Highly Active PdNi/RGO/Polyoxometalate Nanocomposite Electrocatalyst for Alcohol Oxidation

Abstract

A PdNi/RGO/polyoxometalate nanocomposite has been successfully synthesized by a simple wet-chemical method. Characterizations such as transmission electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction analysis, and X-ray photoelectron spectroscopy are employed to verify the morphology, structure, and elemental composition of the as-prepared nanocomposite. Inspired by the fast-developing fuel cells, the electrochemical catalytic performance of the nanocomposite toward methanol and ethanol oxidation in alkaline media is further tested. Notably, the nanocomposite exhibits excellent catalytic activity and long-term stability toward alcohol electrooxidation compared with the PdNi/RGO and commercial Pd/C catalyst. Furthermore, the electrochemical results reveal that the prepared nanocomposite is attractive as a promising electrocatalyst for direct alcohol fuel cells, in which the phosphotungstic acid plays a crucial role in enhancing the electrocatalytic activities of the catalyst.

In situ electrochemical activation as a generic strategy for promoting the electrocatalytic hydrogen evolution reaction and alcohol electro-oxidation in alkaline medium

“…For both of the Au and Pd, three diffraction peaks correspond to the (1 1 1), (2 0 0), (2 2 0) planes are observed, which can be ascribed to the fcc structure of Au and Pd metals (JCPDS: 01-071-4073 for Au and 01-071-3757 for Pd). 30,31 Also, the diffraction peaks for the AuPd are attributed to the fcc structure of the metals. When compared to the monometallic nanoparticles, the peak position of bimetallic AuPd are very close to those of the Au rather than the Pd, indicating that the Au core is not signicantly strained.…”

One-pot facile simultaneous in situ synthesis of conductive Ag–polyaniline composites using Keggin and Preyssler-type phosphotungstates

“…35 Due to their inherent ability (vacant d molecular orbitals), HPAs can undergo fast, reversible, stepwise redox reactions under mild conditions while retaining their intact structures. 36 Highly negatively charged nature of HPAs is desirable for the molecular dispersion of HPAs on the positively charged backbone of a polymer. This alleviates the aggregation of AgNPs while silver ions are electronically embedded into the PAni matrix.…”

Nanocatalysts for Electrocatalytic Oxidation of Ethanol

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