(58a) Optimize Activity and Durability of Multimetallic Electrocatalysts By Tuning the Nanostructure

Chemical-electrical energy conversion and storage are greatly attractive for the development of sustainable energy. Among the chemical-electrical energy conversion devices, polymer electrolyte membrane fuel cell (PEMFC) is one promising technology for portable applications, from as small as portable electronics, to as large as automobiles. One of the key components for PEMFCs is the electrocatalyst. Development of high-performance electrocatalyst nanomaterials relies on tuning material structures at nanoscale. This is in particular manifested in the design of electrocatalysts demanding both high activity and durability. Through solution-phase-synthesis, high quality nanocrystals are prepared at various morphologies (shape-controlled) and compositions (composition-controlled). The nanostructure (i.e. selective exposing specific low-index surface, controlling core-shell structure, and etc.) of nanocrystals are also carefully tuned. Using well-controlled nanomaterials, we explore the correlation between nanostructure and activity (and/or durability), and thus optimize the balance of activity and durability. Herein, a group of high performance electrocatalysts are developed for various electrocatalytic processes, including oxygen reduction reaction (ORR) and hydrogen evolution reaction (HER). It is well-demonstrated that the careful manipulation of nanostructure of electrocatalysts is crucial to improve the activity and durability.