A Facile Method to Prepare Ultrafine Pd Nanoparticles Embedded into N-Doped Porous Carbon Nanosheets as Highly Efficient Electrocatalysts for Oxygen Reduction Reaction

Abstract

To explore cheap alternatives for platinum electrocatalysts, many strategies have been widely studied. And Pd is regarded as a ideal alternative catalyst due to its high stability and catalytic activity. In this work, we designed a facile method to prepare a highly efficient electrocatalyst in which ultrafine Pd nanoparticles are embedded into N-doped porous carbon nanosheets for oxygen reduction reaction (ORR) in alkaline and acid media. A series of products with different Pd quantities were in situ prepared in the absence of additional reductant and capping agents by varying the addition of PdCl2, while the morphology and the structural features of products through X-ray photoelectron spectroscopy (XPS), powder X-ray diffraction (XRD) and transmission electron microscopy (TEM) and BET measurements show that Pd nanoparticles are embedded into N-doped porous carbon nanosheets. Obviously, the sample of Pd-NCs-3 demonstrate the best electrocatalytic activity and remarkable long-term stability among the series, which is superior to that of commercial Pd/C and comparable to that of commercial Pt/C for ORR in alkaline and acid media. The results provides a novel strategy for the rational development of cheap alternatives for platinum electrocatalysts.

Recent Advances in Electrocatalysts for Proton Exchange Membrane Fuel Cells and Alkaline Membrane Fuel Cells

“…Porous carbon as support has several advantages compared to the traditional carbon black, such as larger surface area, confinement effect and accessible catalytic active sites. In recent years, a variety of porous carbons, such as porous carbon nanosheets, [269] 3D-graphene nanosheets (GNS), [270,271] ordered mesoporous carbon, [272] N-doped ordered mesoporous carbon nanospheres, [273] N-doped porous carbon nanosheets, [274] 3D porous N-doped carbon nanofiber, [275] and some organic frameworks derived porous carbons [178,256] have been explored as the support of Pd-based catalysts. For instance, Atanassov et al comparatively studied the ORR kinetics of Pd nanoparticles supported on 2D-GNS and 3D-GNS with micro and macro pores, respectively, and demonstrated that the porosity and pore size play important roles in enhancing the ORR performance and improving the O 2 mass transport in the high current density region.…”

Co/Co2P Nanoparticles Encapsulated within Hierarchically Porous Nitrogen, Phosphorus, Sulfur Co‐doped Carbon as Bifunctional Electrocatalysts for Rechargeable Zinc‐Air Batteries

“…[25,53,59,60] For instance, N doping can modulate the electron-neutrality of neighboring carbon atoms and improve the adsorption of O 2 species. [61,62] As reported in previous studies, [21,29] DFT calculations showed that the reverse electronegativity between P and S can lead to a unique electron-donor property in S-phosphide and the synergistic coupling effect between P, S and carbon, which facilitates ORR electrocatalysis. [2,3] Last but not least, the presence of metallic cobalt as a conductive electrocatalytic material provided more active sites, and Co 2 P played a key role in optimizing the catalytic active site towards ORR, where charge transfer between P and Co led to activation of the encapsulated carbon shell, as observed previously.…”

Hydrogen Production from Morpholine−Borane by Aluminum Oxide‐Supported Pd Nanoparticles

“…The other additional peaks (orangecolored) observed around 342.7 and 335.8 eV are attributed to 3d regions of PdO. [27][28][29][30] To calculate the activation energy (Ea # ) of the Pd/Al 2 O 3 catalyst in the MB hydrolysis, the catalytic reaction was performed at different temperatures ranging from 298 to 328 K (Figure 5(a)). As can be seen from the figure, the rate of H 2 production gradually increases with increasing temperature, and the rate constant values obtained from the slope of each line from Figure 5(a) are graphed to obtain Arrhenius plot (Figure 5(b).…”