Ternary dendritic nanowires as highly active and stable multifunctional electrocatalysts

Abstract

Multimetallic nanocatalysts with a controlled structure can provide enhanced catalytic activity and durability by exploiting electronic, geometric, and strain effects. Herein, we report the synthesis of a novel ternary nanocatalyst based on Mo doped PtNi dendritic nanowires (Mo-PtNi DNW) and its bifunctional application in the methanol oxidation reaction (MOR) at the anode and the oxygen reduction reaction (ORR) at the cathode for direct methanol fuel cells. An unprecedented Mo-PtNi DNW structure can combine multiple structural attributes of the 1D nanowire morphology and dendritic surfaces. In the MOR, Mo-PtNi DNW exhibits superior activity to Pt/C and Mo doped Pt dendritic nanowires (Mo-Pt DNW), and excellent durability. Furthermore, Mo-PtNi DNW demonstrates excellent activity and durability for the ORR. This work highlights the important role of compositional and structural control in nanocatalysts for boosting catalytic performances.

A simple electrochemical method for conversion of Pt wires to Pt concave icosahedra and nanocubes on carbon paper for electrocatalytic hydrogen evolution

“…1d) of a single Pt concave polyhedron displays the lattice fringes with interplanar spacing of about 0.134 nm along the [111] zone axis (Fig. 1d, inset), corresponding to the (220) plane of face-centered-cubic (fcc) Pt [36]. The characteristic five-fold symmetry axe of Pt concave icosahedron with the exposed (111) plane is observed from a high-angle annular dark-field scanning TEM (HAADF-STEM) image (Fig.…”

Metal‐Based Electrocatalysts for Methanol Electro‐Oxidation: Progress, Opportunities, and Challenges

“…For instance, Mo-doped PtNi dendritic nanowires (Mo-PtNi DNW; Figure 13a,b) can combine multiple structural attributes and exhibit superior MOR activity and excellent durability to Pt/C catalysts (Figure 13c,d). [107] The Mo-PtNi DNW/C catalyst showed higher initial maximum [40] (Figure 13e,f). [42] Different from above-mentioned Mo-PtNi DNW catalysts, the ECSA of the dendritic Cu 4 Pt 2 Pd 2 nanocomposite possessed an ECSA of 88.3 m 2 g −1 , much higher than commercial Pt black (9.4 m 2 g −1 ) and Pd black (17.0 m 2 g −1 ).…”

“…Kim and co-workers prepared the PdRu, PdSn, and PdIr binary nanoparticle catalysts (≈3.5 ± 0.2 nm) by using a borohydride reduction method, which were dispersed on reduced graphene oxide (RGO) at a 60 wt% mass loading to deliver Reproduced with permission. [107] Copyright 2016, The Royal Society of Chemistry. e,f) TEM and HRTEM images of dendritic Cu 4 Pt 2 Pd 2 nanocomposites with the corresponding SAED pattern.…”

Solvothermal Synthesis of Nanostructured PtnNi Tetrahedrons with Enhanced Platinum Utilization and Activity toward Oxygen Reduction Electrocatalysis

“…For instance, the Pt 3 Ni­(111)-derived Pt surface exhibited an exceptionally high IA Pt for ORR, i.e., 10- and 90-fold higher than those of Pt(111) and commercial Pt/C, respectively . Over the past decade, advancement in the synthesis of Pt-containing alloy nanostructures has led to generation of a variety of Pt-based nanoalloys with well-controlled compositions and morphologies (e.g., truncated octahedrons, octahedrons, , icosahedrons, mesostructured thin films, dendritic nanowires, , octahedral Pd@Pt 1.8 Ni core@shell nanocrystals, nanoframes, etc.). Among these various nanoalloys, octahedrons and icosahedrons would be always the desirable morphologies that can easily lead to Pt alloy nanostructures enclosed with Pt(111) planes for catalyzing ORR, which remains a topic of great interest. ,, …”