Effect of heat treatment under sulfur atmosphere on physical properties of pyrite (FeS2) sprayed thin films

摘要

This paper aims to investigate the structural, optical and electrical characteristics of the pyrite films FeS2 grown by a spray pyrolysis method at low substrate temperature 250 degrees C followed by a heat treatment at various temperatures. The effect of annealing temperature on film properties was discussed. X-ray diffraction revealed that all annealed films were polycrystalline with cubic structure. The direct band gap energy deceases from 1.51 to 1.26 eV with increasing of the annealing temperature. On the other hand, the electrical investigation shows FeS2 has p-type conductivity and the electrical conductivity measurements lead to a power Jonscher low. The dependence of conductivity in alternative current sAC with temperature and frequency agrees well with the single-polaron hopping model, SBH model. (C) 2016 Elsevier B.V. All rights reserved.