Department of Chemistry, East China Normal University, Shanghai 200062, PR China.
Nanoscale. 2013 Mar 7;5(5):1876-81. doi: 10.1039/c2nr33755j. Epub 2013 Jan 24.
A novel mesoporous yolk-shell SnS(2)-TiO(2) visible photocatalyst (ST-is) was synthesized by in situ doping TiO(2) with SnO(2) through solvothermal alcoholysis, followed by sulfurization under hydrothermal conditions. The ST-is displayed higher activity in photocatalytic reduction of Cr(VI) owing to the strong photosensitizing effect of SnS(2) in uniform nanoparticles and the enhanced light harvesting via multiple reflections in yolk-shell chambers. Meanwhile, the strong SnS(2)-TiO(2) interaction could generate more heterojunctions which facilitated photoelectron transfer from SnS(2) to TiO(2), leading to the enhanced activity by inhibiting photoelectron-hole recombination. Moreover, the ST-is displayed strong durability owing to the strong SnS(2)-TiO(2) interaction and the encapsulation of SnS(2) nanoparticles in the yolk-shell chamber, which could inhibit SnS(2) leaching. Furthermore, because of the electronegative surface and high surface area, the ST-is could thoroughly purify wastewater by completely adsorbing Cr(3+) resulting from Cr(VI) reduction. In addition, the presence of photocatalytic degradation of organic compounds promoted Cr(VI) reduction owing to inhibition of photoelectron-hole recombination by consuming holes.
一种新型的介孔蛋黄壳型 SnS(2)-TiO(2)可见光光催化剂（ST-is）是通过溶剂热醇解原位掺杂 SnO(2)与 TiO(2)，然后在水热条件下硫化合成的。ST-is 在光催化还原 Cr(VI)方面表现出更高的活性，这是由于 SnS(2)在均匀纳米颗粒中的强光敏效应和通过蛋黄壳腔中的多次反射增强了光捕获。同时，强的 SnS(2)-TiO(2)相互作用可以产生更多的异质结，促进光电子从 SnS(2)向 TiO(2)的转移，从而抑制光生电子-空穴复合，提高活性。此外，由于强的 SnS(2)-TiO(2)相互作用和 SnS(2)纳米颗粒在蛋黄壳腔中的封装，ST-is 显示出很强的耐久性，这可以抑制 SnS(2)的浸出。此外，由于具有负电性表面和高表面积，ST-is 可以通过完全吸附 Cr(3+)（由 Cr(VI)还原产生）来彻底净化废水。此外，由于有机化合物的光催化降解抑制了光生电子-空穴复合，从而消耗空穴，促进了 Cr(VI)的还原。
