Determination of the electrochemically active surface area by CO and hydrogen of PtSnRuTa/C-based electrocatalysts and their relationship with catalytic activity against alcohol oxidation

• Published in: Chemical papers Vol. 76; no. 7; pp. 4597 - 4613
• Main Authors: Queiroz, Maria Aparecida Ribeiro, Vasconcellos, Maria de Lourdes Soprani, Ribeiro, Marcos Antônio, Luz, Priscila Paiva, de Moura Souza, Felipe, dos Santos, Mauro Coelho, Guimarães, Marco C. C., Salgado, José Ricardo Cezar, Pedicini, Rolando, Ribeiro, Josimar
• Format: Journal Article
• Language: English
• Published: Warsaw Versita 01.07.2022; Springer Nature B.V
• Subjects: Alcohol; Biochemistry; Biotechnology; Carbon monoxide; Catalytic activity; Chemistry; Chemistry and Materials Science; Chemistry/Food Science; Cubic lattice; Electrocatalysts; Ethanol; Ethylene glycol; Fuel cells; Glycerol; Industrial Chemistry/Chemical Engineering; Materials Science; Medicinal Chemistry; Methanol; Nanoalloys; Nanoparticles; Original Paper; Oxidation; Ruthenium; Surface area; Tantalum; Voltammetry; Electrocatalyst; Tantalum; Electrochemically active surface area; Platinum; Direct alcohol fuel cells
• ISSN: 0366-6352; 1336-9075; 2585-7290
• DOI: 10.1007/s11696-022-02191-3

This work studies the influence of the addition of tantalum to the ternary PtSnRu/C electrocatalysts on the oxidation of different alcohols: methanol, ethanol, ethylene glycol, and glycerol. The physical–chemical characterizations showed an increase in the lattice parameter of the fcc (face-centered cubic) structure of Pt due to the incorporation of Sn and/or Ta metals that evidence of alloy formation. The nanoparticles range from 3.8 to 9.8 nm and present a homogeneous distribution on carbon. CO stripping voltammetry measurements were used to obtain the electrochemically active surface area (ECSA) of electrocatalysts, which showed higher values for the quaternary electrocatalysts of composition Pt 24.8 Sn 5.0 Ru 1.0 Ta 7.7 /C (21.3 m 2 g Pt −1 ), Pt 8.1 Sn 1.3 Ru 1.2 Ta 1.0 /C (29.3 m 2 g Pt −1 ), and Pt 8.9 Sn 1.0 Ru 1.5 Ta 1.5 /C (39.4 m 2 g Pt −1 ). The Pt 8.9 Sn 1.0 Ru 1.5 Ta 1.5 /C electrocatalyst presented high peak currents, compared with the other electrocatalysts, using cyclic voltammetry for methanol, ethanol, ethylene glycol, and glycerol. In chronoamperometry on ethanol, ethylene glycol, and glycerol, the Pt 8.9 Sn 1.0 Ru 1.5 Ta 1.5 /C electrocatalyst showed higher currents (24, 18, and 19 A g Pt −1 , respectively) compared to the other electrocatalysts. The results showed that the addition of Ru and Ta on PtSn/C nanoparticles led to an increase in the ECSA values. It can be suggested that the presence of the quaternary electrocatalyst maximizes the electronic and bifunctional mechanism which are responsible to increase the electrocatalytic activity to the alcohol oxidation. In addition, the presence of Ru and Ta together with Sn on Pt/C nanoparticles was also related to increased stability, representing an alternative for use in direct alcohol fuel cells.