Theoretical analysis of electronic, optical, photovoltaic and thermoelectric properties of AgBiS2.

The present work aims at investigating the electronic, optical, photovoltaic and thermoelectric properties of AgBiS 2 compound using the density functional theory (DFT) and the modified Becke-Johnson exchange-correlation potential (mBJ). Both hexagonal Matildite and cubic Schapbachite polymorphs were considered. The hexagonal phase is found to be indirect gap semiconductor with band gap energy of about 1.07 eV and high absorption coefficient of 106 cm−1, whereas the cubic phase were metallic. The analysis of band alignment of Matildite with some binary oxides and sulfides revealed interesting results. The photovoltaic properties of AgBiS 2 confirmed that Matildite phase could achieve a short-circuit current of 22 mA/cm2 and conversion efficiency of 20%. Also, we demonstrated that including photon recycling with a proper solar cell design could improve the conversion efficiency. Moreover, interesting thermoelectric performance has been confirmed. • Detailed ab initio investigation of AgBiS 2 polymorphs is presented. • AgBiS 2 semiconducting phase exhibit interesting electronic and optical properties. • Band alignment at interfaces with binary compounds (oxides and sulfides) is addressed. • High short-circuit current and SLME are achieved for Matildite AgBiS 2. • AgBiS 2 polymorphs exhibit interesting thermoelectric performance. [ABSTRACT FROM AUTHOR]