Palladium (Pd) dendrites were synthesized on electrochemically activated carbon (Vulcan XC-72R) support by a simple template free potentiostatic (constant voltage) deposition. Scanning electron micrographs displayed a dendritic morphology when deposited at potentials &lt;0.5 V (vs. RHE), whereas spherical aggregates were obtained at potentials &gt;0.5 V. Transmission electron micrographs and X-ray diffraction pattern confirmed the difference in morphological features and growth of Pd dendrites. Pd deposited at 0.4 V showed higher electrochemical surface area of 128.5 m2 g−1 in comparison to 25.1 m2 g−1 obtained for Pd deposited at 0.5 V and also displayed enhanced activity towards formic acid oxidation. © 2016 Hydrogen Energy Publications LLC

Raghuram Chetty

Department Of Chemical Engineering

Kranthi Kumar Maniam

Volga Muthukumar

Activated carbon

Bamboo

Biomass

Capacitance

Capacitors

Carbonates

Charge transfer

Electrolytic capacitors

FUSED SALTS

Heat storage

Porous materials

BAMBOO SHELLS

MOLTEN CARBONATE

Molten salt

Super capacitor

WASTE BIOMASS

Carbonization

IIT Madras is a public technical and research university located in Chennai, Tamil Nadu. Founded in 1959, it is recognised as an Institute of National Importance.

IIT Madras has been ranked as the top engineering institute in India for four years in a row by the National Institutional Ranking Framework of the MHRD

It currently offers undergraduate, postgraduate and research degrees across 16 disciplines in Engineering, Sciences, Humanities and Management. About 596 faculty belonging to science and engineering departments and centres of the Institute are engaged in teaching, research and industrial consultancy.

IIT Madras

International Journal of Hydrogen Energy

Palladium (Pd) dendrites on carbon black support were synthesized by a simple template/surfactant-free electrochemical deposition. In comparison to Pd spherical deposit obtained on non-activated carbon, Pd deposited on an electrochemically activated carbon displayed a dendritic morphology with increased electrochemical surface area and showed enhanced catalytic activity for formic acid oxidation. The effect of electrochemical activation and deposition cycles were studied in relation to the growth and morphological features of Pd deposit. Scanning electron micrographs and X-ray diffraction studies showed a transition in Pd morphology from spheres to dendrites when the carbon support was subjected to varying cycles of electrochemical activation, prior to Pd deposition. Raman and X-ray photoelectron spectra results showed that the defects induced during electrochemical activation on carbon played a major role in tailoring the Pd morphology. © 2015, Springer Science+Business Media Dordrecht.

Journal of Applied Electrochemistry

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

Palladium (Pd) was electrochemical deposition on activated carbon from chloride precursor in acid media. The effect of precursor concentration was studied in relation to the dispersion of Pd at a particular deposition potential, and the influence of support material such as conventional Vulcan XC-72R (VXC) and activated carbon prepared from Wood Apple Shell (WAS) on the dispersion of Pd is investigated. Scanning electron microscope images showed, changing the support from VXC to WAS carbon improved the dispersion of Pd, and CO stripping and hydrogen adsorption desorption experiments displayed an increase in electrochemical surface area for Pd on WAS carbon support. Comparison of electrochemical data for oxygen reduction reaction and formic acid oxidation suggests that Pd deposited on wood apple shell (WAS) carbon showed higher activities relative to Pd deposition on Vulcan. Cyclic and linear sweep voltammetry results showed a positive shift in onset potential up to 80 mV towards oxidation and reduction reactions on changing the support to WAS carbon. The effectiveness of improving the utilization of Pd by changing the support from VXC to WAS activated carbon is discussed in detail. © 2014 The Authors.

Fulltext

Energy Procedia

Approaches towards improving the dispersion of electrodeposited palladium on carbon supports

Palladium was electrodeposited on an electrochemically activated carbon black substrate using potentiostatic technique, with and without the addition of polyethylene glycol (PEG-6000) as an additive. Scanning electron micrographs showed change in morphology of Pd from spherical to flower, with increasing additive concentration. As an electrocatalyst for oxygen reduction reaction (ORR), formic acid oxidation and CO stripping, Pd nanoflowers displayed three- to fourfold increase in electrocatalytic activity in comparison to the spherical Pd deposits in terms of electrochemical surface area (ESA) and mass specific current density. X-ray diffraction (XRD) patterns showed, the introduction of additive with varying concentration effect the direction of Pd growth thereby changing the morphology from spherical to flower. The result demonstrates an increase in efficiency of Pd utilization achieved with the addition of PEG during electrodeposition, which could also be applicable to other precious metal electrocatalysts. A scheme for the change in Pd morphology during electrodeposition with additive is also proposed. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Fuel Cells

Electrodeposited palladium nanoflowers for electrocatalytic applications

Chemical Reviews

Palladium-Based Nanomaterials: Synthesis and Electrochemical Applications

Journal of Power Sources

Novel palladium flower-like nanostructured networks for electrocatalytic oxidation of formic acid

Electrodeposition of dendritic palladium nanostructures on carbon support for direct formic acid fuel cells

Journal	Data powered by TypesetInternational Journal of Hydrogen Energy
Publisher	Data powered by TypesetElsevier Ltd
ISSN	03603199
Open Access	No