Bottom‐up Design of High‐Performance Pt Electrocatalysts Supported on Carbon Nanotubes with Homogeneous Ionomer Distribution. Issue 17 (7th August 2017)

• Record Type: Journal Article
• Authors: Yang, Zehui; Li, Jing; Ling, Ying; Zhang, Quan; Yu, Xinxin; Cai, Weiwei
• Is Part Of: ChemCatChem. Volume 9:Issue 17(2017)
• Page Start: 3307
• Page End: 3313
• Publication Date: 2017-08-07
• Subjects: bottom-up design -- electrocatalysis -- fuel cells -- nanotubes -- platinum; Catalysis -- Periodicals; 541.39505
• DOI: 10.1002/cctc.201700587
• Languages: English
• ISSNs: 1867-3880

Abstract

Abstract: Homogeneous ionomer networks are primarily important for the enhancement of fuel cell performance. Here, we report a bottom‐up design of platinum (Pt) electrocatalysts with homogeneous ionomer layers, in which Pt nanoparticles are deposited on carbon nanotubes (CNTs) after sequentially wrapping with polybenzimidazole (PBI) and end‐capped hyperbranched sulfonated macromolecules (E‐HBM) (CNT/PBI/E‐HBM/Pt). E‐HBM, which are proton conductive macromolecules, are homogeneously coated on CNTs owing to the base–acid interaction between PBI and E‐HBM. The durability and oxygen reduction reaction (ORR) results indicate that CNT/PBI/E‐HBM/Pt exhibits higher Pt stability and ORR activity compared with the electrocatalyst without E‐BHM. The Nafion ionomer‐free membrane electrode assembly (MEA) fabricated from CNT/PBI/E‐HBM/Pt (704 mW cm −2 ) shows higher power density than the MEA from CNT/PBI/Pt with Nafion ionomer (30 wt %, 603 mW cm −2 ) owing to the unique bottom‐up design resulting in high Pt utilization efficiency. Abstract : Better without : A Pt electrocatalyst with homogeneous ionomer networks is fabricated through a bottom‐up approach, in which proton conductive macromolecules, E‐HBM, were coated on carbon nanotubes (CNTs) before Pt deposition assisted by polybenzimidazole (PBI) through acid–base interactions. The CNT/PBI/E‐HBM/Pt catalyst showed higher Pt stability and superior oxygen reduction activity and fuel cell performance than commercial electrocatalysts.