Mapping the Nucleation of H2 Bubbles on Polycrystalline Pt via Scanning Electrochemical Cell Microscopy

• DOI: 10.1021/acs.jpclett.9b01414
• Publication Date: 2019-06-26T18:13:50Z
• Authors: Yufei Wang; Emma Gordon; Hang Ren
• Keywords: 01 natural sciences; 0104 chemical sciences

Electrochemically generated bubbles are gaining increasing attention for their detrimental effects on the efficiency of electrocatalysis involving gaseous products, including hydrogen evolution reaction (HER). As a model system, bubble nucleation is also fundamental interest. Herein, we report single-entity approach to map H2 polycrystalline Pt via scanning electrochemical cell microscopy (SECCM). Individual (∼500 nm radius) HER in attoliter an SECCM instrument. Nucleation and growth results characteristic voltammetric peak current, which related concentration activation energy required nucleation. By mapping local voltammograms at various locations Pt, found heterogeneous distribution energetics surface. However, such heterogeneity not correlated with crystal grains or grain boundaries.