(1. 廣西大學(xué) 化學(xué)化工學(xué)院,南寧 530004;
2. 廣西大學(xué) 資源與冶金學(xué)院,南寧 530004;
3. 廣西民族大學(xué) 化學(xué)與生態(tài)工程學(xué)院,南寧 530006;
4. 廣西大學(xué) 物理科學(xué)與工程技術(shù)學(xué)院,南寧 530004)
摘 要: 采用密度泛函理論對氧分子在黃鐵礦和方鉛礦表面的吸附進行研究。計算結(jié)果表明:黃鐵礦和方鉛礦表面經(jīng)歷了較小的弛豫;氧分子在黃鐵礦和方鉛礦表面都呈解離吸附狀態(tài),且在黃鐵礦表面的吸附能遠低于在方鉛礦表面的吸附能;在黃鐵礦表面上,氧原子分別與鐵原子和硫原子鍵合,電子由鐵原子和硫原子轉(zhuǎn)移到氧原子上,主要由硫的3p態(tài)、氧的2p態(tài)和鐵的3d態(tài)參與反應(yīng),鐵與氧之間形成d→p反饋鍵,而在方鉛礦表面上,氧原子只與硫原子鍵合,主要由硫的3p態(tài)、氧的2p態(tài)和鉛的6p態(tài)參與反應(yīng),未形成反饋鍵;氧吸附后黃鐵礦表面產(chǎn)生鍵合的鐵原子和氧原子都產(chǎn)生自旋現(xiàn)象,而方鉛礦表面原子及吸附的氧原子仍然是低自旋態(tài)的。
關(guān)鍵字: 黃鐵礦;方鉛礦;氧分子吸附;密度泛函理論
(1. School of Chemistry and Chemical Engineering, Guangxi University, Nanning 530004, China;
2. College of Resources and Metallurgy, Guangxi University, Nanning 530004, China;
3. College of Chemistry and Ecoengineering, Guangxi University for Nationalities, Nanning 530006, China;
4. College of Physics Science and Engineering, Guangxi University, Nanning 530004, China)
Abstract:The adsorption of oxygen molecule (O2) on the pyrite and galena surfaces was studied using density functional theory (DFT). The calculated results show that the surface relaxation of pyrite and galena is small. O2 dissociates after adsorption on the pyrite and galena surfaces, and the adsorption energy of O2 on pyrite is much lower than that on the galena. On the pyrite surface, oxygen atom (O) bonds with sulfur (S) and iron (Fe) atoms and the electrons are transferred from Fe and S atoms to O, and the reactions are mainly S 3p, O 2p and Fe 3d states involved, forming the d→p back bonding between Fe and O. While on the galena surface, oxygen atom only bonds with sulfur atom, and the reactions are mainly S 3p, O 2p and Pb 6p states involved, without forming d→p back bonding. The bonded Fe and O atoms are spin-polarized after the adsorption of O2, while the galena surface atoms and adsorbed O atom are still low-spin states.
Key words: pyrite; galena; O2 adsorption; density functional theory


