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Journal of Industrial and Environmental Chemistry
|
Volume 2
GREEN CHEMISTRY &
TECHNOLOGY
7
th
International Conference on
J u n e 1 8 - 2 0 , 2 0 1 8 | D u b l i n , I r e l a n d
Thillai Sivakumar Natarajan et al., J Ind Environ Chem 2018, Volume 2 | DOI: 10.4066/2591-7331-C1-002
SYNTHESIS OF VISIBLE LIGHT
RESPONSIVE CU(OH)
2
LOADED ZNIN
2
S
4
PHOTOCATALYST FOR PRODUCTION
OF RENEWABLE HYDROGEN BY NON-
SACRIFICIAL WATER SPLITTING
Thillai Sivakumar Natarajan
and
K Ravindranathan Thampi
University College Dublin (UCD), Ireland
T
he conversion and storage of solar energy in the form of hydrogen (H
2
)
is a clean, affordable and sustainable fuel to meet the future energy
requirement. Semiconductor based photocatalytic system for splitting of
water under light irradiation is widely recognised as a sustainable method
to produce H
2
. Different stable oxide semiconductors have been used
hitherto; however, their H
2
production efficiency is poor, due to their low
visible light response, the position of conduction band (CB) potentials,
rapid recombination of photogenerated electrons and holes. As a result,
various visible light responsive materials have been developed, among
those ternary chalcogenides like zinc indium sulphide (ZnIn
2
S
4
) has
displayed excellent visible light photocatalytic activity for the required
reactions. It is endowed with a CB potential (~0.8-1.1 eV) higher than
the H
2
(H
+
/H
2
, 0 V) evolution potential and a lower band gap (~2.2 eV).
However, their low charge separation efficiency tends to decrease the net
H
2
production efficiency. To overcome this, different co-catalysts were
loaded, among those, transition metal hydroxide (M(OH)
2
where, M-Co,
Ni, Cu) has been reported as an effective co-catalyst for H
2
evolution.
However, the water splitting reactions are studied mainly in the presence
of sacrificial agents such as alcohols, Na
2
S, Na
2
SO
3
, triethanolamine.
The use of sacrificial agents is not useful for practical applications as it
is economically not viable. Therefore, herein we describe the synthesis
of visible light responsive Cu(OH)
2
loaded ZnIn
2
S
4
photocatalyst for
non-sacrificial water splitting to produce H
2
, for the first time. Cu(OH)
2
-
ZnIn
2
S
4
was synthesized via a facile hydrothermal method followed by
precipitation and the samples were characterized using various physico-
chemical techniques. The H
2
production efficiency of photocatalyst
was investigated by non-sacrificial water splitting under visible light
irradiation. The results revealed that Cu(OH)
2
/ZnIn
2
S
4
showed enhanced
H
2
production capacity than the pristine ZnIn
2
S
4
. This is attributed to
the efficient separation of the charge carriers and the boosted catalytic
activity of surface sites. This work would further lift the interest in
developing visible light responsive photocatalysts for non-sacrificial solar
water splitting.
Thillai Sivakumar Natarajan has completed
his PhD from CSIR-CSMCRI, Gujarat, India, in
2014 and then moved to South Korea and Tai-
wan for his Post-doctoral research and worked
there until August 2016. In November 2016, he
moved to Ireland and has been working as a
Post-doctoral Researcher at School of Chemical
and Bioprocess Engineering, University College
Dublin, Ireland, under an Irish Research Council
through Government of Ireland Post-doctoral
Fellowship-2016 scheme. His research work
mainly focuses on development of photocata-
lytic nanomaterials and surfaces and their use
with different light sources (UV, solar and LED)
in slurry and immobilized photocatalytic reac-
tors for environmental remediation and energy
applications. He has 20 research papers in inter-
nationally reputed journals and 4 book chapters.
His publications have been cited over 800 times
with the H-index of 12.
thillai.natarajan@ucd.ieBIOGRAPHY