Investigating the potential of earth-abundant ZnSnxGe1-xN2 alloys for quantum well solar cells

Abstract

Zinc Tin Germanium Nitride (ZnSnxGe1-xN2) alloys, which consist of the ternary nitrides ZnSnN2 and ZnGeN2, are notable for being earth-abundant materials that offer numerous advantages over III-V materials in the fields of solar energy conversion and light emission. These benefits include adjustable bandgaps, high absorption coefficients, lower toxicity profiles, and compatibility with silicon-based technology. Developing highly efficient and sustainable photovoltaic (PV) technologies remains crucial in meeting our changing energy needs. In this pursuit, II-IV-V2 compounds and perovskites have recently emerged as promising materials for advancing solar energy conversion. This paper aims to enhance the performance of ZnSnxGe1-xN2/GaN multi-quantum well (MQW) solar cells by conducting thorough simulation and analysis. It explores the effect of different factors, like tin concentration, the number of quantum wells or periods, and operating temperature, on the electrical properties of the PV cell. These characteristics comprise current-voltage (J-V), power-voltage (P–V), and quantum efficiency (QE). Furthermore, vital parameters necessary for all analyses, including strain, critical thickness, absorption coefficients, electric field, and photo-generation rate, have been extensively examined. The research findings presented in this study show that a PV device made up of 50 quantum wells with a tin concentration of 60 % at a temperature of 300K results in considerably improved PV parameters: JSC = 9.23 mA/cm2, VOC = 1.87 V, FF = 73.29 %, and PCE = 12.62 %. These results highlight the significant potential of ZnSnxGe1-xN2/GaN multi-quantum well solar cells as a crucial step towards achieving a more sustainable and efficient energy future. In summary, combining ZnSnxGe1-xN2 alloys with III-N materials presents a promising opportunity to enhance the efficiency and stability of photovoltaic devices. This contributes to the continuous advancement of renewable energy solutions.