonstrate the feasibility and benefits of integrating the TM method into SCAPS-1D for accurate modeling of optical phenomena in perovskite/silicon tandem devices.
• To investigate the role of the ITO ad-layer on the recombination junction in enhancing optical transmission and overall device efficiency.

Proposed method

• The transfer matrix (TM) method is implemented into SCAPS-1D to model the optical transmission, reflection, and absorption across each layer of the perovskite/silicon tandem solar cell structure.
• The TM formalism accounts for interference effects and layer-specific optical properties, enabling precise calculation of filtered spectra through the device stack.
• The Beer-Lambert (BL) method is used as a baseline for comparison, which assumes exponential attenuation without considering interference or multilayer optical coupling.
• The simulation framework is applied to a standard perovskite/silicon tandem cell with a recombination junction (RJ) layer, including an ITO ad-layer for optical enhancement.
• Optical parameters such as refractive index and extinction coefficient are assigned to each layer based on experimental data or literature values.
• Photovoltaic performance metrics—such as Jsc, Voc, FF, and efficiency—are extracted and compared between the BL and TM methods.

Experimental results

Research questions

• RQ1 How does the choice of filtered spectrum calculation method (Beer-Lambert vs. transfer matrix) affect the simulated efficiency of perovskite/silicon tandem solar cells in SCAPS-1D?
• RQ2 To what extent does the BL method overestimate device efficiency due to its failure to model optical losses accurately?
• RQ3 Can the integration of the TM method into SCAPS-1D enable effective optimization of the recombination junction layer for improved optical transmission?
• RQ4 What is the impact of adding an ITO ad-layer on the recombination junction on the overall optical and electrical performance of the tandem cell?
• RQ5 Does the TM-based simulation reveal previously unaccounted optical losses that significantly affect device performance?

Key findings

• The Beer-Lambert method overestimates the tandem cell efficiency by approximately 4% due to its inability to model interference and per-layer optical losses accurately.
• The transfer matrix method reveals that optical losses in the perovskite top cell and recombination junction are substantial and previously underestimated in SCAPS-1D simulations.
• Introducing an ITO ad-layer on the recombination junction increases the device efficiency from 19.81% to 23.10% when using the TM method, demonstrating the importance of precise optical modeling.
• The TM method enables accurate assessment of optical improvements from nanostructured or doped layers, such as ITO, which the BL method fails to capture.
• This study establishes the first direct comparison of BL and TM methods in SCAPS-1D for tandem solar cells, proving that the BL method must be revised for reliable simulation.
• The integration of the TM method into SCAPS-1D provides a robust platform for optimizing optical design in perovskite/silicon tandem solar cells.