Shape Reconstruction from Commercial Pt/C to High-Index Pt/C for Advanced Electrocatalysts
Lifei Ji, Meng‐Wei Lin, Wei Yan, Yuchen Cai, Guang Li, Jinhong Zheng, Shiyuan Zhou, Zheng Huang, Hong‐Gang Liao, Haixin Lin, Xiao Chi, Binwei Zhang, Yanxia Jiang, Shi‐Gang Sun
Abstract
Pt-based materials with high-index facets (HIFs) are highly regarded as efficient electrocatalysts, because of their abundant active step sites. Nevertheless, it is still a significant challenge to control the size to match that of commercial Pt/C (∼4 nm). Here, Pt THH(210)/C with an average size of ∼6 nm is successfully synthesized by employing bismuth (Bi) as a structural modulator to reshape commercial Pt/C. In-situ Fourier transform infrared spectroscopy (FTIRS) with formic acid and CO probes demonstrate that Bi is effectively removed from tetrahexahedral (THH) PtBi/C. The Pt THH(210)/C possesses a high density of stepped atoms ( d step ), exhibiting a great area activity of 1.232 mA/cm 2 at 0.571 V toward ethanol oxidation, which is three times than that of commercial Pt/C (0.464 mA/cm 2 at 0.594 V). Furthermore, a descriptor based on the charge density for oxygen adsorption was proposed to measure d step on HIF-Pt catalysts.