Gao Tianqi, Shen Yongli, Gu Lin, Zhang Zhaocheng, Yuan Wenjuan, Xi Wei
Center for Electron Microscopy, Tianjin Key Laboratory of Advanced Functional Porous Materials, Institute for New Energy Materials and Low-Carbon Technologies, School of Materials Science and Engineering, Tianjin University of Technology Tianjin 300384 China
RSC Adv. 2023 Jul 26;13(33):22710-22716. doi: 10.1039/d3ra03781a.
The excellent low-temperature oxidation performance and stability of nanogold catalysts have attracted significant interest. However, the main active source of the low-temperature oxidation of gold remains to be determined. electron microscopy and mass spectrometry results show that nitrogen is oxidized, and the catalyst surface undergoes reconstruction during the process. Strain analysis of the catalyst surface and first-principles calculations show that the tensile strain of the catalyst surface affects the oxidation performance of gold catalysts by enhancing the adsorption ability and dissociation of O. The newly formed active oxygen atoms on the gold surface act as active sites in the nitrogen oxidation reaction, significantly enhancing the oxidation ability of gold catalysts. This study provides evidence for the dissociation mechanism of oxygen on the gold surface and new design concepts for improving the oxidation activity of gold catalysts and nitrogen activation.
纳米金催化剂优异的低温氧化性能和稳定性引起了广泛关注。然而,金低温氧化的主要活性来源仍有待确定。电子显微镜和质谱结果表明,在此过程中氮被氧化,且催化剂表面发生重构。催化剂表面的应变分析和第一性原理计算表明,催化剂表面的拉伸应变通过增强对O的吸附能力和解离作用来影响金催化剂的氧化性能。金表面新形成的活性氧原子在氮氧化反应中充当活性位点,显著提高了金催化剂的氧化能力。本研究为金表面氧的解离机理提供了证据,并为提高金催化剂氧化活性和氮活化提供了新的设计理念。