Dependence of kinetics and pathway of acetaminophen photocatalytic degradation on irradiation photon energy and TiO2 crystalline
Dependence of kinetics and pathway of acetaminophen photocatalytic degradation on irradiation photon energy and TiO2 crystalline
复制标题
对乙酰氨基酚光催化降解的动力学和途径对辐照光子能量和 TiO2 结晶的依赖性
DOI：
10.1016/j.cej.2017.07.148
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发表时间：
2017-12-15
影响因子：
15.1
通讯作者：
Yang, Zixin
中科院分区：
文献类型：
--
作者：
Chen, Yuan;Zhang, Xu;Yang, Zixin
在宽光通量范围内，研究了对乙酰氨基酚（APAP）在锐钛矿型、金红石型和锐钛矿-金红石混合型TiO 2上的降解动力学和降解途径。羟基自由基（中心点OH）诱导的羟基化反应是APAP在含TiO 2光催化剂上降解的主要途径，占总降解量的50%以上。在UVA 366 nm照射下，APAP在金红石型TiO 2上的单电子氧化反应约占70%;在UVC 254 nm照射下，由于APAP与金红石型TiO 2之间对照射光子的竞争，APAP在金红石型TiO 2上的直接光解反应贡献大于金红石型TiO 2。结果表明，中心点OH和h（VB）对金红石型TiO 2光催化降解APAP的贡献与辐照光子能量无关，而辐照光子能量显著影响中心点OH、h（VB）和直接光解对金红石型TiO 2光催化降解APAP的贡献。因此，可以通过改变辐照光子能量和TiO 2晶型来控制APAP及其它酚类物质在TiO 2光催化过程中的降解模式，使TiO 2光催化体系成为选择性氧化体系。
Degradation kinetics and pathway of acetaminophen (APAP) on anatase TiO2, rutile TiO2 and anatase-rutile mixed TiO2 were investigated at UVC 254 nm and UVA 366 nm in a wide photon flux region in the present work. Hydroxyl radicals (center dot OH) induced hydroxylation is the predominant pathway for the degradation of APAP on anatase or anatase containing TiO2 particularly under UVC irradiation, which accounted for more than 50% of total degradation. Valance band hole (h(VB)) induced one electron oxidation contributed approximately 70% of the degradation of APAP on rutile TiO2 under UVA 366 nm irradiation, while direct photolysis contributed more than rutile TiO2 photocatalysis under UVC 254 nm irradiation because of competition for irradiation photon between APAP and rutile TiO2. These results showed that contribution of center dot OH and h(VB) on anatase TiO2 is independent of irradiation photon energy, while irradiation photon energy significantly influences the contribution of center dot OH, h(VB) and direct photolysis to the degradation of APAP on rutile or rutile containing TiO2. Therefore, degradation patterns of APAP and maybe other phenols in TiO2 photocatalysis process could be controlled through changing irradiation photon energy and TiO2 crystalline, which will make TiO2 photocatalysis a selective oxidation system.