Design and Simulation of a‐Si:H/PbS Colloidal Quantum Dots Monolithic Tandem Solar Cell for 12% Efficiency. Issue 20 (2nd September 2020)

• Record Type: Journal Article
• Authors: Kashyap, Savita; Pandey, Rahul; Madan, Jaya; Sharma, Rajnish
• Is Part Of: Physica status solidi. Volume 217:Issue 20(2020)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-09-02
• Subjects: a-Si:H -- monolithic tandem -- PbS colloidal quantum dots -- solar cells -- thin-films; Solid state physics -- Periodicals; Solids -- Industrial applications -- Periodicals; 530.41
• DOI: 10.1002/pssa.202000252
• Languages: English
• ISSNs: 1862-6300

Abstract

Abstract : Tandem solar cells (TSC) is the most promising photovoltaic technology, as it efficiently overcomes the thermalization and nonabsorption losses. In this context, thin‐film/colloidal quantum dot (CQD)‐based 2‐terminal monolithic TSCs are designed using a‐Si:H of wide bandgap (1.7 eV) as the top cell and PbS CQD of narrow bandgap (1.2 eV) as the bottom cell. Initially, top and bottom subcells are designed and calibrated to have state‐of‐the‐art power conversion efficiencies (PCE) of 6.86% and 9.38%, respectively. Afterward, the thicknesses of the inverted bottom cell are optimized as 200 nm so as to obtain 8.34% efficiency. The standalone condition reflects current density ( J SC )/open‐circuit voltage ( V OC ) of 9.97 mA cm −2 and 0.91 V in the top cell and 21.28 mA cm −2 /0.63 V in the bottom cell. Further, both subcells are evaluated for tandem configuration with ITO‐based interlayer to provide the current matching conditions. In the proposed tandem design, the thickness of the absorber layers is optimized to achieve the highest J SC, which is indeed limited by the top cell, due to a lower J SC value of 10.61 mA cm −2 in standalone conditions. Optimized tandem design with 200 nm/150 nm‐thick absorber layer‐based top/bottom subcell results in J SC of 10.52 mA cm −2, V OC of 1.59 V, FF of 71.65%, and PCE of 12.02%. Abstract : The design of 12.02% efficient a‐Si:H/PbS CQD‐based 2‐terminal monolithic tandem solar cells is brought forth herein. Tandem device under consideration exhibits photovoltaic parameters such as current density (10.52 mA cm −2 ), open‐circuit voltage (1.59 V), and fill factor (71.65%). Studies conducted for a Si:H/PbS CQD based 2 terminal monolithic tandem solar cell structures explore this field more deeply.