Vos Rafaël E, Koper Marc T M
Leiden Institute of Chemistry, Leiden University, P.O.Box 9502, 2300 RA Leiden, The Netherlands.
ACS Catal. 2024 Mar 8;14(7):4432-4440. doi: 10.1021/acscatal.4c00009. eCollection 2024 Apr 5.
Electrochemical CO reduction on Ni has recently been shown to have the unique ability to produce longer hydrocarbon chains in small but measurable amounts. However, the effects of the many parameters of this reaction remain to be studied in more detail. Here, we have investigated the effect of temperature, bulk CO concentration, potential, the reactant, cations, and anions on the formation of hydrocarbons via a chain growth mechanism on Ni. We show that temperature increases the activity but also the formation of coke, which deactivates the catalyst. The selectivity and thus the chain growth probability is mainly affected by the potential and the electrolyte composition. Remarkably, CO reduction shows lower activity but a higher chain growth probability than CO reduction. We conclude that hydrogenation is likely to be the rate-determining step and hypothesize that this could happen either by *CO hydrogenation or by termination of the hydrocarbon chain. These insights open the way to further development and optimization of Ni for electrochemical CO reduction.
最近研究表明，镍上的电化学一氧化碳还原反应具有独特能力，能够以少量但可测量的量生成更长的碳氢化合物链。然而，该反应诸多参数的影响仍有待更详细地研究。在此，我们通过镍上的链增长机制，研究了温度、本体一氧化碳浓度、电势、反应物、阳离子和阴离子对碳氢化合物形成的影响。我们发现，温度会提高活性，但也会导致焦炭形成，从而使催化剂失活。选择性以及链增长概率主要受电势和电解质组成的影响。值得注意的是，与一氧化碳还原相比，一氧化碳还原活性较低，但链增长概率较高。我们得出结论，氢化作用可能是速率决定步骤，并推测这可能通过*一氧化碳氢化或碳氢化合物链的终止发生。这些见解为镍用于电化学一氧化碳还原的进一步开发和优化开辟了道路。
