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.com
Volume 6
Research & Reviews: Journal of Material Sciences
ISSN: 2321-6212
Advanced Materials 2018
September 04-06, 2018
September 04-06, 2018 | Zürich, Switzerland
21
st
International Conference on
Advanced Materials & Nanotechnology
Ni-based nanowire co-catalysts integrated with a Si photoanode for efficient water oxidation
Meshal S Aljohani, Talal Aljohani, Abduljalil Aljadani, Mohammed Althehaiban
and
Bandar Alotaibi
King Abdulaziz City for Science and Technology, Saudi Arabia
P
hotoelectrochemical water splitting is a sustainable pathway to produce clean hydrogen fuel. Due to the slow kinetics of
the oxidation evolution reaction (OER), the realization of an efficient photoanode remains a great challenge. To lower the
overpotential (
η
) for OER, crystalized and amorphous metal oxides integrated with photoanodes have been recently utilized as
excellent co-catalysts. Considering the high cost of noblemetal oxide catalysts due to their scarcity, such as IrO
2
and RuO
2
, earth-
abundant transition metal oxides, such as Ni-based nanowire electrocatalysts, hold promises for cost-effective and yet efficient
water splitting. Compared to the limitation in charge extraction capability and light blocking of the conventional particle-
based co-catalysts, the flexibility of engineering the morphology and the surface properties of templated Ni-based nanowire
co-catalyts is enormous. That is, highly-ordered templated Ni-based nanowire co-catalyts can be advantageous for their light
trapping, large surface-to-volume ratio, rapid carrier extractions, anti-reflection properties besides lowering the overpotential
(
η
). We demonstrate that engineering the morphology of templated Ni-based nanowire co-catalysts on Si photoanode can lead
to efficient OER. We shall further show that optimizing the surface properties of the nanowire co-catalysts by incorporating
other divalent metal dopants such as Co and Fe can lead to efficient and stable water oxidation with low overpotential. In
this work, Ni-based nanowires arrays are deposited electrochemically and physically on various substrates using ultrathin
anodic aluminum oxide (AAO) template. The length, diameter and thickness of nanowires can be varied depending on the
pores’ dimensions and thickness of the AAO membrane leading to controllable co-catalysts morphology. Shown in figure is
the scanning electron microscopy (SEM) image of pristine NiO nanowires deposited electrochemically on ITO substrate. We
shall further show that by optimizing the surface charge properties through the deposition techniques and incorporating Co
and Fe dopants, the overpotential for OER can be substantially reduced. Full electrochemical properties using three-electrode
configuration in NaOH electrolyte will be presented. Further elemental and structural properties of the nanowire co-catalysts
shall be thoroughly discussed. In brief, the use of such nanowire co-catalysts integrated with Si photoanode for high efficient
and stable photoelectrochemical water splitting shall be demonstrated. This detailed study confirms that the morphology and
surface Ni-based nanowire co-catalysts doped with Co and Fe can lead to lower OER overpotential.
Recent Publications
1. Asif Mahmood, Shahid Mahmood Ramay, Yousef S Al-Zaghayer, Muhammad Imran , Shahid Atiq and Meshal S Al-
Johani (2014)Magnetic and photocatalytic response of Ag-dopedZnFeOnano-composites for photocatalytic degradation
of reactive dyes in aqueous solution. Journal of Alloys and Compounds 614:436–442.
2. Sulaiman I Al-Mayman, Meshal S Al-Johani, Mohamed Mokhtar Mohamed, Yousef S Al-Zeghayer, Shahid M Ramay,
Abdulrahman S Al-Awadi andMoustafa A Soliman (2017) TiO
2
-ZnO photocatalysts synthesized by sol-gel auto-ignition
technique for hydrogen production. International Journal of Hydrogen Energy 42(8):5016-5025.
3. Sulaiman Al-Mayman, Meshal Al-Johani, Kirill Borisevich, Naif Al-Abbadi, Abdullah Al-Musa, Andrey Krauklis and
Pavel Stanovoi (2018) Syngas production at methane decomposition in the plasma of atmospheric pressure high-voltage
discharge. Heat transfer Research 49:12.
Biography
Meshal S Aljohani has been working as an Academic Researcher at King Abdulaziz City for Science and Technology since 2016. He has completed his Master’s
degree in Chemical Engineering at King Saud University in 2015. His Master’s thesis is entitled as “Photocatalytic production of hydrogen from ethanol-water
solution using TiO
2
-ZnO.” He is currently working on “Fabrication of solar water-splitting device project” collaboration with the University of Cambridge, which is
aiming to produce hydrogen from renewable energy sources. His current work focuses on oxides and perovskite-based materials to achieve highly efficient and
stable solar fuel with low cost and high scalability.
maljuhni@kacst.edu.saMeshal S Aljohani et al., Res. Rev. J Mat. Sci. 2018, Volume 6
DOI: 10.4172/2321-6212-C3-021