Plating Precious Metals on Nonprecious Metal Nanoparticles for Sustainable Electrocatalysts

摘要

src="http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/nalefd/2017/nalefd.2017.17.issue-6/acs.nanolett.7b00046/20170608/images/medium/nl-2017-00046d_0006.gif">Precious metals have broad applications in modern industry and renewable energy technologies. The high cost and limited availability of these materials, however, have caused a grand challenge for sustainability. Here, we report on the plating of a precious metal on nonprecious metal nanoparticles for the development of sustainable electrocatalysts. Cobalt/platinum core/shell (denoted as Co@Pt) nanoparticles were synthesized via seed-mediated growth. The Co seeds were first synthesized by thermal decomposition of cobalt carbonyl, and the Pt shell was overgrown in situ by adding platinum acetylacetonate (Pt(acac)₂). The galvanic replacement reaction between Co and the Pt precursor was successfully suppressed by taking advantage of CO (generated from the decomposition of cobalt carbonyl) as the stabilizing ligand and/or reducing agent. The obtained Co@Pt nanoparticles were further found to exhibit enhanced catalytic activity for the oxygen reduction reaction (ORR).