Key Laboratory of the Ministry of Education for Advanced Catalysis Materials, Institute of Physical Chemistry, Zhejiang Normal University, Jinhua, 321004, P.R. China.
Dalton Trans. 2013 Jan 28;42(4):1122-8. doi: 10.1039/c2dt32040a.
TiO(2)-Ag hybrid hollow spheres (about 700 nm in diameter) with a highly uniform morphology and good structural stability were facilely prepared via a one-pot hydrothermal method, using carbon spheres as templates followed by an annealing treatment. Through this route, the as-prepared hybrid hollow spheres preserved the uniformity of the initial carbon sphere templates and the loading amount of the Ag nanocrystals can be conveniently varied or controlled by the concentration of the Ag precursor. The investigation of the photocatalytic ability demonstrated that the as-prepared TiO(2)-Ag hybrid hollow spheres possess excellent photocatalytic activity, superior to commercial TiO(2) nanoparticles (Degussa P25), for the degradation of rhodamine B (RhB) and methyl orange (MO) dyes under visible-light illumination. Furthermore, the ˙OH radicals formed during photocatalysis with different Ag content hybrids were revealed by means of a terephthalic acid fluorescence probe method, which uncovers that the Ag content in the TiO(2)-Ag hybrids was crucial to obtain an optimal synergistic effect between the Ag and TiO(2) for the degradation of organic pollutants. Accordingly, the optimum matching for the best photocatalytic activity was investigated thoroughly and a reasonable mechanism was also proposed.
TiO(2)-Ag 杂化中空球（直径约 700nm）具有高度均匀的形态和良好的结构稳定性，通过一步水热法，以碳球为模板，经退火处理制备得到。通过这种方法，所制备的杂化中空球保留了初始碳球模板的均匀性，并且通过改变 Ag 前驱体的浓度，可以方便地改变或控制 Ag 纳米晶体的负载量。光催化能力的研究表明，所制备的 TiO(2)-Ag 杂化中空球具有优异的光催化活性，在可见光照射下，对于罗丹明 B（RhB）和甲基橙（MO）染料的降解，优于商业 TiO(2)纳米颗粒（Degussa P25）。此外，通过使用对苯二甲酸荧光探针法揭示了不同 Ag 含量杂化光催化过程中形成的˙OH 自由基，这表明 TiO(2)-Ag 杂化中 Ag 的含量对于获得 Ag 和 TiO(2)之间的最佳协同效应以降解有机污染物至关重要。因此，深入研究了最佳光催化活性的最佳匹配，并提出了合理的机制。
