Additive-Mediated Electrochemical Synthesis of Platelike Copper Crystals for Methanol Electrooxidation

Abstract

A room-temperature electrochemical approach to synthesizing anisotropic platelike copper microcrystals and nanocrystals in the presence of potassium bromide is presented. Morphological and elemental characterization was performed using SEM, TEM, and XRD to confirm the anisotropic morphology and crystal structure of the synthesized copper particles. A possible mechanism for explaining the anisotropic crystal growth is proposed on the basis of the preferential adsorption of bromide ions to selective crystal faces. The shape-dependent electrocatalytic property of copper particles is demonstrated by its enhanced catalytic activity for methanol oxidation. Further development of such anisotropic copper particles localized on an electrode surface will lead us to find a suitable alternative for noble metal-based electrocatalysts for the methanol oxidation reaction relevant to fuel cells.

Cu(III)-independent oxidation and sensing of glucose on multi-layer stacked copper nanoparticles

“…Besides the peaks assigned to graphite (G) and paraffin wax (W), one strong peak and two much weaker ones are present at 43. 5° [20]. The anisotropic laminated structure shown in Fig.…”

“…Porous Cu foams can be formed at very negative applied potentials, e.g., -6 V [6] or −4 V [19] vs. Ag/AgCl/ 3 M KCl, by the assistance of strong hydrogen evolution. An anisotropic plate-like morphology of Cu NPs was acquired at 0.06 V vs. Ag/AgCl/3 M KCl for methanol electro-oxidation [20]. At a potential of −0.175 V vs. Ag/AgCl/3 M KCl the obtained were the coarse grained copper clusters [21].…”

Highly Branched Metal Alloy Networks with Superior Activities for the Methanol Oxidation Reaction

“…Recently,ithas been reported that the {111} crystal planes of Cu and Ni have enhanced catalytic activity toward methanol oxidation. [14] As seen in Figure 1a nd the Supporting Information, Figure S1, the hierarchically structured Ni-Cu alloys composed of interconnected branches may allow the active {111} crystal plane to be fully exposed, which is favorable for the electrocatalytic oxidation reaction of methanol. Fort he XPS survey,p eaks in the full XPS spectrum indicate the existence of Cu, Ni, O, and Celements (Figure 1e;Supporting Information, Figure S6 a,c).…”

Highly Branched Metal Alloy Networks with Superior Activities for the Methanol Oxidation Reaction

“…Figure S7) revealed that the elemental distributions of Ni and Cu are uniform for all three samples,i ndicating that Ni and Cu are evenly distributed throughout the hierarchically structured Ni-Cu alloys.T he corresponding XRD spectrum (Supporting Information, Figure S3) confirmed the {111} planes of the hierarchically structured Ni-Cu alloys are preferentially oriented. [14] As seen in Figure 1a nd the Supporting Information, Figure S1, the hierarchically structured Ni-Cu alloys composed of interconnected branches may allow the active {111} crystal plane to be fully exposed, which is favorable for the electrocatalytic oxidation reaction of methanol. [14] As seen in Figure 1a nd the Supporting Information, Figure S1, the hierarchically structured Ni-Cu alloys composed of interconnected branches may allow the active {111} crystal plane to be fully exposed, which is favorable for the electrocatalytic oxidation reaction of methanol.…”