N-type doping feasibility of Cu2O with In and Al for cost-effective photovoltaics: An ab initio investigation

The present work deals with the first principle calculations under the framework of density functional theory to realize n-type conductivity in Cu2O by doping it with practically feasible dopants: In and Al. From the electronic density of states and band structure calculations, it was found that both In and Al create deep level donor states at 0.84 eV and 1.32 eV respectively above the valence band maximum. The optical band gap was found to be widened from 2.04 eV for pure Cu 2 0 to 2.66 eV and 3.05 eV for In and Al doping respectively. The optical absorption coefficient was found to be similar to 10(6) m(-1) for pure Cu2O and similar to 10(7) m(-1) for the doped systems. The charged defect formation energy calculation shows that both these cationic substitutional defects are thermodynamically more favourable under Cu rich conditions.

Automated summary

This study uses density functional theory to investigate the realization of n-type conductivity in Cu2O by doping it with In and Al. The dopants create deep donor states above the valence band maximum, resulting in widened optical band gaps and increased optical absorption coefficients in the doped systems. Moreover, the cationic substitutional defects of In and Al are thermodynamically more favorable under Cu rich conditions.