Cuprous oxide type conduction

Copper(I) oxide [1317-39-1] is 2lp-ty e semiconductor, Cu2 0, in which proper vacancies act as acceptors to create electron holes that conduct within a narrow band in the Cu i7-orbitals. Nickel monoxide [1313-99-17, NiO, forms a deficient semiconductor in which vacancies occur in cation sites similar to those for cuprous oxide. For each cation vacancy two electron holes must be formed, the latter assumed to be associated with regular cations ([Ni " h = Semiconduction results from the transfer of positive charges from cation to cation through the lattice. Conduction of this type is similar... 

Common p-type conductivity is rather rare for oxides formed in ligand-containing solutions such cuprous oxide developed in the solutions containing ethylenediamine, which can act as a reductant. More often -Cu20 species are formed, as in weakly acid solutions containing such ligands as amino or hydroxy acids. It was found that the type of conductivity can alter during the development of oxide layer. Then the transition from p-type (thin initial layers) to n-type conductivity (thicker layers) is observed. 

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