Facile preparation of a methanol catalyst with ultra-high voltage efficiency and super-durability: Pt pollution introduction by composite electrodeposition

• Published in: Journal of materials chemistry. A, Materials for energy and sustainability Vol. 11; no. 14; pp. 7556 - 7563
• Main Authors: Lei, Hao, Cui, Mangwei, Li, Wenzheng, Huang, Yan
• Format: Journal Article
• Language: English
• Published: Cambridge Royal Society of Chemistry 04.04.2023
• Subjects: Catalysts; Chemical reduction; Chemical synthesis; Composite materials; Durability; Electrodeposition; Fuel cells; Fuel technology; High voltage; Methanol; Noble metals; Oxidation; Oxygen reduction reactions; Pollution
• ISSN: 2050-7488; 2050-7496
• DOI: 10.1039/d2ta09655b

Noble metal catalysts are still the best methanol oxidation reaction (MOR) catalysts for direct methanol fuel cells nowadays, because the MOR onset potential of non-noble metal-based catalysts is much higher than that of Pt (usually greater than 1.35 V vs. RHE), so that the potential of the MOR is even higher than that of the oxygen reduction reaction and cannot form a cell. Here, we develop a high-performance non-noble-metal based (CoSn) MOR catalyst with a small amount (3.2 wt%) of Pt, which exhibits overpotential even lower than that of Pt/C (260 mV lower), unparalleled stability (retains 610 mA mg Pt −1 after chronoamperometry testing for 28 h, the best value for methanol oxidation reported to date) and high methanol oxidation activity (3680 mA mg Pt −1 ). We synthesize this CoSn-Pt catalyst by innovatively utilizing a Pt plate as a counter electrode (which is always avoided to prevent potential pollution of Pt in the past) to realize composite electrodeposition in a deep eutectic solvent. We innovatively develop a high-performance MOR catalyst with small amounts (3.2 wt%) of Pt by composite electrodeposition using a Pt plate as a counter electrode. The material exhibits ultra-high voltage efficiency and unparalleled stability.