Double-Absorber CZTS/Sb2Se3 Architecture for High-Efficiency Solar-Cell Devices

The design and configuration of solar cells are critical for photovoltaic action and achieving high efficiency. Herein, the double-absorber solar-cell architecture of low-bandgap Sb2Se3 and high-bandgap Cu2ZnSnS4 (CZTS) absorbers for broader spectrum utilization leading to higher efficiency are comprehensively analyzed. The cost-effective chalcogenides CZTS and Sb2Se3 for high-efficiency dual-absorber configuration to show the possibility of high wattage at a lower cost are taken. The crucial parameters of bandgap pair and thickness are optimized for synergetic device performance and optimal utilization of the incident spectrum. By introducing an additional absorber-absorber interface, the interfacial defect at CZTS/Sb2Se3 is lowered by optimizing the band offset for the efficient functioning of a double-absorber device. The proposed device has straightforward NiO/CZTS/Sb2Se3/AZO architecture suitable for low-cost fabrication with high efficiency of 30.9%.