An experimental and theoretical study into NaSbS2 as an emerging solar absorber

As photovoltaics have grown to become one of the dominant renewable energy generating technologies, attention has fallen upon thin-film materials as a route to lightweight, flexible and portable solar cells. NaSbS 2 has recently been proposed as a non-toxic, earth abundant solar absorber for thin-film cells. In this study, we use a combined theoretical and experimental approach to characterize and assess the electronic and optical properties of NaSbS 2 as an emerging solar absorber. Our results, utilising two theoretical efficiency metrics, demonstrate that NaSbS 2 may be limited for use in single-junction cells by a forbidden band gap and slow absorption onset. Other features of its electronic structure, however, indicate that the material may still be promising in thermoelectric applications. NaSbS 2 has recently been proposed as an emerging solar cell material, however in this study we demonstrate that it may be limited by a forbidden band gap, and instead possesses a more suitable electronic structure for thermoelectrics.