The effect of Ln(3+) (Ln = Y, Nd) on the conductivity and gas-sensing properties of CdIn2O4 semiconductor

A series of Y- and Nd-doped samples Cd(1-x)Ln(x)In(2)O(4) (Ln = Y, Nd) were prepared by a chemical coprecipitation method. The phase constituents of t he samples were characterized by X-ray diffraction (XRD). The lattice const ant and particle size were calculated from XRD patterns of samples accordin g to a = d(h*2 + k(*2) + l(*2))(1/2) and Scherrer's equation. We investigat ed the effect of Ln(3+) on the microstructure, conductivity and gas-sensing properties of a CdIn2O4 semiconductor. The results revealed that a Y2O3 ph ase appears in doped samples when x > 0.30 and NdInO3 exists in materials w hen x greater than or equal to 0.15. The Ln dopants have very small effect on the lattice constant and particle size. The conductance of CdIn2O4 decre ases when doping it with Ln. However, Ln dopants enhance the sensitivity of CdIn2O4 to reducing gases, and a Cd0.9Nd0.1In2O4 based sensor exhibit good gas-sensing properties. (C) 2000 Elsevier Science S.A. All rights reserved .