Theoretical research on transition metal-doped TiO2 is of great importance to develop the photocatalytic applications. First-principles calculation of doped TiO2 is still an ongoing subject, and a few challenging problems require further investigation in an urgent demand. One is the influence of the transition metal doping on the phase transition of TiO2 from anatase to rutile. A theoretical understanding on its mechanism will be useful to optimize the performance

of TiO2 in photocatalytic and other applications. Another one is the question about using the virtual crystal approximation method to calculate the doping system for very low concentration, Combretastatin A4 mouse which can cut down the calculation time. With the solution of these problems, one could provide more

accurate theoretical models to simulate the practical doping approaches which could lead to important implications in the optimization of the performance of transition metal-doped TiO2 selleck screening library photocatalysts. 17-AAG clinical trial Acknowledgements This work was supported by the National Nature Science Foundation of China (51162007 and 51202050), Hainan Natural Science Foundation (511110), and Tsinghua University Initiative Scientific Research Program. References 1. Fujishima A, Honda K: Electrochemical photolysis of water at a semiconductor electrode. Nature 1972, 23:37–38.CrossRef 2. Yang K, Dai Y, Huang B, Han S: Theoretical study of N-doped TiO 2 rutile crystals. J Phys Chem B 2006, 110:24011–24014.CrossRef 3. Li SP, Lin SW, Liao JJ, Pan NQ, Li DH, Li JB: Nitrogen-doped TiO 2 nanotube

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