TiO2@Pt@CeO2 nanocomposite as a bifunctional catalyst for enhancing photo-reduction of Cr (VI) and photo-oxidation of benzyl alcohol
TiO2@Pt@CeO2 nanocomposite as a bifunctional catalyst for enhancing photo-reduction of Cr (VI) and photo-oxidation of benzyl alcohol
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TiO2@Pt@CeO2 纳米复合材料作为双功能催化剂增强 Cr (VI) 的光还原和苯甲醇的光氧化
DOI：
10.1016/j.jhazmat.2017.12.001
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发表时间：
2018
影响因子：
13.6
通讯作者：
Zheng Fengying
中科院分区：
文献类型：
--
作者：
Li Shunxing;Cai Jiabai;Wu Xueqing;Liu Biwen;Chen Qiaoying;Li Yuehai;Zheng Fengying
设计了一种太阳光驱动的双功能光催化剂，用于在水存在下，室温条件下Cr（VI）的光还原和苯甲醇的选择性光氧化合成苯甲醛。采用功能化聚苯乙烯微球、溶胶-凝胶、水热反应、煅烧等方法制备了双层和夹心结构的TiO2@Pt@CeO2空心球。Pt纳米粒子（NPs）可控地负载在TiO 2壳和CeO 2壳之间。在太阳光照射下，Cr（VI）的光还原速率（μmol h−1）为TiO2@Pt@CeO2（1.901）> TiO2@CeO2（1.424）> TiO 2（1.040）> CeO 2（0.992）。在上述光催化剂中，TiO2@Pt@CeO2的苯甲醇转化率也最好。这主要归功于TiO 2和CeO 2作为光催化剂和氧缓冲剂的组合，双层夹心结构的纳米结构，以及Pt NPs作为助催化剂和电子捕获位点的加入，可以存储和穿梭光生电子，减少电子-空穴的复合，从而增强活性自由基的光生.电子顺磁共振（EPR）谱证实了这一结论。考虑到光催化剂、氧缓冲剂和助催化剂的多功能组合，该工作可以为设计用于重金属去除和选择性合成的高性能双功能光催化剂提供新的见解。
An solar-light-driven and bifunctional photocatalyst was designed for photo-reduction of Cr(VI) and selective photo-oxidation of benzyl alcohol into benzaldehyde in the presence of water under ambient conditions. Double-shelled and sandwiched TiO2@Pt@CeO2hollow spheres were prepared by using functionalized polystyrene spheres, sol-gel, hydrothermal reaction, and calcination. The Pt nanoparticles (NPs) were controllably loaded between the TiO2shell and CeO2shell. Under solar-light irradiation, the photo-reduction rate of Cr(VI) (μmol h−1) was in the order of TiO2@Pt@CeO2(1.901) > TiO2@CeO2(1.424) > TiO2(1.040) > CeO2(0.992). Among the above-mentioned photocatalysts, the conversion rate of benzyl alcohol for TiO2@Pt@CeO2was also the best. These results were attributed to the combination of TiO2and CeO2as photocatalyst and oxygen buffer, the double-shelled and sandwiched nanostructure, and the addition of Pt NPs as cocatalyst and electron trap site, which could store and shuttle photo-generated electrons, reduce the recombination of the electron-hole, and then enhance photo-generation of active radicals. This conclusion was verified by the electron paramagnetic resonance (EPR) spectroscopy. Considering the versatile combination of photocatalyst, oxygen buffer and cocatalyst, this work could provide new insights into the design of high-performance bifunctional photocatalysts for heavy metal removal and selective synthesis.