Synthesis and characterisation of (Fe2−xNi1·5x)O3 semiconductor nanoparticles

Abstract

(Fe2−xNi1·5x)O3 semiconductor nanoparticles were prepared by an improved homogenous coprecipitation method using analytical pure FeCl3.3H2O and NH3.H2O as main reagents under different molar ratios n(Ni2+)/n(Fe3+). It was found that the (Fe2−xNi1·5x)O3 particles with a mean particle dimension of ∼50 nm have a corundum type crystal structure. The substitution of Fe3+ ion by Ni2+ leads to the change of the lattice parameters. The lattice parameters a and b increase greatly, while c does not increase, with increasing Ni doping. In addition, the Ni2+ doping brings on impurity defects and the formation of an acceptor level in the crystal structure of Fe2O3, which leads to the increase in crystal grain growth energy, the decrease in crystallite size and the increase in electric conductivity. Non-noble element doped nano-Fe2O3 with good semiconductor performance is promising for applications where pure nano-Fe2O3 cannot be used; moreover, it has the potential to replace high cost, high environmental impact, noble element doped nano-Fe2O3.