A perspective on the promoting effect of Ir and Au on Pd toward the ethanol oxidation reaction in alkaline media

Abstract

There remain great challenges in developing highly efficient electrocatalysts with both high activity and good stability for the ethanol oxidation reaction in alkaline media. Herein, two architectures of tri-metallic PdIrAu/C electrocatalysts are designed and the promoting effect of Au and Ir on Pd toward the ethanol oxidation reaction (EOR) in alkaline media is investigated in detail. On the one hand, the tri-metallic Pd₇Au₇Ir/C electrocatalyst with a solid solution alloy architecture is less active relative to Pd₇Ir/C and Pd/C while the stabilizing effect of Au leads to both a higher activity and a lower degradation percentage after 3000 cycles of the accelerated degradation test (ADT) on Pd₇Au₇Ir/C than those on Pd₇Ir/C. On the other hand, the tri-metallic Pd₇Ir@(1/3Au)/C electrocatalyst with a near surface alloy architecture delivers a much higher activity with an improvement up to 50.4% compared to Pd₇Ir/C. It is speculated that for the tri-metallic Pd₇Ir@(1/3Au)/C electrocatalyst, certain Au atoms are well designed on surfaces to introduce an electronic modification, thus leading to an anti-poisoning effect and improving the EOR activity.

Keywords

fuel cells / catalysts / ethanol oxidation / alkaline media / solid solution alloy / near surface alloy

References

[1] Johansson T B, Kelly H, Reddy A K N, Williams R H. Renewable Energy: Sources for Fuels and Electricity. Washington: Island Press, 1993

[2] Chum H L, Overend R P. Biomass and renewable fuels. Fuel Processing Technology, 2001, 71(1–3): 187–195

[3] Vielstich W, Yokokawa H, Gasteiger H A. Handbook of Fuel Cells: Fundamentals Technology and Applications. Chichester: John Wiley & Sons, 2009

[4] Carrette L, Friedrich K A, Stimming U. Fuel cells– fundamentals and applications. Fuel Cells, 2001, 1(1): 5–39

[5] Li Y S, Feng Y, Sun X D, He Y L. A sodium-ion-conducting direct formate fuel cell: yielding electricity and base. Angewandte Chemie International Edition, 2017, 56(21): 5734–5737

[6] Yu E H, Wang X, Krewer U, Li L, Scott K. Direct oxidation alkaline fuel cells: from materials to systems. Energy & Environmental Science, 2012, 5(2): 5668–5680

[7] Zhao T S, Li Y S, Shen S Y. Anion-exchange membrane direct ethanol fuel cells: status and perspective. Frontiers of Energy and Power Engineering in China, 2010, 4(4): 443–458

[8] Li Y S, Sun X D, Feng Y. Hydroxide-self-feeding high-temperature alkaline direct formate fuel cells. ChemSusChem, 2017, 10(10): 2135–2139

[9] Yu E H, Krewer U, Scott K. Principles and materials aspects of direct alkaline alcohol fuel cells. Energies, 2010, 3(8): 1499–1528

[10] Bianchini C, Shen P K. Palladium-based electrocatalysts for alcohol oxidation in half cells and in direct alcohol fuel cells. Chemical Reviews, 2010, 41(3): 4183–4206

[11] Shen S Y, Zhao T S, Xu J B, Li Y S. Synthesis of PdNi catalysts for the oxidation of ethanol in alkaline direct ethanol fuel cells. Journal of Power Sources, 2010, 35(23): 12911–12917

[12] Zhang Z, Zhang C, Sun J, et al. Ultrafine nanoporous Pd Fe/Fe₃O₄ catalysts with doubly enhanced activities towards electro-oxidation of methanol and ethanol in alkaline media. Journal of Materials Chemistry A, Materials for Energy and Sustainability, 2013, 1(11): 3620–3628

[13] Mukherjee P, Roy P S, Mandal K, Bhattacharjee D, Dasgupta S, Bhattacharya S K. Improved catalysis of room temperature synthesized Pd-Cu alloy nanoparticles for anodic oxidation of ethanol in alkaline media. Electrochimica Acta, 2015, 154: 447–455

[14] Peng C, Hu Y, Liu M, Zheng Y. Hollow raspberry-like PdAg alloy nanospheres: high electrocatalytic activity for ethanol oxidation in alkaline media. Journal of Power Sources, 2015, 278: 69–75

[15] Ma L, He H, Hsu A, Chen R R. PdRu/C catalysts for ethanol oxidation in anion-exchange membrane direct ethanol fuel cells. Journal of Power Sources, 2013, 241(241): 696–702

[16] Maksić A, Smiljanić M, Miljanić Š, Rakočević Z, Štrbac S. Ethanol oxidation on Rh/Pd(poly) in alkaline solution. Electrochimica Acta, 2016, 209: 323–331

[17] Ma Y W, Zhang H M, Zhong H X, Xu T, Jin H, Geng X Y. High active PtAu/C catalyst with core–shell structure for oxygen reduction reaction. Catalysis Communications, 2010, 11(5): 434–437

[18] Zhang J L, Sasaki K, Sutter E, Adzic R R. Stabilization of platinum oxygen-reduction electrocatalysts using gold clusters. Science, 2007, 315(5809): 220–222

[19] Liang Z X, Zhao T S, Xu J B. Stabilization of the platinum–ruthenium electrocatalyst against the dissolution of ruthenium with the incorporation of gold. Journal of Power Sources, 2008, 185(1): 166–170

[20] Xu J B, Zhao T S, Shen S Y, Li Y S. Stabilization of the palladium electrocatalyst with alloyed gold for ethanol oxidation. International Journal of Hydrogen Energy, 2010, 35(13): 6490–6500

[21] Shen S Y, Guo Y G, Luo L X, Li F, Li L, Wei G H, Yin J W, Ke C C, Zhang J L. Comprehensive analysis on the highly active and stable PdAu/C electrocatalyst for ethanol oxidation reaction in alkaline media. Journal of Physical Chemistry C, 2018, 122(3): 1604–1611

[22] Shen S Y, Zhao T S, Xu J B. Carbon-supported bimetallic PdIr catalysts for ethanol oxidation in alkaline media. Electrochimica Acta, 2010, 55(28): 9179–9184

[23] Liang Y, Zhang H, Zhong H, Zhu X, Tian Z, Xu D, Yi B. Preparation and characterization of carbon-supported PtRuIr catalyst with excellent co-tolerant performance for proton-exchange membrane fuel cells. Journal of Catalysis, 2006, 238(2): 468–476

[24] Chen A, La Russa D J, Miller B. Effect of the iridium oxide thin film on the electrochemical activity of platinum nanoparticles. Langmuir, 2004, 20(22): 9695–9702

Acknowledgment

This work is supported by the National Natural Science Foundation of China (Grant Nos. 21503134 and 21533005), and the National Key Research and Development Program of China (Grant No. 2016YFB0101201).

RIGHTS & PERMISSIONS

2018 Higher Education Press and Springer-Verlag GmbH Germany, part of Springer Nature 2018