Chem Catalysis Pub Date : 2022-06-01 , DOI: 10.1016/j.checat.2022.05.013 Shuo Liu , Chaochao Dun , Mihir Shah , Junjie Chen , Satyarit Rao , Jilun Wei , Eleni A. Kyriakidou , Jeffrey J. Urban , Mark T. Swihart
Commercial dry reforming of methane (DRM) is limited by catalyst deactivation through metal sintering and coking. New catalyst synthesis methods are needed to overcome such challenges. Here, we report a unique flame aerosol synthesis and exsolution method for producing hollow Ni-Zr oxide nanoshells as a highly stable and efficient DRM catalyst. This process incorporates immiscible elements into single-phase hollow nanoshells by rapid particle formation and quenching. Ni nanoparticles are then uniformly exsolved from the metastable solid solution to provide strong metal-support interactions that limit metal sintering. Rapid synthesis under reducing conditions produces oxygen vacancies in ZrO2 that favor carbon removal during the DRM reaction. As a result, our catalyst maintained 98% CH4 conversion for more than 500 h, without sintering or coking, dramatically outperforming conventional catalysts. This method of metastable solid solution nanoshell formation followed by active site exsolution could provide durable catalysts for many high-temperature reactions.
中文翻译:
通过火焰合成和 Ni 脱溶生产用于甲烷干重整的超稳定 Ni-ZrO2 纳米壳催化剂
甲烷的商业干法重整 (DRM) 受到金属烧结和焦化催化剂失活的限制。需要新的催化剂合成方法来克服这些挑战。在这里,我们报告了一种独特的火焰气溶胶合成和脱溶方法,用于生产空心 Ni-Zr 氧化物纳米壳作为高度稳定和高效的 DRM 催化剂。该过程通过快速颗粒形成和淬火将不混溶的元素结合到单相中空纳米壳中。然后,Ni 纳米颗粒从亚稳态固溶体中均匀溶解,以提供限制金属烧结的强金属-载体相互作用。在还原条件下的快速合成在 ZrO 2中产生氧空位,有利于 DRM 反应期间的碳去除。结果,我们的催化剂保持了 98% 的 CH 4转化时间超过 500 小时,无需烧结或结焦,显着优于传统催化剂。这种亚稳态固溶体纳米壳形成然后活性位点外溶的方法可以为许多高温反应提供耐用的催化剂。