From the past couple of years, the high-power conversion efficiency (PCE) of >25% and low-cost fabrication of single-junction perovskite photovoltaic cells have gained great attention from researchers. The bandgap tunability of these solar cells makes them an attractive and ideal candidate for tandem solar cell applications. The PCEs above than the single-junction solar cells theoretical Shockley-Queisser (SQ) radiative efficiency limit (31%-33%) can be achieved by harvesting a wide fraction of solar spectrum using multi-junction solar cells. In perovskite tandem (double-junction) solar cells, a wide-bandgap perovskite top cell is combined with either narrow-bandgap bottom cells of dissimilar materials like silicon (Si) and copper indium gallium selenide (CIGS) or with low bandgap perovskite solar cell. In this work, we have simulated perovskite/Si (PVK/Si), perovskite/CIGS (PVK/CIGS) and perovskite/perovskite (PVK/PVK) tandem solar cells and estimated 28.73%, 20.31% and 26.06% PCEs. The highest conversion efficiency is shown by PVK/Si tandem cells among others because of the suitable bandgap for tandem applications. Our work will guide the researchers for obtaining ultra-high conversion efficiency solar cells.
Saddam Hussain and Adnan Daud Khan Device Modeling and Numerical Characterization of Perovskite/Si Perovskite/CIGS and all-Perovskit
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