Microwave assisted indoor- photocatalytic ZnO with various dopants
Papadaki D.
a, b
, Mhlongo G. H
c
, Papadimitriou V.C.
d
, Panagiotaki K.
d
, Nkosi S.S.
e
,
Motaung D. E.
c
, Rosei F.
f
, Kiriakidis G.
a,g
a
Institute of Electronic Structure & Laser (IESL) Foundation for Research and Technology
(FORTH)100, N. Plastira str, Vassilika Vouton GR-70013 Heraklion, Crete, Greece
b
Environmental Engineering Department Technical University of Crete GR-73100 Chania,
Greece
c
DST/CSIR Nanotechnology Innovation Centre, National Centre for Nano-Structured
Materials, Council for Scientific and Industrial Research, P. O. Box 395, Pretoria 0001,
South Africa
d
Chemistry Department University of Crete Vassilika Vouton, GR-71003 Heraklion, Crete,
Greece
e
University of Zululand, Department of Physics and Engineering, Private Bag X1001,Kwa-
Dlangezwa,3886,RSA
f
INRS- Centre Énergie Matériaux Télécommunications, 1650, boulevard Lionel-Boulet
Varennes (Québec) J3X 1S2, Canada
g
Physics Department University of Crete Vassilika Vouton, GR-71110 Heraklion, Crete,
Greece
Corresponding author E-mail address
(D. Papadaki)
In this study, several zinc oxide photocatalytic nanostructures were fabricated via facile
microwave technique for indoor air quality applications. Three dopants have been applied in
our work, Cu, Co and Mn in a 0.25% concentration. The obtained powders were
characterized by X-ray diffraction (XRD), focused ion beam scanning electron microscopy
(FIB-SEM), energy dispersive X-ray spectrometry (EDS), Ultraviolet–visible spectroscopy
(UV−Vis), Photoluminescence (PL) and Brunauer−Emmett−Teller (BET) analysis and X-ray
Photoelectron Spectroscopy (XPS). Structural and morphological results were observed and
are discussed thoroughly in this work. The introduction of dopant increased crystalline size
impressively from 15nm to 18nm for Co, 24nm for Mn and 28nm for Cu doping, however it
reduced porosity for both Mn and Cu doping whereas in Co doping porosity was slightly
increased. Finally the surface area decreased in both Mn and Co, whereas Cu doping
increased its surface area. Further surface analysis is presented through analytical XPS
spectrums and their photocatalytic activities are tested through heterogeneous photocatalytic
degradation of gaseous acetaldehyde (CH
3
CHO) under ultraviolet and visible irradiation, by
employing the Photochemical Static Reactor coupled with Fourier-Transformed Infrared
spectroscopy (PSR/FTIR) technique. It was found that the best indoor photocatalytic material
is ZnO:Co with reaction rate coefficient, k
CH3CHO
= (2.10 ± 0.26)×10-3 min-1 under visible
irradiation making it a possible candidate for indoor photocatalytic applications.
Keywords:
Microwave synthesis, ZnO nanostructures, photocatalysis, Co, Cu, Mn, indoor air quality
PS2 16
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