The electronic structure characters are calculated for the Zn_(1-x)M_xO 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 intermed...The electronic structure characters are calculated for the Zn_(1-x)M_xO 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 soiar cell.Especially,among of these alloys,the electronic structure character and optical performance of Zn_(1-x)Cr_xO alloys clearly show an intermediate band Med 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 Zn_(1-x)Cr_xO alloys,at the same time,the ratio 0.52 of E_g^(FC) to E_g^(VE) in Zn_(1-x)Cr_xO,(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.展开更多
基金Supported by the State Key Program for Basic Research of China under Grant No.2006CB921803Project of High Technology Research&Development of China(Project No.2007AA03Z404)+1 种基金National Natural Science Foundation of China under Grant Nos.61274058,60990312,and 61025020Natural Science Foundation of Anhui Province under Grant No.1208085QF116
文摘The electronic structure characters are calculated for the Zn_(1-x)M_xO 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 soiar cell.Especially,among of these alloys,the electronic structure character and optical performance of Zn_(1-x)Cr_xO alloys clearly show an intermediate band Med 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 Zn_(1-x)Cr_xO alloys,at the same time,the ratio 0.52 of E_g^(FC) to E_g^(VE) in Zn_(1-x)Cr_xO,(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.