Carbon-supported ultra-high loading Pt nanoparticle catalyst by controlled overgrowth of Pt: Improvement of Pt utilization leads to enhanced direct methanol fuel cell performance

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• 作者：Dae Jong You^a ; Kyungjung Kwon^b ; ^{kfromberk@gmail.com} ; Sang Hoon Joo^c ; Jin Hoe Kim^d ; Ji Man Kim^d ; ^e ; Chanho Pak^a ; ^{chanho.pak@samsung.com} ; Hyuk Chang^a
• 关键词：Pt nanoparticle ; Ultra-high metal loading ; Multi-step reduction ; Catalyst utilization ; Direct methanol fuel cell
• 刊名：International Journal of Hydrogen Energy
• 出版年：2012
• 期刊代码：42_03603199
• 类别：ch
• 出版时间：April, 2012
• 卷：37
• 期：8
• 页码：6880-6885
• 文件大小：913 K

摘要

Carbon-supported Pt nanoparticle catalysts with ultra-high loading up to 85%are prepared by multi-step reduction (Pt/C-nR), in which additional Pt precursors are reduced upon a preformed Pt/C catalyst (Pt/C-1R). Transmission electron microscopy images show that the Pt/C-nR catalysts are composed of multilayers of Pt nanoparticles. The multiply stacked morphology in the Pt/C-nR catalysts may originate from the local overgrowth of additionally reduced Pt nanoparticles on the pre-existing Pt nanoparticles in the Pt/C-1R catalyst rather than conformal growth. The electrochemical characterizations by cyclic voltammograms in HClO₄ solution reveal that Pt/C-2R catalyst exhibits an increased Pt utilization over the Pt/C-1R catalyst of the same Pt loading on the carbon support where a significant portion of catalytically active surfaces are buried within micropores of carbons. Furthermore, a direct methanol fuel cell (DMFC) single cell employing Pt/C-2R catalyst exhibits an enhanced DMFC performance compared to a single cell using the Pt/C-1R catalyst, demonstrating the importance of morphological control of Pt nanoparticles that can improve the catalyst utilization.