p-Type Iodine-Doping of Cu3N and Its Conversion to γ-CuI for the Fabrication of γ-CuI/Cu3N p-n Heterojunctions

Cu3N with a cubic crystal structure is obtained in this paper by the sputtering of Cu under N2 followed annealing NH3: H2 at 400 °C, after which it was doped iodine room temperature resulting into p-type hole densities between 1016 and 1017 cm−3. The exhibited distinct maxima differential transmission ~2.01 eV 1.87 as shown ultrafast pump-probe spectroscopy, corresponding to M R direct energy band gaps excellent agreement density functional theory calculations, suggesting that gap clean free mid-gap states. gradually converted optically transparent γ-CuI had 4 × cm−3, mobility 12 cm2/Vs photoluminescence 3.1 its gap. We describe fabrication properties γ-CuI/TiO2/Cu3N γ-CuI/Cu3N p-n heterojunctions rectifying current-voltage characteristics, but no photogenerated current attributed indirect recombination via shallow states and/or deep consistent short (ps) lifetimes photoexcited electrons-holes determined from transient absorption–transmission spectroscopy.