Yang Weiping, Yu Haochen, Wang Beibei, Wang Xuemin, Zhang Hao, Lei Da, Lou Lan-Lan, Yu Kai, Liu Shuangxi
MOE Key Laboratory of Pollution Processes and Environmental Criteria, Tianjin Key Laboratory of Environmental Technology for Complex Transmedia Pollution, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China.
Institute of New Catalytic Materials Science, School of Materials Science and Engineering, National Institute of Advanced Materials, Nankai University, Tianjin 300350, China.
ACS Appl Mater Interfaces. 2022 Aug 24;14(33):37667-37680. doi: 10.1021/acsami.2c07065. Epub 2022 Aug 14.
The interfacial oxygen-defective sites of oxide-supported metal catalysts are generally regarded as active centers in diverse redox reactions. Identification of their structure-property relationship at the atomic scale is of great importance but challenging. Herein, a series of La-doped three-dimensionally ordered macroporous CeO (3D-CeLaO) were synthesized and applied as supports for Pt nanoparticles. The pieces of evidence from a suite of in-situ/ex-situ characterizations and theoretical calculations revealed that the La-mono-substituted La-□(-Ce) sites (where □ represents an oxygen vacancy) exhibited superior charge transfer ability, behaving as trapping centers for Pt nanoparticles. The resulting interfacial Pt/La-□(-Ce) sites served as the reversible active species in the aerobic oxidation of 5-hydroxymethylfurfural to boost catalytic performance by simultaneously promoting oxygen activated capacity and the cleavage of O-H/C-H bonds of adsorbed hydroxymethyl groups. Consequently, the Pt/3D-CeLaO catalyst possessing the highest number of Pt/La-□(-Ce) sites showed the best catalytic performance with 99.6% yield to 2,5-furandicarboxylic acid in 10 h. These results offer more insights into the promoting mechanism of interfacial oxygen-defective sites for the liquid-phase aerobic oxidation of aldehydes and alcohols.
氧化物负载型金属催化剂的界面氧缺陷位点通常被视为多种氧化还原反应中的活性中心。在原子尺度上确定它们的结构-性能关系非常重要，但具有挑战性。在此，合成了一系列La掺杂的三维有序大孔CeO（3D-CeLaO）并用作Pt纳米颗粒的载体。一系列原位/非原位表征和理论计算的证据表明，La单取代的La-□(-Ce)位点（其中□代表氧空位）表现出优异的电荷转移能力，可作为Pt纳米颗粒的捕获中心。由此产生的界面Pt/La-□(-Ce)位点作为5-羟甲基糠醛有氧氧化中的可逆活性物种，通过同时促进氧活化能力和吸附的羟甲基基团的O-H/C-H键的裂解来提高催化性能。因此，具有最高数量Pt/La-□(-Ce)位点的Pt/3D-CeLaO催化剂表现出最佳的催化性能，在10小时内2,5-呋喃二甲酸的产率达到99.6%。这些结果为界面氧缺陷位点对醛和醇的液相有氧氧化的促进机制提供了更多见解。
