Enhancement of Durability and Electrocatalytic Activity of Pt/C via CTAB-Modified Ultrathin Mesoporous Silica Coating for Methanol Oxidation

摘要

An ultrathin mesoporous silica layer was directly coated onto Pt/C (Pt/C@mSiO(2)) using a cetyltrimethyl ammonium bromide (CTAB)-modified Stober method without introducing an intermediate layer. The stability of the synthesised Pt/ C@mSiO(2) was evaluated by the accelerated potential cycling test (APCT). The electrochemically active surface area (ECSA) of the Pt/C@mSiO(2) remained at 90% while the ECSA of the Pt/C decreased to 51% after APCT. Transmission electron microscopy images of the Pt/C and the Pt/C@mSiO(2) before and after APCT suggest the silica coating effectively suppressed Pt aggregation. Furthermore, the Pt/C@mSiO(2) exhibited higher electrocatalytic activity for methanol oxidation reaction than Pt/C.