Key Laboratory of Computational Physical Sciences (Ministry of Education), and Department of Physics, Fudan University, Shanghai 200433, P. R. China.
Phys Chem Chem Phys. 2013 Feb 14;15(6):1778-81. doi: 10.1039/c2cp44484d. Epub 2012 Dec 20.
The formation of (TiO(2))(x)(Cu(2)O)(y) solid-solutions is investigated using a global optimization evolutionary algorithm. First-principles calculations based on density functional theory are then used to gain insight into the electronic properties of these alloys. We find that: (i) Ti and Cu in (TiO(2))(x)(Cu(2)O)(y) alloys have similar local environments as in bulk TiO(2) and Cu(2)O except for (TiO(2))(Cu(2)O) which has some trigonal-planar Cu ions. (ii) The predicted optical band gaps are around 2.1 eV (590 nm), thus having much better performance in the absorption of visible light compared with both binary oxides. (iii) (TiO(2))(2)(Cu(2)O) has the lowest formation energy amongst all studied alloys and the positions of its band edges are found to be suitable for solar-driven water splitting applications.
使用全局优化进化算法研究了(TiO2)x(Cu2O)y 固溶体的形成。然后，基于密度泛函理论的第一性原理计算被用来深入了解这些合金的电子特性。我们发现：(i)TiO2 和 Cu2O 中的 Ti 和 Cu 在 (TiO2)x(Cu2O)y 合金中的局部环境与体相 TiO2 和 Cu2O 中的相似，除了 (TiO2)(Cu2O) 中具有一些三角平面 Cu 离子。(ii) 预测的光学带隙约为 2.1 eV(590nm)，因此与两种二元氧化物相比，在可见光吸收方面性能更好。(iii)(TiO2)2(Cu2O)在所有研究的合金中具有最低的形成能，并且其能带边缘的位置被发现适合于太阳能驱动的水分解应用。
