Electrochemical fabrication of multiplicate palladium hierarchical architectures and their electrocatalysis toward oxidation of formic acid

Abstract

Dendritic, cactoid, splintery flowers-like and spinous flowers-like micro/nano-Pd hierarchical architectures were successfully deposited on the conductive substrates without assistance of any templates. Distinct from other general electrodeposition at a constant potential or cyclic potential, we utilized pulse potentials as deposition and dissolution potential, which were controlled by a simple and convenient electrochemical method-differential pulse amperometry. It was found that the morphologies of these novel micro/nanoparticles could be regulated with different pulse potentials. The resulting nanostructures were characterized by scanning electron microscopy and X-ray diffractometry. The results show that series of Pd micro/ nanoparticles were bounded on the different index facets. It means that the growth direction could be effectively controlled by regulating the pulse potentials. Moreover, the as-synthesized Pd micro/nanoparticles also exhibited strikingly difference in catalytic activity toward electrooxidation of formic acid.

Electrocatalytic Performance of Palladium Dendrites Deposited on Titania Nanotubes for Formic Acid Oxidation

“…Although few reports are available in the literature in which noble metals (Pt, Pd) in nanoparticle form on TNT/Ti are used for applications, such as gas sensing 24, solar cells 25 and electrochemical reduction of chloro‐organic pollutants 26, 27, studies directed towards fuel cell applications are limited. There are a few recent reports on the synthesis of noble metal hierarchical structures (such as dendrites, flowers) on substrates such as carbon and indium tin oxide (ITO), which showed improved electro catalytic activity 28–30 for fuel cell applications. The development of noble metal structures, such as dendrites on TNTs, remains unexplored.…”

Electrochemical synthesis of flower-like Pd nanoparticles with high tolerance toward formic acid electrooxidation

“…Nevertheless, in channels where dimensions are of cents of micrometres, the ink painting could not be the best option due to several technical problems like controlling the flow of the thrown material by the spray. Electrochemical deposition technique presents the advantages that nanoparticles with different shape and/or different face exposures can be directly synthesized on the substrate, [20][21][22][23] whereas that for colloidal chemicals is still challenging. Moreover, the catalyst electrodeposition technique is compatible with MEMS and post-CMOS processing, allowing more straightforward integration of MFCs in silicon-based microelectronic applications.…”

Electrochemical synthesis of palladium dendrites on carbon support and their enhanced electrocatalytic activity towards formic acid oxidation

“…Besides, it is observed from the voltammograms that Pd dendritic structures deposited on electrochemically activated carbon have broader peak in the negative scan (at *0.7 V) than that of the Pd deposition on non-activated carbon support. These evidence the better stripping of the absorbed intermediates and regeneration of the Pd surface [47][48][49] on electrochemically activated carbon support and activity towards formic acid oxidation. The improved performance of Pd dendrites on electrochemically activated carbon towards the formic acid oxidation can be attributed to the combination of electrochemical activation of carbon support with dendritic morphology and to better CO tolerance.…”