P-type transition metal carbodiimides MNCN (M = Ni, Mn)

International audienceOver the last decade, p-type semiconductors (SC) have known a renewed interest. Indeed these materials may have potential applications for light-emitting diodes, transistors, solar cells, etc. Since the stabilization of the first p-type semiconductor CuAlO2 with a delafossite structure type (A+B3+O2) by H. Kawazoe in 1997, many p-type semiconductors with the same structure have been reported such as CuGaO2, CuCrO2, CuScO2… Recently, X. Liu & al have reported the synthesis and the structure determination of a new family of materials: the transition metal carbodiimides MNCN (with M = Mn → Cu). These materials adopt a structure type related to the delafossite, formed by a divalent transition metal and NCN2-anion. We report here the synthesis and the microstructural characterization of two transition metal carbodiimides MnNCN and NiNCN. Impedance measurements demonstrate the p-type conductivity of these materials.