School of Environmental Science and Engineering , Shaanxi University of Science and Technology , Xi'an 710021 , China.
Program for the Environment and Sustainability, Department of Occupational and Environmental Health, School of Public Health , Texas A&M University , College Station , Texas 77843 , United States.
Environ Sci Technol. 2019 Apr 2;53(7):3610-3619. doi: 10.1021/acs.est.9b01176. Epub 2019 Mar 14.
The application of tandem catalysis is rarely investigated in degrading organic pollutants in the environment. Herein, a tandem catalyst on single platinum (Pt) nanoparticles (Pt NPs) is prepared for the sequential degradation of formaldehyde (HCHO) to carbon dioxide gas [CO(g)] at room temperature. The synthesis approach includes coating of uniform Pt NPs on SrBiTaO platelets using a photoreduction process, followed by calcination of the sample in the atmosphere to tune partial transformation of Pt atoms to Pt ions in the tandem catalyst. The conversion of HCHO to CO(g) is monitored by in situ Fourier transform infrared spectroscopy, which shows first conversion of HCHO to CO ions onto Pt active sites and subsequently the conversion of CO ions to CO(g) by neighboring Pt species of the catalyst. The later process with Pt species does not allow CO poisoning of the catalyst. The enhanced activity of the prepared tandem catalyst to oxidize HCHO is maintained continuously for 680 min. Comparatively, the catalyst without Pt shows activity for only 40 min. Additionally, the tandem catalyst presented herein performs better than the Pt/titanium dioxide (TiO) catalyst to degrade HCHO. Overall, the tandem catalyst may be applied to degrade organic pollutants efficiently.
串联催化在环境中降解有机污染物的应用研究甚少。本文制备了一种负载在 SrBiTaO 薄片上的单铂（Pt）纳米粒子（Pt NPs）串联催化剂，用于在室温下顺序降解甲醛（HCHO）为二氧化碳气体[CO(g)]。该合成方法包括用光还原法在 SrBiTaO 薄片上均匀包覆 Pt NPs，然后在空气中对样品进行煅烧，以调整串联催化剂中部分 Pt 原子向 Pt 离子的转化。通过原位傅里叶变换红外光谱监测 HCHO 的转化，结果表明 HCHO 首先转化为 CO 离子到 Pt 活性位上，然后相邻的 Pt 物种将 CO 离子进一步转化为 CO(g)。后一过程中，Pt 物种不会使催化剂中毒。所制备的串联催化剂氧化 HCHO 的活性可连续保持 680 分钟。相比之下，没有 Pt 的催化剂的活性仅为 40 分钟。此外，本文提出的串联催化剂在降解 HCHO 方面的性能优于 Pt/二氧化钛（TiO）催化剂。总的来说，该串联催化剂可用于高效降解有机污染物。
