Performance Enhancement of Perovskite/Silicon Tandem Solar Cell Using Cu-Wire Interconnecting and CB-Doping

This study demonstrates that by utilizing Cu-wire interconnection and doping the active perovskite (PVSK) layer with 2 mg of carbon-based (CB) material, the conversion efficiency (η) of perovskite/silicon (PVSK/Si) tandem solar cells reaches 27.79%. Photoluminescence (PL), external quantum efficiency (EQE), and photovoltaic current-voltage under AM 1.5G illumination measurements were employed to characterize the performance of PVSK films and cells. The incorporation of CB into the PVSK light-absorbing layer enhances charge transport and reduces recombination losses, resulting in improved photovoltaic performance. Before interconnection, the PVSK cell exhibits an efficiency of η = 15.87%, with a short-circuit current density (Jsc) of 20.68 mA/cm<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup>, an open-circuit voltage (Voc) of 1.01 V, and a fill factor (FF) of 0.76. In comparison, the Si cell achieves an efficiency of η = 13.20%, Jsc = 37.31 mA/cm2, Voc = 0.59 V, and FF = 0.60. After interconnecting both cells, the PVSK/Si tandem cell demonstrates a notable performance boost, reaching η = 27.79%, Voc = 1.51 V, and FF = 0.89. This represents a 9.24% efficiency increase compared to the control tandem cell (η = 25.44%), which lacks CB doping. These findings highlight the potential of CB doping as a viable strategy for enhancing the efficiency of PVSK/Si tandem solar cells, paving the way for further advancements in next-generation photovoltaic technologies.