State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences, 27 South Taoyuan Road, Taiyuan, 030001, P. R. China.
University of Chinese Academy of Sciences, Beijing, 100049, P. R. China.
Angew Chem Int Ed Engl. 2018 Feb 12;57(7):1836-1840. doi: 10.1002/anie.201710605. Epub 2018 Jan 16.
Identification of the active copper species, and further illustration of the catalytic mechanism of Cu-based catalysts is still a challenge because of the mobility and evolution of Cu and Cu species in the reaction process. Thus, an unprecedentedly stable Cu-based catalyst was prepared by uniformly embedding Cu nanoparticles in a mesoporous silica shell allowing clarification of the catalytic roles of Cu and Cu in the dehydrogenation of methanol to methyl formate by combining isotope-labeling experiment, in situ spectroscopy, and DFT calculations. It is shown that Cu sites promote the cleavage of the O-H bond in methanol and of the C-H bond in the reaction intermediates CH O and H COOCH which is formed from CH O and HCHO, whereas Cu sites cause rapid decomposition of formaldehyde generated on the Cu sites into CO and H .
由于铜和铜物种在反应过程中的迁移和演变，鉴定活性铜物种，并进一步阐明铜基催化剂的催化机理仍然是一个挑战。因此，通过将纳米铜颗粒均匀嵌入介孔硅壳中，制备了一种前所未有的稳定的铜基催化剂，通过结合同位素标记实验、原位光谱和 DFT 计算，澄清了铜和铜在甲醇脱氢生成甲酸甲酯反应中的催化作用。结果表明，Cu 位促进甲醇中 O-H 键和反应中间体 CHO 和 HCOOCH 中 C-H 键的断裂，CHO 和 HCHO 生成 HCOOCH，而 Cu 位则导致 Cu 位上生成的甲醛迅速分解为 CO 和 H。
