State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing100084, People's Republic of China.
School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing100083, People's Republic of China.
ACS Appl Mater Interfaces. 2023 Feb 15;15(6):7959-7968. doi: 10.1021/acsami.2c18716. Epub 2023 Feb 6.
With the environmental harm of unburnt CH in natural gas vehicle exhaust, oxidizing CH to CO over catalysts at low temperatures becomes an exigent issue. Supported Pd catalysts possess higher CH activity than other noble metal catalysts. A series of Pd/ZrO catalysts were synthesized to research the potential relationship among Pd particle morphology, electron transfer, CH oxidation mechanism, and catalytic activity. Characterizations show that the ratio of PdO facets to edge/corner sites on four catalysts increases in the order of PZ85 ≈ PZ40 < PZ55 < PZ70 because of the difference in content of surface -OH groups, and this order turns out to be the same as that of electron transfer intensity, revealing the degree of metal-support interactions. This kind of metal-support interaction in PZ70 can be helpful to accelerate CH combustion via promoting the break of the C-H bond and dissociation of CO* according to density functional theory studies. of the PZ70 catalyst with optimum catalytic activity reaches 331 °C.
由于天然气车尾气中未燃烧的 CH 对环境造成危害，因此在低温下将 CH 氧化为 CO 的催化剂成为当务之急。负载型 Pd 催化剂比其他贵金属催化剂具有更高的 CH 活性。本研究合成了一系列 Pd/ZrO 催化剂，以研究 Pd 颗粒形态、电子传递、CH 氧化机理和催化活性之间的潜在关系。表征结果表明，由于表面-OH 基团含量的差异，四种催化剂上 PdO 面与边缘/角位的比例按 PZ85≈PZ40<PZ55<PZ70 的顺序增加，这一顺序与电子传递强度的顺序相同，表明金属-载体相互作用的程度。根据密度泛函理论研究，PZ70 中的这种金属-载体相互作用有助于通过促进 C-H 键的断裂和 CO*的离解来加速 CH 的燃烧。具有最佳催化活性的 PZ70 催化剂的起燃温度达到 331°C。
