PDF《B01.光催化材料》

1501520 B01-K-04 The inhibition of hydrogen and oxygen recombination by halogen atoms and its effect on over-all water splitting over Pt-TiO2 吕功煊 中国科学院兰州化学物理研究所 Semiconductor photocatalysts for overall water splitting into H2 and O2 require metal cocatalyst, such as Pt, to catalyze H2 evolution efficiently. However, these metal cocatalysts can also catalyze hydrogen and oxygen recombination to form water. In this work, we found that the pre-adsorbed halogen atom catalyst could inhibit the reverse reaction of water formation from H2 and O2 due to the decrease of adsorption energies of H2 and O2 on Pt. The adsorption energy decrease of H2 and O2 followed the order of F/Pt <

Cl/Pt <

I/Pt <

Br/Pt. This inhibition was achieved via the occupation of halogen atom on the Pt surface sites, and thereby the adsorption and activation of hydrogen and oxygen molecules were decreased. The occupation difference of halogen atoms are determined by radius of halogen ions, which further leads the different activity for H2 and O2 recombination. The over-all water splitting over various TiO2 photocatalysts has been achieved. Isotope experiments with D2O and H2

18 O confirmed the over-all water splitting to H2 and O2. This study may help scientist to develop high-efficient photocatalyst for overall water splitting. B01-K-05 红色 TiO2 光催化材料 刘岗 1.中国科学院金属研究所 2.中国科学技术大学 The strong band-to-band absorption of photocatalysts spanning the whole visible light region is critically important for solar- driven photocatalysis. Although it is actively and widely used as photocatalyst for various reactions in the past four decades, TiO2 has poor ability to efficiently capture the whole-spectrum visible light. By controlling the spatially homogeneous distribution of electronic structure modifiers (heteroatoms &

hydrogen filled oxygen vacancies) in anatase TiO2 microspheres, a strong band-to- band visible light absorption spectrum with a sharp absorption edge beyond

600 nm can be achieved. The red anatase TiO2 has photo(electro)catalytic water oxidation ability to produce oxygen under visible light with its wavelength beyond

550 nm. These results demonstrate the great promise of using TiO2 for visible light photocatalytic water oxidation and also provide a possible strategy for realizing the wide-spectrum visible light absorption o........