摘要
The electronic structure characters are calculated for the Zn1-∞MxO alloys with some Zn atoms in ZnO substituted by 3d transition-metal atoms (M), in order to find out which of these alloys could provide an intermediate band material used for fabricating high efficiency solar cell. Especially, among of these alloys, the electronic structure character and optical performance of Zn1-xCr∞ 0 alloys clearly show an intermediate band filled partially and isolated from the VB and the CB in energy band structure of ZnO host, and the intermediate band characters can be preserved with increasing Cr concentrations no more than 8.33% in Zn1-xCrxO alloys, at the same time, the ratio 0.52 of Eg^FC to EVE in Zn1-xCrxO, (x = 4.16%) alloy is closest to the optimal ratio of 0,57. Besides, compared to the ZnO, the optical absorption does indicate a great improved absorption below the calculated band gap of the ZnO and an enhancement of the optical absorption in the whole solar spectral energy range.
基金
Supported by the State Key Program for Basic Research of China under Grant No.2006CB921803
Project of High Technology Research&Development of China(Project No.2007AA03Z404)
National Natural Science Foundation of China under Grant Nos.61274058,60990312,and 61025020
Natural Science Foundation of Anhui Province under Grant No.1208085QF116