Next generation heterogeneous catalysis: a conceptual design of single nanoparticle reactor
Sheng Dai1, Jyh-Pin Chou2, Kuan-Wen Wang3, Alice Hu2, Tsan-Yao Chen4,5*
1School of Chemistry & Molecular Engineering, East China University of Science and Technology, Shanghai, China
2Department of mechanical and biomedical engineering, City University of Hong Kong, Kowloon, Hong Kong
3Institute of Materials Science and Engineering, National Central University, Taoyuan, Taiwan
4Department of Engineering and System Science, National Tsing Hua University, Hsinchu, Taiwan
5Institute of Nuclear Engineering and Science, National Tsing Hua University, Hsinchu, Taiwan
* Presenter:Tsan-Yao Chen,
Scientists had been looking for the optimum design of heterogeneous catalysts with capability to facilitate the chemical reaction kinetics. However, with the confinement effects of composition and configurations in state-of-the-art fabrication methodologies, uniformity control on aforementioned factors are generally employed. However, any of the existing design result in uniform local chemical environment in catalyst surface. In this event, the selectivity toward intermediate steps of chemical reaction are suppressed, therefore, the performance of catalyst is limited. Surface decoration with atomic scaled clusters in different compositions rationalizes design of nanocatalysts as a single nanoparticle reactor. Such a design enables the interaction between atomic clusters in different intermediate steps. Those interactions simultaneously facilitate the reaction kinetics of all intermediate steps, as a result, leading to a quantum leap of catalytic performance of chemical reaction with a few nanometer regime. In this study, we demonstrate that the dimension of the surface decoration can be manipulated down to atomic scale. Apart from using noble metals, atomic scaled Pt clusters were employed to improve the oxygen reduction reaction performance of catalysts. Those clusters are decorated in surface defect regions of Cocore-Pdshell (Co-Pd) nanoparticles by using self-aligned nanocrystal growth followed by atomic quench with strong reduction agent. They localize electrons from neighboring atoms and boost activity of Co-Pd NP in ORR. With a proper reaction time and loading control, the Pt cluster decorated Co - Pd nanoparticles enhance its mass activity by 340 times as compared to that of commercial Pt catalysts in an alkaline electrolyte of 1.0M KOH.

Keywords: Atomic Clusters, oxygen reduction reaction , Fuel cell, single nanoparticle reactor