News Release

Ru-Co single-atom alloy catalysts for efficient amination of alcohols

Peer-Reviewed Publication

Dalian Institute of Chemical Physics, Chinese Academy Sciences

Figure Abstract

image: 

Ru-Co/ZrO2 single-atom alloy catalyst was developed for alcohol amination, which exhibited satisfactory yields to primary amines for a broad scope of substrates. The synergistic effect between Ru and Co was demonstrated by the significantly higher turnover rate and yield to primary amine than those on Co/ZrO2 and Ru/ZrO2. This study opens a new avenue to the design of low-cost and efficient catalysts for alcohol amination.

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Credit: Chinese Journal of Catalysis

Primary amines are extensively used in the manufacture of pharmaceuticals, agrochemicals, and material science. Among various reported methods to access primary amines, the direct amination of alcohols with ammonia is most promising and environmentally benign since alcohols can be derived from renewable biomass and the sole byproduct is water. While a large number of catalyst systems have been developed for alcohol amination, challenges remain to be addressed such as the low selectivity to primary amines at high alcohol conversions, the high cost of noble metals and the low efficiency of non-noble metals, as well as the harsh reaction conditions. To tackle these challenges, it is highly desired to develop novel catalyst materials which can substantially save the use of expensive noble metals meanwhile exhibit high activity and selectivity to primary amines under milder reaction conditions.

 

Recently, a research team led by Prof. Tao Zhang & Prof. Aiqin Wang (Dalian Institute of Chemical Physics, Chinese Academy of Sciences (CAS)) designed a Ru-Co single-atom alloy (SAA) catalyst for the amination of alcohols. The SAA structure was identified as the real active site leading to excellent performance. The result has been published in Chinese Journal of Catalysis (DOI: 10.1016/S1872-2067(25)64714-0)

 

The Ru-Co alloy catalysts were prepared by the incipient wetness impregnation method. Compared to monometallic Co and Ru based catalysts which showed only minor conversions of alcohols, all the bimetallic Ru-Co catalysts gave rise to markedly increased activities. Besides, the remarkable enhancement in the activity took place only at an extremely dilute Ru concentration (Ru/Co ≤ 30), above which the promotional effect of Ru was alleviated. Calculation of the turnover rate (TOR) based on the initial conversion revealed that the TOR over the best-performance Ru1-Co30/ZrO2 catalyst was 8.4 times higher (11.8 h-1 vs 1.4 h-1) than that over the Co/ZrO2 catalyst. The substrate scope and reusability tests of catalyst showed that the catalyst could be applied to the amination of a broad scope of alcohols with satisfactory yields of primary amines and exhibited excellent stability, showing great potential for practical applications.

 

The structural characterizations were performed on the alloy catalysts, which demonstrated that the SAA structure was formed when the Ru/Co molar ratio was less than 1/30, and the Ru-Co SAA structure was responsible for the activity. The alloyed Ru could greatly promote the reduction of Co and strengthened the interaction with hydrogen molecules, which would be favorable for the alcohol dehydrogenation which has been recognized as the rate-determining step of alcohol amination. Most importantly, the Ru-Co alloy mitigated the over-strong adsorption of intermediate aldehyde on Co, which was crucial for improving catalytic performance. This study provides new insights into the mechanism for synergy in the single-atom alloy catalysts and opens a new avenue to the design of low-cost and efficient catalysts for alcohols amination.

The results were published in Chinese Journal of Catalysis (DOI: 10.1016/S1872-2067(25)64714-0

About the Journal

Chinese Journal of Catalysis is co-sponsored by Dalian Institute of Chemical Physics, Chinese Academy of Sciences and Chinese Chemical Society, and it is currently published by Elsevier group. This monthly journal publishes in English timely contributions of original and rigorously reviewed manuscripts covering all areas of catalysis. The journal publishes Reviews, Accounts, Communications, Articles, Highlights, Perspectives, and Viewpoints of highly scientific values that help understanding and defining of new concepts in both fundamental issues and practical applications of catalysis. Chinese Journal of Catalysis ranks among the top one journals in Applied Chemistry with a current SCI impact factor of 17.7. The Editors-in-Chief are Profs. Can Li and Tao Zhang.

At Elsevier http://www.journals.elsevier.com/chinese-journal-of-catalysis

Manuscript submission https://mc03.manuscriptcentral.com/cjcatal


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