Coordinatively unsaturated aluminum anchored Ru cluster for catalytic hydrogenation of benzene

The design and synthesis of highly dispersed metal catalyst have attracted increasing attention, and it is still challenging to generate stable metal clusters with high metal loadings. Support plays a crucial role in determining particle morphology and dispersion. Herein, we demonstrate a strategy for synthesizing an amorphous alumina with 62% Al-penta(3+) sites (penta-coordinated Al3+) via solution combustion synthesis. It provides sufficient oxygen defects to anchor Ru species. For benzene hydrogenation reaction, the catalyst displays the high TOF (18833 h(-1)), which is about 2 times higher than that of catalysts supported on commercial alumina. The DFT calculations also confirm that the high catalytic performance is closely correlated with the special configuration of Ru active sites over coordinatively unsaturated alumina. The penta-coordinated Al3+ was also applied to prepare Pd catalyst with high dispersion. This work provides a superior support which possesses abundant Al-penta(3+) sites and affords a possibility for the generation of high and stable dispersion for the preparation of supported metal catalysts. (C) 2021 Elsevier Inc. All rights reserved.