Evaluation of Ni doping for promoting favorable electronic structures in CuCrO2 and AgCrO2 from a first-principles perspective

Doping transparent conducting oxides in the delafossite form with Ni has been presented in the literature as an exciting candidate to improving the conductivity while maintaining the transparency of these materials. Here, the effects of 6.25% Ni doping on the electronic, structural, and hole effective masses in the 2H phase of XCrO2 (X = Cu, Ag) is studied using spin polarized ab initio calculations. 6.25% Ni doping is found to produce an asymmetry across spin in both materials, as well as decrease the bandgaps, potentially harming transparent character. Hole effective masses are calculated to be heavier in every lattice vector direction for CuCrO2, but in AgCrO2 hole effective masses are lighter overall. Considering that 6.25% Ni doping introduces an increase in hole concentration, AgCr0.94Ni0.06O2 should have a higher conductivity as result of 6.25% Ni doping, while the same doping may reduce the conductivity of CrCr0.94Ni0.06O2.