First-principles study of nitrogen-doped CuAlO2

► We calculate the electronic structure and formation energies of N-doped CuAlO2 using first-principles calculations. ► The N atom prefers to substitute an O atom rather than to occupy an interstitial site. ► The NO acts as a shallow accepter while the Ni acts as a deep accepter. ► After N doping, the fundamental band gap remains unchanged.