Platinum–Cobalt alloy networks for methanol oxidation electrocatalysis

Abstract

Three-dimensional (3D) platinum-cobalt alloy networks nanostructures with a high alloying degree were synthesized through a room temperature wet-chemical synthetic method using the K 2 PtCl 4 /K 3 Co(CN) 6 cyanogel as reaction precursor in the absence of surfactants and templates. The size, morphology and surface composition of platinum-cobalt alloy networks nanostructures were investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive spectrum (EDS), selected area electron diffraction (SAED), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The 3D backbone structure and double-metallic property of the K 2 PtCl 4 /K 3 Co(CN) 6 cyanogel are responsible for the 3D structure and the high alloying degree of the as-prepared products, respectively. Compared to the pure Pt nanoparticles, 3D platinum-cobalt alloy networks nanostructures exhibit superior electrocatalytic activity and stability for the methanol oxidation reaction (MOR), which is ascribed to their unique 3D structure and alloy properties.

Impact of Cu-Pt nanotubes with a high degree of alloying on electro-catalytic activity toward oxygen reduction reaction

“…The inert phases in the electrocatalyst might explain the lower electrocatalytic activity toward the ORR. To address this issue, some investigators [11] recently proposed a modified polyol synthesis strategy: by introducing surfactants or stabilizers to a conventional polyol system, the redox potentials of given metal ions can change through specific adsorption or coordination, reducing these ions simultaneously and, consequently, increasing the degree of alloying. While improvements to alloying degree are obtained to some extent, these additives, such as surfactants and stabilizers, are strongly adsorbed on the catalyst surface, often hindering or completely arresting the overall catalytic activity by eliminating the active surface.…”

“…While improvements to alloying degree are obtained to some extent, these additives, such as surfactants and stabilizers, are strongly adsorbed on the catalyst surface, often hindering or completely arresting the overall catalytic activity by eliminating the active surface. Fully the stabilizers without affecting catalyst performance is a challenging problem [11,12].…”

Efficiently cubic platinum-cobalt bimetallic nano-catalysts for use in low-cost dye-sensitized solar cells

“…3I À . The relatively higher catalytic activity of Pt 3 Co CE could be owing to that the cubic Pt 3 Co has modified Pt electronic structure [23][24][25], Pt-rich and Pt-skin nano-structure with homogeneous morphology. The working mechanism of Pt 3 Co and PtCo CEs could be that the 3d transition metal Co is an electron-rich metal, which could supply electrons for Pt catalyst and enhance the electron density to accelerate the redox reaction of I 3 À + 2e À !…”

“…In especial, Pt alloying with relatively cheap transition metals (i.e. Fe, Co, Ni, Ru) shows an enhanced catalytic activity due to the modification of the Pt electronic structure as well as the correlation of the ligand and strain effects [23][24][25], which is widely used as the efficient catalyst for the oxygen reduction and methanol oxidation in the area of fuel cells [23][24][25][26][27]. Recently, Chen et al firstly prepared highly active Pt-Ni bimetallic nano-crystals in the oleylamine, which exhibited excellent oxygen reduction reaction activity due to both the interior and exterior catalytic surfaces of this three-dimensional open-framework structure were composed of the nanosegregated Pt-skin structure [28].…”

Nanomagnetic CoPt truncated octahedrons: facile synthesis, superior electrocatalytic activity and stability for methanol oxidation

“…The selected-area electron diffraction pattern (SAED, shown in Fig. 1c) shows concentric rings with the index of (111), (200), (220), (311) and (222) [26,27]. The existence of shake up peaks of Co 2p is also caused by Co x+ 2p1/2.…”