The research team led by Prof. LI Weixue from the University of Science and Technology of China (USTC) of the Chinese Academy of Sciences tackled key problems of the stability of supported nanocatalysts. They proposed the rational design of nanocatalysts and showed that the high-throughput screening of supports boosted the stability of nanocatalysts against sintering. This work was published in Science .
The stability of nanocatalysts determines the lab-to-fab translation of highly active nanocatalysts. However, unavoidable nanocatalyst deactivation caused by the thermal and/or chemical induced sintering makes it hard to realize satisfactory productivity, and the catalyst replacement or regeneration consequently brings high cost. Besides, there’s no widely recognized theory in the nanocatalyst field to mitigate sintering and thus expensive trial-and-error experimentations are required. These problems necessitate a theory to guide the design of ultrastable nanocatalysts.
Based on the first-principles neural network potential and kinetic simulations of metal-support pairs, researchers identified the appropriate metal–support interaction (MSI) descriptor by theoretical calculation.
By revealing the linear relationship between cohesive energy Ec and the adhesion energy Eadh, they found that too strong of an interaction would trigger Ostwald ripening, while too weak of an interaction would stimulate particle migration and coalescence (PMC). Both situations led to nanocatalyst deactivation, and the optimal MSI thus should be neither too strong nor too weak. This theory bridged the large gap between the sintering kinetics and the underlying MSI.
This is an extremely creative, thoughtful and in-depth and huge research contribution. I congratulate the authors in the tour-de-force,” Prof. Charles T. Campbell, honorary fellow of the Chinese Chemical Society (CCS), said. This is also the first theory proposed by Chinese scientists to guide the design of heterogeneous metal nanocatalysts. The rational design of nanocatalysts is of great value to nanoscience.
Prof. LI Weixue (left) and Dr. HU Sulei (right). (Image by LIU Yangfan and QIAN Jianhao)
Paper Link: http://www.science.org/doi/10.1126/science.abi9828
(Written by ZHANG Liying, edited by HOU Luyao, USTC News Center)