Department of Chemical and Biological Engineering, Tufts University , 4 Colby Street, Medford, Massachusetts 02155, United States.
Department of Chemistry, Tufts University , 62 Talbot Avenue, Medford, Massachusetts 02155, United States.
J Am Chem Soc. 2016 May 25;138(20):6396-9. doi: 10.1021/jacs.6b03339. Epub 2016 May 17.
Platinum catalysts are extensively used in the chemical industry and as electrocatalysts in fuel cells. Pt is notorious for its sensitivity to poisoning by strong CO adsorption. Here we demonstrate that the single-atom alloy (SAA) strategy applied to Pt reduces the binding strength of CO while maintaining catalytic performance. By using surface sensitive studies, we determined the binding strength of CO to different Pt ensembles, and this in turn guided the preparation of PtCu alloy nanoparticles (NPs). The atomic ratio Pt:Cu = 1:125 yielded a SAA which exhibited excellent CO tolerance in H2 activation, the key elementary step for hydrogenation and hydrogen electro-oxidation. As a probe reaction, the selective hydrogenation of acetylene to ethene was performed under flow conditions on the SAA NPs supported on alumina without activity loss in the presence of CO. The ability to maintain reactivity in the presence of CO is vital to other industrial reaction systems, such as hydrocarbon oxidation, electrochemical methanol oxidation, and hydrogen fuel cells.
铂催化剂在化学工业中被广泛应用，并作为燃料电池中的电催化剂。铂因对强 CO 吸附的敏感性而臭名昭著。在这里，我们证明应用于 Pt 的单原子合金 (SAA) 策略降低了 CO 的结合强度，同时保持了催化性能。通过使用表面敏感研究，我们确定了 CO 与不同 Pt 集合体的结合强度，这反过来又指导了 PtCu 合金纳米粒子 (NPs) 的制备。原子比 Pt:Cu = 1:125 得到的 SAA 在 H2 活化中表现出优异的 CO 耐受性，H2 活化是加氢和氢电氧化的关键基本步骤。作为探针反应，在 CO 存在下，在氧化铝负载的 SAA NPs 上进行乙炔的选择性加氢制乙烯，在反应过程中没有活性损失。在 CO 存在下保持反应性的能力对于其他工业反应系统（如烃氧化、电化学甲醇氧化和氢燃料电池）至关重要。
