Key Laboratory of Beijing on Regional Air Pollution Control, Beijing Key Laboratory for Green Catalysis and Separation, Beijing University of Technology, Beijing 100124, China; Advanced E-Catal. Corporation, Ltd., Beijing 100025, China.
Key Laboratory of Beijing on Regional Air Pollution Control, Beijing Key Laboratory for Green Catalysis and Separation, Beijing University of Technology, Beijing 100124, China.
J Environ Sci (China). 2025 Feb;148:57-68. doi: 10.1016/j.jes.2023.08.005. Epub 2023 Aug 16.
The expandable graphite (EG) modified TiO nanocomposites were prepared by the high shear method using the TiO nanoparticles (NPs) and EG as precursors, in which the amount of EG doped in TiO was 10 wt.%. Followed by the impregnation method, adjusting the pH of the solution to 10, and using the electrostatic adsorption to achieve spatial confinement, the Pt elements were mainly distributed on the exposed TiO, thus generating the Pt/10EG-TiO-10 catalyst. The best CO oxidation activity with the excellent resistance to HO and SO was obtained over the Pt/10EG-TiO-10 catalyst: CO conversion after 36 hr of the reaction was ca. 85% under the harsh condition of 10 vol.% HO and 100 ppm SO at a high gaseous hourly space velocity (GHSV) of 400,000 hr. Physicochemical properties of the catalysts were characterized by various techniques. The results showed that the electrostatic adsorption, which riveted the Pt elements mainly on the exposed TiO of the support surface, reduced the dispersion of Pt NPs on EG and achieved the effective dispersion of Pt NPs, hence significantly improving CO oxidation activity over the Pt/10EG-TiO-10 catalyst. The 10 wt.% EG doped in TiO caused the TiO support to form a more hydrophobic surface, which reduced the adsorption of HO and SO on the catalyst, greatly inhibited deposition of the TiOSO and formation of the PtSO species as well as suppressed the oxidation of SO, thus resulting in an improvement in the resistance to HO and SO of the Pt/10EG-TiO-10 catalyst.
可膨胀石墨 (EG) 改性 TiO 纳米复合材料通过高剪切方法制备，使用 TiO 纳米颗粒 (NPs) 和 EG 作为前体，其中掺杂的 EG 量为 10wt%。然后通过浸渍法，将溶液的 pH 值调节至 10，并利用静电吸附实现空间限制，Pt 元素主要分布在暴露的 TiO 上，从而生成 Pt/10EG-TiO-10 催化剂。Pt/10EG-TiO-10 催化剂具有优异的抗 H2O 和 SO2 性能，表现出最佳的 CO 氧化活性：在苛刻条件下（10vol.% H2O 和 100ppm SO2，GHSV 为 400,000hr-1），反应 36 小时后 CO 的转化率约为 85%。通过各种技术对催化剂的物理化学性质进行了表征。结果表明，静电吸附将 Pt 元素主要固定在载体表面暴露的 TiO 上，减少了 Pt NPs 在 EG 上的分散，实现了 Pt NPs 的有效分散，从而显著提高了 Pt/10EG-TiO-10 催化剂的 CO 氧化活性。TiO 中掺杂的 10wt% EG 使 TiO 载体形成更疏水的表面，减少了 H2O 和 SO2 在催化剂上的吸附，大大抑制了 TiOSO 的沉积和 PtSO 物种的形成，以及 SO2 的氧化，从而提高了 Pt/10EG-TiO-10 催化剂的抗 H2O 和 SO2 性能。
