Epitaxial Growth of Au–Pt–Ni Nanorods for Direct High Selectivity H₂O₂ Production

Abstract

Au-Ni core-shell nanorods (NRs) and Au-Pt-Ni core-sandwich-shell NRs are synthesized and exhibit high activity for selective H O production via direct oxygen reduction. The epitaxial growth with coherent lattice fringes allow for the tuning of the oxygen reduction pathway. Moreover, a selectivity of 95% and mass activity of 192.9 A g are achieved using Au-Pt-Ni NRs at 150 mV overpotential.

2 D Hybrid of Ni‐LDH Chips on Carbon Nanosheets as Cathode of Zinc–Air Battery for Electrocatalytic Conversion of O2 into H2O2

“…The mass activity of Ni‐LDH/CNSs was approximately 22.2 A g −1 under limiting diffusion current platform potential at approximately 0.45 V (vs. RHE), which was approximate 1.8 times and 4.5 times higher than those of pristine Ni‐LDH nanosheets and commercial graphene oxide (GO) catalysts, respectively, as well as significantly better than that of CNSs. The mass activity was also comparable to the values of noble metals reported previously . Figure d records the H 2 O 2 selectivity in the potential range of 0.65–0.3 V. The selectivity was promoted up to 87 % for Ni‐LDH C/CNSs, and the number of transferred electrons ( n ) at 0.45 V decreased to approximately 2.24, which indicated a predominately two‐electron pathway ORR catalyzed by Ni‐LDH C/CNSs.…”

“…To predict and screen the catalyst candidates, a volcano relationship using the *HOO (* indicates an adsorbed species) binding energy as descriptor was recently identified as a powerful tool . With this method, a variety of noble‐metal‐based alloyed materials have been identified as suitable electrocatalysts for suppressing the 4 e ORR process; nevertheless, there remains great potential to develop new precious‐metal‐free electrocatalysts for further improving the associated catalytic performance and lowering the cost.…”

Surface Oxidation of AuNi Heterodimers to Achieve High Activities toward Hydrogen/Oxygen Evolution and Oxygen Reduction Reactions

“…The (111) facets of Au can stabilize the formation of H 2 O 2, and this was also confirmed by our experiments (Figure S29, Supporting Information). Previously, Au–Ni core–shell structures have shown high selectivity toward the formation of H 2 O 2, however, the mechanism has also not been unequivocally determined. Thus, we used DFT calculations to illustrate the possible mechanism (Figure c).…”

“…If Au and Ni are uniformly dispersed in the structure, a 4e − reduction mechanism can be obtained . If Ni is exposed at the surface, a 2e − reduction mechanism has been identified, and adding Pt in the shell could further enhance the selectivity of the 2e − reduction mechanism . However, when a Pt shell is formed outside AuNi materials, both Au@Ni@Pt and Ni@Au@Pt with proper compositions could all bring about higher activity and durability comparing to that of pure Pt materials.…”

Au–Cu–Ag Nanorods Synthesized by Seed‐Mediated Coreduction and Their Optical Properties

“…Pd–Au bimetallic nanoparticles have the plasmonic‐induced enhancement of electrocatalytic activity for ethanol oxidation . Compared to bimetallic nanoparticles, trimetallic nanosystems offer new functionalities and additional parameters to tailor the physical and chemical properties of nanoparticles . In terms of plasmonic nanomaterials, trimetallic Au–Cu–Ag nanostructures are the most attractive because Au, Ag, and Cu can all support localized surface plasmon resonance in the visible wavelength region and act as catalytic active sites for driving chemical reaction .…”