Synthesis, Characterization and Catalytic Activity of Binary PtMn/C Alloy Catalysts towards Ethanol Oxidation

Abstract

Binary PtMn/C alloy catalysts with various atomic ratios (60-90 atomic% Mn) were synthesized and tested for the activity toward ethanol oxidation. The synthesized catalysts were characterized by energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). XRD studies indicate that a Pt-Mn alloy has formed in all cases. PtMn(19:81)/C and PtMn(10:90)/C exhibited the highest activity toward ethanol oxidation compared to PtMn(39:61)/C and Pt/C. XPS analysis indicates that highest activity occurs for alloys with similar surface and bulk Mn contents.

Improving the Ethanol Oxidation Activity of Pt-Mn Alloys through the Use of Additives during Deposition

“…The impregnation method was used to prepare Pt-Mn/C catalysts with a composition of Pt0.25Mn0.75, similar to that previously published [4]. The metal precursors were H2PtCl6·H2O (Aldrich, Oakville, ON, Canada) and MnCl2·4H2O (Aldrich, Oakville, ON, Canada).…”

“…Problems associated with the costs and efficiency of fuel cells are a great barrier for industrial and consumer applications [1][2][3][4]. Direct alcohol fuel cells (DAFCs) are one of the most promising candidates for portable power applications in electronic devices and vehicles [4].…”

“…Direct alcohol fuel cells (DAFCs) are one of the most promising candidates for portable power applications in electronic devices and vehicles [4]. The cost and performance of the DAFCs are mainly controlled by the catalysts used at each electrode.…”

“…Pt is the most commonly utilized electrocatalyst, which is quite expensive [3]. Furthermore, strongly adsorbing species, such as CO, which are formed during the alcohol oxidation process on pure Pt particles, result in severe activity and efficiency losses [4,5]. The development of Pt alloy catalysts offers the potential of greater tolerance to poisoning and significant cost reduction.…”

Addition of iron oxide to Pt-based catalyst to enhance the catalytic activity of ethanol electrooxidation

“…However, Pt alone does not display good catalytic activity toward the oxidation of ethanol, so the addition of other metals that can act as co-catalyst is necessary [7,[11][12][13][14][15][16][17][18][19][20]. Over the years, a range of binary and ternary Pt-based catalysts have been evaluated [16,[21][22][23][24][25], mainly PtSn [26][27][28][29][30] and PtRu [31][32][33][34]. The proposed reaction mechanism for the electrooxidation of ethanol at a Pt-M catalyst is based on different techniques such, Differential Electrochemical Mass Spectrometry (DEMS) [33,[35][36][37][38], in situ Fourier-Transform Infrared Spectroscopy…”