Coordination-in-pipe engineering of Pt-based intermetallic compounds with nanometer to angstrom precision

Abstract

The simultaneous regulation of particle size, surface coordinated environment and composition for Pt-based intermetallic compound (Pt-IMC) nanoparticles to manipulate their reactivity for energy storage is of great importance. Herein, we report a general synthetic method for Pt-IMCs using SBA-15 for coordination-in-pipe engineering. The particle size can be regulated to 3–9 nm by carrying out the coordination in pipes with different diameters and the coordination number of the interface metal atoms can be adjusted by altering the N source. Moreover, this strategy can also be expanded to the synthesis of Pt-IMCs with the majority of fourth period transition metals (Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn). The Pt₃Co IMC using 1,10-phenanthroline as the nitrogen source (Pt₃Co@CN) shows the highest catalytic performance in the methanol oxidation reaction (MOR; 2.19 A mg_Pt⁻¹) among the investigated nitrogen sources. The high chemical states of surface Pt and Co, affected by the nitrogen coordination number at the angstrom scale, facilitate electron accumulation on active sites, reduce the activation energy of the rate-determining step and enhance the catalytic performance of Pt-IMCs in the MOR.