Paper Title
Fine-Tuning Intermediate Band Width Using TB-MBJ Exchange Potential: Case Study With Β-INXVZSY Alloys

Abstract
Transition metals, especially vanadium plays a central role in intermediate band solar cells. Because V substituted indium in β-In2S3 matrix produces intermediate-band within the band gap of the β-In2S3. If the intermediate-band (IB) is half-filled, narrow and isolated from the valence and conduction band, then irradiative recombination is inhibited, and the efficiency of the solar cell is increased. The position of the IB in In7VS12 and In5.4VS9.6 is observed to be shifted when the modified Becke-Johnson (mBJ) potential is used. The IB width drops to about 0.22 eV for In7VS12 and rises to 0.06 eV in In5.4VS9.6 as compared to PBE-GGA calculations. The TB-mBJ calculated band structure along the direction of the BZ for In7VS12andIn5.4VS9.6 alloys clearly shows improvement in the position and width of the IB. Keywords- Solar cell; Intermediate-band width; Alloys; Vanadium; radiative recombination