CO methanation is an effective way for CO recycling, and nickel-based catalysts have attracted much attention in this field due to their excellent CH selectivity and cost-effectiveness; however, their applications are limited by their suboptimal catalytic activity. In this work, the catalytic activity of Ni-rutile-based catalysts was increased by almost an order of magnitude simply by doping the rutile with Fe. Series characterizations show that three factors that mainly contributed to the improved catalytic performance of the Ni/Fe-Rutile, which are the reduction of the Ni size, the increase of the basic sites, and the inhibition of the encapsulation of the Ni particles by the support. With Fe doping, the OH and oxygen vacancies on the rutile surface were reduced, which made the support difficult to reduce and thus suppressed the encapsulation of Ni by the support. As a result, the number of exposed active sites on the Ni/Fe-Rutile which with a smaller Ni size was further successfully increased, and the catalytic activity was significantly improved. This study provides new ideas for the design of activity-enhanced supported catalysts from the perspective of tuning the metal-support interaction and may be applicable to other reducible oxide-supported metal catalysts.

中文翻译：

---

通过 Fe 掺杂调节金属-载体相互作用增强镍金红石基催化剂的 CO2 甲烷化活性

CO甲烷化是CO回收的有效途径，镍基催化剂因其优异的CH选择性和成本效益而在该领域备受关注；然而，它们的应用受到次优催化活性的限制。在这项工作中，仅通过在金红石中掺杂 Fe，镍金红石基催化剂的催化活性就提高了几乎一个数量级。系列表征表明，Ni/Fe-金红石催化性能提高的主要原因是三个因素：Ni尺寸的减小、碱性位点的增加以及Ni颗粒对Ni颗粒包封的抑制。支持。 Fe掺杂后，金红石表面的OH和氧空位减少，使得载体难以还原，从而抑制了载体对Ni的包封。结果，具有较小Ni尺寸的Ni/Fe-金红石上暴露的活性位点数量进一步成功增加，催化活性显着提高。该研究从调节金属-载体相互作用的角度为活性增强的负载型催化剂的设计提供了新的思路，并且可能适用于其他可还原氧化物负载的金属催化剂。