Catalytic Transfer Hydrogenation (CTH) of unsaturated functional groups to obtain high value-added products has attracted considerable attention in heterogeneous catalysis. Herein, we report a Ni single atoms (SAs) catalyst anchoring to MgAl mixed metal oxide (MMO) based on structural topotactic transformation from hydrotalcite precursor, which displays an excellent catalytic behavior toward CTH of cinnamaldehyde (CAL) to cinnamyl alcohol (COL) (conversion: 100%; selectivity: 100%; 2 h). A combination research including AC-STEM, XAFS and in situ CO-IR demonstrates that Ni species anchored by NiO coordination with different dispersion could be precisely obtained by tuning the reduction temperature: the Ni SAs (only NiO coordination) were obtained below 450 °C, and the NiNi coordination appears and increases gradually with the rise of the reduction temperature. The selective poisoning experiment, kinetic isotope effect (KIE), in situ FT-IR measurement and DFT calculation reveal the synergistic effect between metal Ni SAs and acid–base sites toward CTH of CAL. Specifically, the Ni SAs play a crucial role in dehydrogenation reaction of 2-propanol (2-POL) to supply activated H, the base sites induce α-CH cleavage in 2-POL (the rate-determining step), and the Lewis acid sites serve as the active center for CO adsorption in CAL molecule. This work demonstrates a synergetic effect between Ni SAs and acid–base sites, which would pave the way in the rational design and synthesis of high-performance SAs materials used in CTH reactions.

不饱和官能团的催化转移加氢（CTH）获得高附加值的产品在多相催化中引起了相当大的关注。在本文中，我们报道了基于水滑石前体的结构电位转变而固定在Mg Al混合金属氧化物（MMO）上的Ni单原子（SAs）催化剂，该催化剂对肉桂醛（CAL）的CTH转化为肉桂醇（COL）表现出优异的催化性能。 （转化率：100％；选择性：100％； 2小时）。包括AC-STEM，XAFS和原位CO-IR在内的组合研究表明，通过调节还原温度，可以精确地获得由Ni O配位而分散度不同的Ni物种：在450以下获得Ni SAs（仅Ni O配位） °C和镍Ni的配位随着还原温度的升高而出现并逐渐增加。选择性中毒实验，动力学同位素效应（KIE），原位FT-IR测量和DFT计算揭示了金属Ni SA与酸碱位点对CAL的CTH的协同作用。具体来说，Ni SAs在2-丙醇（2-POL）的脱氢反应中提供活化的H，起关键作用，碱基诱导2-POL中的α- C H裂解（决定速率的步骤），以及Lewis酸性位点是C的活性中心CAL分子中的O吸附。这项工作证明了镍SA与酸碱位之间的协同作用，这将为合理设计和合成用于CTH反应的高性能SAs材料铺平道路。