Wu Fei, Wang Yueying, Fei Shunxin, Zhu Gang
Wuhan Institute of Marine Electric Propulsion, Wuhan 430064, China.
School of Materials Science & Engineering, Anhui University of Technology, Maanshan 243002, China.
Nanomaterials (Basel). 2023 Jun 26;13(13):1939. doi: 10.3390/nano13131939.
Bimetallic catalysts, especially non-noble metals, hold great potential for substituting for noble metals in catalytic hydrogenation. In present study, a series of CoNi ( + = 6) bimetallic catalysts were prepared through the impregnation-reduction method and cyclohexene was chosen as probe-molecule to study the promotion effect of Co on the catalytic olefin hydrogenation reactions. Meanwhile, density functional theory (DFT) was utilized to investigate the formation energies and the charge distribution of CoNi bimetals, as well as the transition state (TS) searches for hydrogen dissociation and migration. The results suggest that bimetals tend to have superior catalytic performance than pure metals, and CoNi shows the highest catalytic activity on the cyclohexene hydrogenation. It was found that the charge transfer from Co to Ni and the alloying give rise to the refinement of CoNi grains and the improvement of its catalytic activity and stability. Thus, it may be possible to obtain better catalytic performance by tuning the metal/metal atomic ratio of bimetals.
双金属催化剂，尤其是非贵金属催化剂，在催化氢化反应中替代贵金属方面具有巨大潜力。在本研究中，通过浸渍还原法制备了一系列CoNi（ += 6）双金属催化剂，并选择环己烯作为探针分子来研究Co对催化烯烃氢化反应的促进作用。同时，利用密度泛函理论（DFT）研究了CoNi双金属的形成能和电荷分布，以及氢解离和迁移的过渡态（TS）搜索。结果表明，双金属催化剂往往比纯金属具有更优异的催化性能，并且CoNi在环己烯氢化反应中表现出最高的催化活性。研究发现，从Co到Ni的电荷转移和合金化导致CoNi晶粒细化，及其催化活性和稳定性提高。因此，通过调整双金属的金属/金属原子比可能获得更好的催化性能。
