Department of Chemical and Environmental Engineering, University of California, Riverside, California 92521, United States.
ACS Appl Mater Interfaces. 2013 Jul 10;5(13):6247-54. doi: 10.1021/am401247h. Epub 2013 Jun 26.
Titanium dioxide is a semiconducting material that has been studied for many years as a photocatalytic material to degrade organics in water. This study investigated the effect of anatase-rutile mixtures and pH on the photocatalytic degradation of the dye Methylene blue as the target analyte. Anatase-rutile mixtures between 0 and 90% rutile that were synthesized from a water-soluble precursor were suspended at pH 4, 7, and 10. Suspension pH significantly affected the reactivity and efficiency of the photocatalysts because of the particle-particle and sorbate-surface interactions. The highest removal percentage of MB by 240 min at pH 4, 7, and 10 was 35, 99, and 93%, respectively. pH 7 was ideal to observe the affect of percent rutile on the degradation rate, where 91% was removed within 120 min by the material composed of 20% rutile, which is attributed to the synergistic charge transfer of holes from rutile to anatase.
二氧化钛是一种半导体材料，多年来一直被研究作为光催化材料来降解水中的有机物。本研究考察了锐钛矿-金红石混合物和 pH 值对作为目标分析物的亚甲基蓝染料光催化降解的影响。通过水可溶性前体制备的锐钛矿-金红石混合物在 pH 值为 4、7 和 10 时悬浮。悬浮液 pH 值由于颗粒-颗粒和吸附物-表面相互作用而显著影响光催化剂的反应性和效率。在 pH 值为 4、7 和 10 下，MB 在 240 分钟内的最高去除率分别为 35%、99%和 93%。pH 值为 7 是观察金红石百分含量对降解速率影响的理想条件，在 120 分钟内，由组成 20%金红石的材料去除了 91%的 MB，这归因于金红石向锐钛矿的空穴协同电荷转移。
