(1. 福州大學(xué) 材料科學(xué)與工程學(xué)院,福州 350108;
2. 福州大學(xué) 材料研究所,福州 350108)
摘 要: 采用基于密度泛函理論的投影綴加平面波方法和廣義梯度近似計(jì)算了螢石相ZrO2及摻雜Ru形成的復(fù)合氧化物的晶體結(jié)構(gòu)、電子結(jié)構(gòu)、內(nèi)聚能以及Bader電荷。結(jié)果表明:螢石相ZrO2和RuO2的點(diǎn)陣參數(shù)與文獻(xiàn)報(bào)道的數(shù)值基本相符。螢石相ZrO2中摻入Ru后,體系的晶胞形狀發(fā)生微小變形且晶胞體積減小;體系由直接帶隙半導(dǎo)體轉(zhuǎn)變?yōu)殚g接帶隙半導(dǎo)體,帶隙從3.06 eV減小至1.03 eV。對(duì)比Ru摻雜前后ZrO2的內(nèi)聚能、態(tài)密度和Bader電荷變化發(fā)現(xiàn),Ru摻雜后體系的離子性增強(qiáng),共價(jià)性減弱。
關(guān)鍵字: (Ru0.125, Zr0.875)O2;第一性原理計(jì)算;內(nèi)聚能;Bader電荷布居
(1. College of Materials Science and Engineering, Fuzhou University, Fuzhou 350108, China;
2. Institute of Materials Research, Fuzhou University, Fuzhou 350108, China)
Abstract:The crystal structures, electronic structures, cohesive energies, and the Bader charges of fluorite ZrO2 and Ru-doped ZrO2 composite oxide were investigated by using projector augmented wave method and the generalized gradient approximation based on density functional theory. The results show that the calculated equilibrium lattice parameters of cubic ZrO2 and RuO2 are in good agreement with the available literatures. By adding Ru into fluorite ZrO2, the cell shape changes slightly and cell volume is reduced, the system changes from direct-band-gap semiconductor to indirect-band-gap semiconductor, and the forbidden gap width is reduced from 3.6 eV to 1.03 eV. Comparing the changes of cohesive energy, density of states and Bader charges of ZrO2 before and after doping shows that the ionic character is enhanced and the covalent character is weakened by adding Ru into fluorite ZrO2.
Key words: (Ru0.125, Zr0.875)O2; first-principles calculation; cohesive energy; Bader population


