Tesana Siriluck, Kennedy John V, Yip Alex C K, Golovko Vladimir B
School of Physical and Chemical Sciences, University of Canterbury, Christchurch 8041, New Zealand.
The MacDiarmid Institute for Advanced Materials and Nanotechnology, Wellington 6140, New Zealand.
Nanomaterials (Basel). 2023 Dec 12;13(24):3120. doi: 10.3390/nano13243120.
Preserving ultrasmall sizes of metal particles is a key challenge in the study of heterogeneous metal-based catalysis. Confining the ultrasmall metal clusters in a well-defined crystalline porous zeolite has emerged as a promising approach to stabilize these metal species. Successful encapsulation can be achieved by the addition of ligated metal complexes to zeolite synthesis gel before hydrothermal synthesis. However, controlling the metal particle size during post-reduction treatment remains a major challenge in this approach. Herein, an in situ incorporation strategy of pre-made atomically precise gold clusters within Na-LTA zeolite was established for the first time. With the assistance of mercaptosilane ligands, the gold clusters were successfully incorporated within the Na-LTA without premature precipitation and metal aggregation during the synthesis. We have demonstrated that the confinement of gold clusters within the zeolite framework offers high stability against sintering, leading to superior CO oxidation catalytic performance (up to 12 h at 30 °C, with a space velocity of 3000 mL g h).
保持金属颗粒的超小尺寸是多相金属基催化研究中的一个关键挑战。将超小金属簇限制在定义明确的结晶多孔沸石中已成为稳定这些金属物种的一种有前景的方法。在水热合成之前，通过向沸石合成凝胶中添加配位金属络合物可以实现成功的封装。然而，在这种方法中，后还原处理过程中控制金属颗粒大小仍然是一个主要挑战。在此，首次建立了在Na-LTA沸石中原位掺入预制的原子精确金簇的策略。在巯基硅烷配体的辅助下，金簇在合成过程中成功地掺入到Na-LTA中，而没有过早沉淀和金属聚集。我们已经证明，将金簇限制在沸石骨架内可提供高抗烧结稳定性，从而产生优异的CO氧化催化性能（在30°C下长达12小时，空速为3000 mL g h）。
