Structural, Electronic, and Optical Properties of N-doped SnO2
Structural, electronic, and optical properties of various N-doped SnO2 were investigated using firstprinciples calculations. The calculated formation energies show that both the substitutional and the interstitial N atoms are preferentially occupied in anion sites, while the N defect formation energies in the O-rich conditions are much lower than that in the Sn-rich ones. The electronic structures demonstrate that three mechanisms are possible with regard to the red-shift of photoluminescence. The first is that the band gap width reduces because of N2p repulsing O2p states and raising up the top of valence band (EV) with N substituting for Sn; the second is that some N2p gap states are induced by N substituting for O resulting in the band gap reducing; and the third is N2p states lowering the bottom of the conduction band (EC) leading to the reduction of band gap by introducing a interstitial N. On the basis of the calculated formation energy and experimental results, the red-shift phenomenon should not be the transition from band to band but the band to gap states. The red-shift mechanism should be N2p gap states to band transition.
Xueqin Sun Run Long Xiufeng Cheng Xian Zhao Ying Dai Baibiao Huang
State Key Laboratory of Crystal Materials School of Physics, Shandong University, Jinan 250100, Peoples Republic of China
国际会议
武汉
英文
106-109
2010-09-01（万方平台首次上网日期，不代表论文的发表时间）