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Ultrasonics - Sonochemistry
journal homepage: www.elsevier.com/locate/ultson
Preface
The Use of Power Ultrasound and Sonochemistry for the Production of Energy Materials
The fabrication and use of nanomaterials for electrochemical energy
storage devices (ESD) such as fuel cells, electrolysers, batteries and
supercapacitors have been of great interest in the academic and in-
dustrial communities due to their unique properties. The important
mechanism controlling the nanosized material is nucleation and
growth, depending strongly upon the synthetic routes employed. Many
methods exist for the synthesis of nanoparticles, including alcohol re-
duction, citrate reduction, polyol reduction, borohydride reduction,
photolytic reduction, radiolytic reduction, laser ablation, and metal
evaporation condensation, to name but a few. However, the synthesis of
these materials at large scale can be challenging due to the high cost,
intense labour and use of hazardous solvents.
Since the publication of ‘The use of ultrasound for the fabrication of
fuel cell materials’ in the International Journal of Hydrogen Energy (IJHE)
in 2010 [1], there has been an upsurge of international interest in the
use of power ultrasound, sonochemistry, and sonoelectrochemistry for
the production of electrochemical ESD nanomaterials. For example, it
has been shown that it is possible to employ power ultrasound for the
preparation of Proton Exchange Membrane Fuel Cell (PEMFC) and
Proton Exchange Membrane Water Electrolyser (PEMWE) catalysts [2].
The review detailed the ultrasonic, sonochemical, and sonoelec-
trochemical generation of noble metal electrocatalysts with nanosizes
of < 10 nm with and without the addition of surfactants and alcohols,
carbon supported electrocatalysts, fuel cell electrodes, and membranes.
The paper showed that (i) the production of these nanomaterials is
mainly attributed to the presence of radical species induced by water
sonolysis, (ii) the nanomaterial size depends strongly upon the ultra-
sonic frequency and irradiation time, surfactant, alcohol, and atmo-
spheric gas types, and (iii) the as-prepared catalyst on carbon nano-
materials leads to excellent electrocatalytic activity due to carbon
support surface functionalization and effective dispersion caused by
sonication [1,2].
Sonochemistry is therefore a powerful hybrid technique that com-
bines power ultrasound and chemistry in a specially designed chemical
setup, which can be effectively used to produce energy nanomaterials
with controlled sizes and shapes. Moreover, the scalability of so-
nochemistry for fabricating nanomaterials at industrial scale is possible
due to its “one-pot” synthetic approach [3,4] (Fig. 1).
This special issue entitled “The Use of Power Ultrasound and
Sonochemistry for the Production of Energy Materials” contains 11
Fig. 1. Representative TEM images of (a) Pt nanoparticles, and (b) Pt nanoparticles formed directly sonoelectrochemically onto the carbon particles. The particle size
distribution of the carbon supported Pt nanoparticles is also shown in (c). Modified from [4].
https://doi.org/10.1016/j.ultsonch.2019.104851
Ultrasonics - Sonochemistry 64 (2020) 104851
Available online 02 November 2019
1350-4177/ © 2019 Elsevier B.V. All rights reserved.
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selected papers highlighting the use of ultrasound and sonochemistry
for the fabrication of energy materials, ranging from OER (Oxygen
Evolution Reaction), ORR (Oxygen Reduction Reaction) catalysts to
nanomaterials for SOFC (Solid Oxide Fuel Cell), supercapacitors, su-
percapattery and photocatalysis. I would like to take the opportunity to
thank all authors for their contributions as well as the assistance from
colleagues who reviewed these manuscripts. I would also like to thank
Prof. Ashokkumar and all Executive Editors of Ultrasonics Sonochemistry
for their continuous support.
References
[1] B.G. Pollet, The use of ultrasound for the fabrication of fuel cell materials, Int. J.
Hydrog. Energy 22 (2010) 1039–1059.
[2] B.G. Pollet, The use of power ultrasound for the production of PEMFC and PEMWE
catalysts and low-Pt loading and high-performing electrodes, Catalysts 9 (2019)
246–264.
[3] Md Hujjatul Islam, Michael T.Y. Paul, Odne S. Burheim, Bruno G. Pollet, Recent
developments in the sonoelectrochemical synthesis of nanomaterials, Ultrason.
Sonochem. 59 (2019) 104711–104719.
[4] D.S. Karousos, K.I. Desdenakis, P.M. Sakkas, G. Sourkouni, B.G. Pollet, C. Argirusis,
Sonoelectrochemical one-pot synthesis of Pt–carbon black nanocomposite PEMFC
electrocatalyst, Ultrason. Sonochem. 35 (2017) 591–597.
Guest Editor
Bruno G. Pollet
Preface Ultrasonics - Sonochemistry 64 (2020) 104851
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