Study on the electronic properties of In2O3 doped with Eu3+: a first principle calculation

As an n-type wide band gap nanomaterial (2.7-2.9 eV), In2O3 has an important application in gas sensing, light-emitting diodes, semiconductor lasers, medical imaging and other fields. Research shows that the luminous efficiency of In2O3 can be improved through rare earth doping. Eu3+, Er3+ doping has been widely studied, but there is no relevant explanation for the transition mechanism. In this paper, the formation energy of Eu3+ doped in different site as a functional of temperature and electronic properties was calculated by using first principal calculations. The result showed that under O-rich conditions, the formation energy is negative below 500 K regardless of the doping site, which proves that rare earth atoms below 500 K are very easy to be doped, especially Eu3+ at the In1(3) (or In1) site and the Eu3+ doped decrease the band gap. Then the best synthesis conditions are found to determine the doping site, which provides a theoretical basis for the experiment. At the same time, considering the experimental conditions oxygen vacancy (VO) also exist, we calculated the band structure of the In2O3 with VO and Eu3+ doped. It provides a basis for in-depth analysis of the function of impurity energy levels formed after rare earth element doping in the experiment from the matrix to the luminous center.