高活性晶面锐钛矿型TiO2纳米材料的溶剂热法制备及其光催化性能

以钛酸四丁酯为钛源,通过温和的溶剂热法制备了{101}/111]-晶面共暴露(乙酸-TiO_2和无控制剂-TiO_2,即HAc-TiO_2和NO-TiO_2)和{101}/{010}/111]-晶面共暴露(甲酸-TiO_2和氢氟酸-TiO_2,即FA-TiO_2和HF-TiO_2)的锐钛矿型TiO_2纳米材料,对其晶体结构、形貌、比表面积、孔径分布、光学性质以及载流子(电子和空穴)的迁移和重组进行了表征,并对其光催化性能和循环性能进行了评价。研究表明,所制备的{101}/{010}/111]-晶面共暴露的HF-TiO_2在光催化降解罗丹明B溶液(或对硝基苯酚溶液)的过程中显示了最高的光催化活性,其降解效率为97.35%(或68.57%),分别是FA-TiO_2、HAc-TiO_2、BD-TiO_2和NO-TiO_2的1.06倍(或1.09倍)、1.18倍(或1.14倍)、1.35倍(或2.33倍)和4.88倍(或5.80倍),这归因于其最高的结晶性、较大的表面能、优越的表面原子结构和表面电子结构、最低的光致发光强度、最快的电荷转移速率和最小的载流子复合率。

Solvothermal Synthesis of High-Reactive Faceted Anatase TiO2 Nanomaterials with Improved Photocatalytic Performance

Herein, anatase TiO₂ nanoparticles with co-exposed {101}/111]-facets (ethanoic acid-TiO₂ and no control agent-TiO₂, namely HAc-TiO₂ and NO-TiO₂) and co-exposed {101}/{010}/111]-facets (formic acid-TiO₂ and hydrofluoric acid-TiO₂, namely FA-TiO₂ and HF-TiO₂) were prepared by a mild solvothermal method using tetrabutyl titanate as titanium source. The crystal structure, morphology, specific surface area, pore size distribution, optical properties, transformation and recombination of charge carriers (electron and hole) of the samples were characterized. The photocatalytic performance and cycling performance of the samples were also evaluated. The results showed that as-prepared HF-TiO₂ with co-exposed {101}/{010}/111]-facets exhibited the highest photocatalytic activity in the process of photocatalytic degradation of rhodamine B solution (or p-nitrophenol solution), and its degradation efficiency was 97.35% (or 68.57%), which was 1.06 times (or 1.09 times), 1.18 times (or 1.14 times), 1.35 times (or 2.33 times) and 4.88 times (or 5.80 times) of FA-TiO₂, HAc-TiO₂, BD-TiO₂ and NO-TiO₂, respectively. The highest photocatalytic activity of HF-TiO₂ could be attributed to the synergistic effect of the maximum crystallinity, larger surface energy, superior surface atomic structure and surface electronic structure, lowest photoluminescence intensity, fastest charge transfer rate and minimum carrier recombination rate.