Post on 25-Jan-2017
International Journal of Minerals, Metallurgy and Materials
V olume 20 , Number 8 , August 2013 , Page 725
DOI: 10.1007/s12613-013-0790-8
Photocatalytic activity of ferric oxide/titanium dioxide nanocompos-
ite films on stainless steel fabricated by anodization and ion implan-
tation
Wei-ting Zhan, Hong-wei Ni, Rong-sheng Chen, Gao Yue, Jun-kai Tai, and Zi-yang Wang
Key Laboratory for Ferrous Metallurgy and Resources Utilization of the Ministry of Education, Wuhan University of Science and
Technology, Wuhan 430081, China
(Received: 6 September 2012; revised: 14 December 2012; accepted: 17 December 2012)
Abstract: A simple surface treatment was used to develop photocatalytic activity for stainless steel. AISI 304 stainless
steel specimens after anodization were implanted by Ti ions at an extracting voltage of 50 kV with an implantation
dose of 3 × 1015 atoms·cm−2 and then annealed in air at 450◦C for 2 h. The morphology was observed by scanning
electron microscopy. The microstructure was characterized by X-ray diffraction and X-ray photoelectron spectroscopy.
The photocatalytic degradation of methylene blue solution was carried out under ultraviolet light. The corrosion resistance
of the stainless steel was evaluated in NaCl solution (3.5 wt%) by electrochemical polarization curves. It is found that the
Ti ions depth profile resembles a Gaussian distribution in the implanted layer. The nanostructured Fe2O3/TiO2 composite
film exhibits a remarkable enhancement in photocatalytic activity referenced to the mechanically polished specimen and
anodized specimen. Meanwhile, the annealed Ti-implanted specimen remains good corrosion resistance.
Keywords: surface treatment; stainless steel; nanocomposite films; photocatalysis; ion implantation; electrochemical
anodization
1. IntroductionDue to its excellent corrosion resistance and mechan-
ical properties, stainless steel has been applied in various
fields such as aerospace, marine, energy, construction, and
household appliances [1-3]. However, stainless steel is sus-
ceptible to being fouled in the presence of organic and inor-
ganic contamination [4-5]. Various methods have been de-
veloped to remove the contamination to prolong the service
life of stainless steel [6-7]. The traditional heavy manual
cleaning work is accompanied by great risk and high cost.
Protective antifouling coatings are effective to alleviate the
problem of corrosion but result in altering the surface me-
chanical properties. In recent years, intense interest has
been paid to the use of semiconductors as photocatalysts to
remove contaminants at radiation conditions [8-9]. Stain-
less steel as an ideal substrate for photocatalysts will ob-
tain potentialities in self-cleaning apparatus and environ-
mental applications. Titanium dioxide, the most promis-
ing candidate among various photocatalysts, has been paid
much attention for its applications such as air/water pu-
rification, sterilization, and solar energy conversion [10-12].
Many studies have been dedicated to coat titanium diox-
ide films on stainless steel by sol-gel deposition, chemical
vapor deposition (CVD), ion implantation [13-15], and so
on. Bestetti et al. [16] coated TiO2 nanopowders on stain-
less steel wire meshes for fluid decontamination by sol-gel
techniques. The photocatalytic activity of the wire meshes
can be remarkably improved by coating TiO2 nanopow-
ders. However, the coatings need repeated loading thick
layers, which present a low adhesion to the substrate and
decreases the hardness of the coated surface. Duminica et
al. [17] studied the photocatalytic activity of a rutile TiO2
film on AISI 304L stainless steel, which was deposited by
CVD at the temperature of 430-600◦C and using titanium
tetraisopropoxide as a TiO2 source. However, CVD meth-
ods for deposition of TiO2 films are usually carried out at
high temperature and the coatings were not homogeneous,
which results in a detachment problem from the substrate.
Corresponding author: Hong-wei Ni E-mail: nihongwei@wust.edu.cn
c© University of Science and Technology Beijing and Springer-Verlag Berlin Heidelberg 2013
726 Int. J. Miner. Metall. Mater., V ol. 20 , No. 8 , Aug. 2013
Compared with other deposition techniques, ion implanta-
tion can be carried out at low temperature, and the proper-
ties of the resulting layer can be exactly controlled by tun-
ing the implantation parameters [18-20]. Moreover, there
is no significant interface between the implanted film and
the substrate.
In the present work, titanium was implanted into AISI
304 stainless steel by a metal vapor vacuum arc (MEVVA)
ion source followed with annealing treatment in air at
450◦C [21-23]. Iron oxide was formed combining with
TiO2 on the annealing Ti-implanted stainless steel surface.
Fe2O3 with the band-gap of 2.2 eV is an interesting n-type
semiconducting material that has been applied to photo-
catalytic applications, such as water splitting, semiconduc-
tor electrodes, and photodegradation of organic pollutants
[24-26], along with its nontoxicity, low cost, and versa-
tile synthesis [27-28]. As reported, composite Fe2O3/TiO2
films exhibited the synergy in photocatalytic ability be-
tween the two photocatalysts [29-31]. The microstructure,
corrosion resistance, and photocatalytic activity of anneal-
ing Ti-implanted stainless steel were explored. The results
showed that the improvement of photocatalytic activity
was due to a nanocomposite Fe2O3/TiO2 film formed on
the stainless steel surface by anodization and ion implan-
tation. This surface treatment of stainless steel will find its
applications in decontaminating the pollution of dissolved
contaminants, nanoparticles, and polluting gases from wa-
ter and air.
2. ExperimentalAISI 304 stainless steel specimens (15 mm × 20 mm ×
0.5 mm) were mechanically polished to a mirror-like sur-
face using abrasive papers (grades 1000, 1200, 1500, and
2000) and diamond pastes of decreasing grade (3.5, 1.0,
and 0.5 µm). Anodization of the mechanically polished
specimens was performed in ethylene glycol (EG; 99.8%
and anhydrous) solution containing 5vol% perchloric acid
(HClO4; 70%) at a constant voltage of 40 V for 10 min
at 5˚C. The anodized specimens were rinsed with ethanol
and double-distilled water in an ultrasonic bath for 20 min.
Ti implantation was carried out on the anodized specimens
under a base pressure of 1 × 10−3 Pa using a titanium cath-
ode with the MEVVA ion source. The implantation dose
was 3 × 1015 atoms·cm−2 with an accelerating voltage of
50 kV at the temperature below 100◦C during implanta-
tion. The implanted specimens were then annealed in air
at 450◦C for 2 h. The mechanically polished specimens,
anodized specimens, and anodized specimens annealed in
air at 450◦C for 2 h were used for comparison of structure
and properties.
Morphologies of specimens were obtained by using an
FEI Nova 400 Nano field-emission scanning electron mi-
croscope (FESEM). The X-ray photoelectron spectroscopy
(XPS) experiments of a Kratos Axis Ultra spectrometer
with an Al anode (Al Kα: 1486.6 eV) were employed to
investigate the chemical composition of the annealing Ti-
implanted stainless steel, calibrated by C 1s at 284.5 eV.
The microstructure of nanocomposite Fe2O3/TiO2 films
was investigated by X-ray diffraction (XRD) using an
XPERT PRO diffractometer with a conventional copper
target at 40 kV and 40 mA with 0.154056 nm wavelength
of Cu Kα.
Electrochemical anodization was carried out on a
direct current power supply (IT6154, ITECH, Nanjing,
China) in a stirred cell at 5◦C with a graphite cathode of
9 cm2. The photocatalytic activity was evaluated by pho-
tocatalytic degradation of methylene blue (MB) at room
temperature in a quartz reactor, in which the specimens
were immersed in 10 mL solution of 2 mg·L−1 MB and
stirred magnetically under the irradiation. The reactor was
placed at a distance of 5 cm from a UV lamp under UV ir-
radiation by the wavelength (λ) of < 400 nm with the den-
sity of radiation power of 20 mW·cm−2. Absorbance values
of MB solution were monitored at 664 nm by a Shimadzu
UV-2550 spectrophotometer. Electrochemical potentiody-
namic polarization curves were measured with a conven-
tional three-electrode system, using the stainless steel spec-
imen as the working electrode, a saturated calomel elec-
trode as the reference electrode, and a graphite foil as the
counter electrode, by a CHI650b potentiostat at a scan
rate of 5 mV·s−1 in a 3.5wt% NaCl solution. The hy-
drophilic properties of the specimens were determined by
the measurement of water contact angle. Recorded images
of droplets with 10 μL deposited on the specimens were
digitized and shape analyses were performed by a software
routine to obtain the contact angle with the precision of
measurement at ±0.5◦.
3. Results and discussionFour typical SEM images of the mechanically pol-
ished specimen, anodized specimen, annealing anodized
specimen, and annealing Ti-implanted specimen are pre-
sented in Fig. 1. The mechanically polished specimen sur-
face is very flat without any stripe or scratch, as shown in
Fig. 1(a). Nanopore arrays are observed on the anodized
specimen surface (Fig. 1(b)). As shown in Figs. 1(c) and
(d), small aggregates of nanosized particles are formed on
the annealed specimen surface covered with homogeneous
and uniform granular coating. From Fig. 1(b), it can be
seen that there are nanopore arrays on the surface of an-
odized specimen. A higher implantation dose will destroy
the morphology of nanopores. Therefore, a low implanta-
tion dose of 3 × 1015 atoms·cm−2 was employed.
To determine the species and chemical states of ele-
ments in thesurface, XPS analysis was carried out. Fig. 2
shows the XPS spectra of the annealing Ti-implanted spec-
imen after a 3-nm-thick surface layer was removed by Ar
ion beam sputtering. Characteristic peaks obtained in the
W.T. Zhan etal., Photocatalytic activity of ferric oxide/titanium dioxide nanocomposite films on ... 727
Fig. 1. SEM images of samples: (a) mechanically polished stainless steel; (b) stainless steel anodized in 5vol%
HClO4 EG solution at the potential of 40 V at 5◦C for 10 min; (c) annealing anodized specimen; (d) annealing
Ti-implanted specimen.
high-resolution spectra mainly corresponded to O 1s, Ti
2p, Fe 2p, Ni 2p, and Cr 2p, respectively. The depth pro-
file of the oxide film is shown in Fig. 2(a). As the depth
ranges from the surface to 24 nm, the XPS quantitative
analysis shows that the content of O element is almost un-
changed of about 41at% compared with nearly zero after
the depth of 60 nm. The contents of Fe, Cr, Ni, and Ti are
about 55at%, 20at%, 0.3at%, and 0.2at% at 24 nm com-
pared with about 75at%, 16at%, 5at%, and 0.3at% at 60
nm. The high-resolution XPS spectra of O 1s, Ti 2p, Fe
2p3/2, Ni 2p3/2, and Cr 2p3/2 at different depths (24 and
60 nm) from the surface were all analyzed in Figs. 2(b)-(f).
The binding energies (BE) of O 1s in Fig. 2(b) are well
fitted with peaks of 529.9 and 531.8 eV, corresponding to
the O2– component and the OH– component (bound wa-
ter) [32-34]. The similar BE peaks of O 1s are observed at
530.4 eV in the depths of 24 and 60 nm, ascribing to the
O2– component [35-37].
On the specimen surface, as shown in Figs. 2(c)-(f),
the intensities of BE peaks for Ti 2p3/2 and Ni 2p3/2 are
so low to the noise level. The peaks centered at 710.4 and
712.8 eV in Fig. 2(d) should be attributed to Fe3+ in Fe2O3
and/or FeOOH on the surface [33-36]. The main peak on
the surface for Cr 2p3/2 is shown in Fig. 2(f) at 577 eV
attributed to Cr3+ in Cr2O3 and/or CrOOH [33-35].
As shown in Fig. 2(c), peaks 1 and 2 at 24 nm centered
at 457.9 and 458.9 eV should be attributed to Ti 2p3/2
of Ti4+ in TiO2, and peak 3 at 463 eV is for Ti 2p1/2.
Whereas the BE peaks at 454.3eV of Ti 2p3/2, 459.3 and
464 eV of Ti 2p1/2, correspond to metallic titanium at 60
nm [20, 31], the Fe 2p3/2 peak at 24 nm is broader than
that at the other depths due to multiplet splitting, which
arises from the interaction of the core hole with unpaired
electrons in the outer shell orbitals [31-34], resulting in a
set of energy shifted final states. The Fe 2p3/2 peak in
Fig. 2(d) at 709.9 eV corresponds to Fe3+at 24 nm with an
additional shake-up peak at 715.2 eV. The peaks locating
at 707.3 and 710.2 eV depict the metallic Fe and Fe3+ at
60 nm, with the dominant area showing the largest contri-
bution from Fe metal. Fig. 2(e) shows the intense peaks
728 Int. J. Miner. Metall. Mater., V ol. 20 , No. 8 , Aug. 2013
Fig. 2. Depth profiles of the annealing Ti-implanted stainless steel prepared by anodization at the potential of
40 V in 5vol% HClO4 EG solution at 5◦C for 10 min: atomic concentration obtained by XPS (a), high-resolution
spectra of depth profiling O 1s (b), Ti 2p (c), Fe 2p3/2 (d), Ni 2p3/2 (e), and Cr 2p3/2 (f).
W.T. Zhan etal., Photocatalytic activity of ferric oxide/titanium dioxide nanocomposite films on ... 729
of 853 eV at 24 nm and 852.9 eV at 60 nm, respectively,
indicating the presence of nickel in elemental state at 24
and 60 nm. Meanwhile, the slight peaks at 854.2 eV in
the depth of 24 nm and 853.7 eV in the depth of 60 nm
represent Ni2+ state in NiO [35-37]. The peak (576.7 eV)
in Fig. 2(f) should be attributed to Cr 2p3/2in Cr2O3 in
the depth of 24 nm. Sputtering to 60 nm [33-35], the BE of
Cr 2p3/2 peaks decrease to 574.1 and 576.3 eV as metallic
chromium and chromium oxide at 60 nm with the domi-
nant Cr metal. The oxide components decrease versus the
sputtering time, and only the metallic component will be
remained below the depth of 60 nm. It is observed that the
distribution of Ti 2p3/2, Ni 2p3/2, and Cr 2p3/2 is similar.
Fig. 3 shows the XRD patterns of the annealing Ti-
implanted specimen with the contrast of the annealing an-
odized specimen and mechanically polished stainless steel.
The XRD spectra (Figs. 3(b) and 3(c)) show the peaks of
phases in oxide films on the austenite stainless steel sur-
face observed in Fig. 3(a) in a similar situation. For the
annealing Ti-implanted specimen, the peak at 2θ = 33◦
was detected as perovskite structure of iron titanium ox-
ide formed by Fe2TiO5 (Fe2O3/TiO2) [38].
The photocatalytic activity of the annealing Ti-
implanted specimen under UV light irradiation is shown in
Fig. 4, referenced by the mechanically polished specimen,
anodized specimen, and annealing anodized specimen. Af-
ter immersion in MB solution in darkness for 2 h, the speci-
mens in MB solution were irradiated with UV light flux for
a duration of 150 min. As shown in Fig. 4(a), the annealing
Ti-implanted specimen exhibits the highest photocatalytic
activity than the referenced specimens. Fig. 4(b) shows
that the degradation of MB follows the pseudo-first-order
kinetics as the linear transforms, ln C0C
= f (t) = kt, where
Fig. 3. XRD patterns of (a) the Ti-implanted stainless
steel annealed in air at 450◦C for 2 h, (b) the annealing
anodized specimen, and (c) the mechanically polished
stainless steel (O—iron titanium oxide peak, S—peaks
of the oxide layer on 316L stainless steel).
k is the reaction rate constant and C0 and C as the ini-
tial and the reaction concentrations of the MB solution.
The values of degradation rate are 0.0040, 0.0048, 0.0096,
and 0.0185 min−1 with the regression coefficients of 0.99,
0.97, 0.98, and 0.99 for the mechanically polished spec-
imen, anodized specimen, annealing anodized specimen,
and annealing Ti-implanted specimen, respectively. Com-
pared with the annealing anodized specimen, the anneal-
ing Ti-implanted specimen shows a significant increase in
the rate of degradation of MB solution. It should be as-
cribed to the nanocomposite Fe2O3/TiO2 film formed on
the stainless steel surface.
Fig. 4. (a) Photocatalytic activity with the values of C/C0 and (b) ln(C0/C) of the stainless steel: (1) mechanically
polishing, (2) anodization at the potential of 40 V in 5vol% HClO4 EG solution at 5◦C for 10 min, (3) the annealing
anodized specimen, and (4) annealing Ti-implanted specimen.
730 Int. J. Miner. Metall. Mater., V ol. 20 , No. 8 , Aug. 2013
Furthermore, annealing reaction leads to generating
Fe2O3/TiO2 composite nanosized particles in a semicon-
ductor surface oxide layer. When the nanocomposite
Fe2O3/TiO2 film is irradiated with UV light, electrons in
the valence bands (VB) of Fe2O3 are easier to be excited to
the conduction bands (CB) than those of TiO2 and leave
holes in the VB [32-33, 39]. As shown in Fig. 5, because
electrons in the CBs of Fe2O3 are driven into the CB of
TiO2, the transport of charge between the bands of Fe2O3
and TiO2 is considered as an effective process inducing an
increase of electron-hole recombination time to promote
the photocatalytic activity of the Fe2O3/TiO2 composi-
tion [23, 27-31].
Fig. 5. Schematic diagram of charge carrier separation
on the Fe2O3/TiO2nanocomposite film.
Fig. 6 shows the behavior of the contact angles of water
on the annealing Ti-implanted specimen and mechanically
polished specimen. The annealing Ti-implanted specimen
(64◦) exhibited a decrease in water contact angles in com-
parison with the mechanically polished specimen (84◦).The annealing Ti implanting can improve the hydrophilic
properties of the specimens.
Fig. 6. Contact angles for the mechanically polished
stainless steel (a) and the annealing Ti-implanted spec-
imen (b).
The anodic polarization curves (Fig. 7) were obtained
from the specimens after 60 min of exposure in 3.5wt%
NaCl solution. The corrosion potential (Ecorr) of the me-
chanically polished specimen, anodized specimen, and an-
nealing Ti-implanted specimen is –0.304, –0.36, and –0.212
V, respectively. The corrosion current density (icorr) of the
mechanically polished specimen, anodized specimen, and
annealing Ti-implanted specimen is 3.711 × 10−7, 3.86 ×10−7, and 2.818 × 10−7 A·cm−2, respectively. The in-
crease in Ecorr and the decrease in icorr indicate that the
corrosion resistance is slightly enhanced after anodization
and ion implantation.
Fig. 7. Electrochemical polarization curves obtained
in a 3.5% NaCl solution of the stainless steel prepared
by mechanically polishing (1), anodization in 5vol%
HClO4 EG solution at the potential of 40 V at 5◦C for
10 min (2), and the annealing Ti-implanted specimen
(3).
4. ConclusionIn this study, a nanocomposite Fe2O3/TiO2 film on
the stainless steel surface was prepared by anodization and
Ti ion implantation. The chemical composition of the an-
nealing Ti-implanted layer depicts that the oxide compo-
nents decrease with increasing depth and almost disappear
at about 60 nm. Annealing treatment leads to forming a
nanocomposite Fe2O3/TiO2 film on the stainless steel sur-
face. The nanocomposite Fe2O3/TiO2 film can prolong the
electron-hole recombination time to promote the photocat-
alytic activity. As a result, the Fe2O3/TiO2 heterojunc-
tion and the nanosized particle surface showed a remark-
able enhancement in UV light activity referenced to the
mechanically polished specimen and anodized specimen.
Electrochemical potentiodynamic polarization curves show
that a slightly enhanced resistance to corrosion is achieved
by anodization and ion implantation. The results suggest
that the annealing Ti-implanted stainless steel has desir-
able photocatalytic activity under UV light radiation and
remains good corrosion resistance.
Acknowledgements
This work was financially supported by the National
Natural Science Foundation of China (Nos. 50771075 and
51171133) and the Program for New Century Excellent
Talents in Universities (No. NCET-07-0650). The Coop-
W.T. Zhan etal., Photocatalytic activity of ferric oxide/titanium dioxide nanocomposite films on ... 731
eration Project in Industry, Education and Research of
Guangdong Province and the Ministry of Education of
China (No. 2011B090400334) is gratefully acknowledged.
References
[1] K. Yang and Y.B. Ren, Nickel-free austenitic stainless
steels for medical applications, Sci. Technol. Adv. Mater.,
11(2010), p. 1.
[2] N. Shaigan, W. Qu, D.G. Ivey, and W.X. Chen, A review
of recent progress in coatings, surface modifications and
alloy developments for solid oxide fuel cell ferritic stainless
steel interconnects, J. Power Sources, 195(2010), p. 1529.
[3] H.B. Li, Z.H. Jiang, Y. Cao, and Z.R. Zhang, Fabrication of
high nitrogen austenitic stainless steels with excellent me-
chanical and pitting corrosion properties, Int. J. Miner.
Metall. Mater., 16(2009), p. 4.
[4] H.W. Ni, H.S. Zhang, R.S. Chen, W.T. Zhan, K.F. Huo,
and Z.Y. Zuo, Antibacterial properties and corrosion resis-
tance of AISI 420 stainless steels implanted by silver and
copper ions, Int. J. Miner.Metall.Mater., 19(2012), p. 4.
[5] L.V.R. de Messano, L. Sathler, L.Y. Reznik, and R.
Coutinho, The effect of biofouling on localized corrosion of
the stainless steels N08904 and UNS S32760, Int. Biodete-
rior. Biodegrad., 63(2009), p. 607.
[6] J. Tavares, A. Shahryari, J. Harvey, S. Coulombe, and S.
Omanovic, Corrosion behavior and fibrinogen adsorptive
interaction of SS316L surfaces covered with ethylene gly-
col plasma polymer-coated Ti nanoparticles, Surf. Coat.
Technol., 203(2009), p. 2278.
[7] Z.Y. Liu, H.W. Bai, and D. Sun, Facile fabrication of hier-
archical porous TiO2 hollow microspheres with high pho-
tocatalytic activity for water purification, Appl. Catal. B,
104(2011), p. 234.
[8] V. Puddu, H. Choi, D.D. Dionysiou, and G.L. Puma,
TiO2 photocatalyst for indoor air remediation: Influence of
crystallinity, crystal phase, and UV radiation intensity on
trichloroethylene degradation, Appl. Catal. B, 94(2010),
p. 211.
[9] G. Palmisano, V. Augugliaro, M. Pagliaro, and L.
Palmisano, Photocatalysis: a promising route for 21st cen-
tury organic chemistry, Chem. Commun., 33(2007), p.
3425.
[10] M. Ni, M.K.H. Leung, D.Y.C. Leung, and K. Sumathy, A
review and recent developments in photocatalytic water-
splitting using TiO2 for hydrogen production, Renew.
Sust. Energ. Rev., 11(2007), p. 401.
[11] A. Paleologou, H. Marakas, N.P. Xekoukoulotakis, A.
Moya, Y. Vergara, N. Kalogerakis, P. Gikas, and D.
Mantzavinos, Disinfection of water and wastewater by
TiO2 photocatalysis, sonolysis and UV-C irradiation,
Catal. Today, 129(2007), p. 136.
[12] C. Giolli, F. Borgioli, A. Credi, A.D. Fabio, A. Fossati,
M.M. Miranda, S. Parmeggiani, G. Rizzi, A. Scrivani, S.
Troglio, A. Tolstoguzov, A. Zoppi, and U. Bardi, Charac-
terization of TiO2 coatings prepared by a modified electric
arc-physical vapour deposition system, Surf. Coat. Tech-
nol., 202(2007), p. 13.
[13] S.J. Yuan, S.O. Pehkonen, Y.P. Ting, K.G. Neoh, and E.T.
Kang, Inorganic-organic hybrid coatings on stainless steel
by layer-by-layer deposition and surface-initiated atom-
transfer-radical polymerization for combating biocorrosion,
ACS Appl. Mater. Interfaces, 1(2009), p. 640.
[14] Y.Y. Chang and D.Y. Wang, Corrosion behavior of electro-
less nickel-coated AISI 304 stainless steel enhanced by ti-
tanium ion implantation, Surf. Coat. Technol., 200(2005),
p. 2187.
[15] P. Evans, M.E. Pemble, and D.W. Sheel, Precursor-
directed control of crystalline type in atmospheric pressure
CVD growth of TiO2 on stainless steel, Chem. Mater.,
18(2006), p. 5750.
[16] M. Bestetti, D. Sacco, M.F. Brunella, S. Franz, R.
Amadelli, and L. Samiolo, Photocatalytic degradation ac-
tivity of titanium dioxide sol-gel coatings on stainless steel
wire meshes, Mater. Chem. Phys., 124(2010), p. 1225.
[17] F.D. Duminica, F. Maury, and R. Hausbrand, Growth of
TiO2 thin films by AP-MOCVD on stainless steel sub-
strates for photocatalytic applications, Surf. Coat. Tech-
nol., 201(2007), p. 9304.
[18] J.T. Chen, G.G. Zhang, B.M. Luo, D.F. Sun, X.B. Yan,
and Q.J. Xue, Surface amorphization and deoxygenation
of graphene oxide paper by Ti ion implantation, Carbon,
49(2011), p. 3141.
[19] H. Savaloni, K. Khojier, and S. Torabi, Influence of N+
ion implantation on the corrosion and nano-structure of Ti
samples, Corros. Sci., 52(2010), p. 1263.
[20] O. Yamamoto, K. Alvarez, Y. Kashiwaya, and M. Fukuda,
Significant effect of a carbon layer coating on interfa-
cial bond strength between bone and Ti implant, Carbon,
49(2011), p. 1588.
[21] Z.H. Li, N.X. Qiu, and G.M. Yang, Effects of synthesis
parameters on the microstructure and phase structure of
porous 316L stainless steel supported TiO2 membranes, J.
Membr. Sci., 326(2009), p. 533.
[22] J. Shang, W. Li, and Y.F. Zhu, Structure and photocat-
alytic characteristics of TiO2 film photocatalyst coated on
stainless steel webnet, J. Mol. Catal. A, 202(2003), p. 187.
[23] M. Asilturk, F. Sayilkan, and E. Arpac, Effect of Fe3+
ion doping to TiO2 on the photocatalytic degradation of
Malachite Green dye under UV and vis-irradiation, J. Pho-
tochem. Photobiol. A, 203(2009), p. 64.
[24] S.K. Mohapatra, S.E. John, S. Banerjee, and M. Misra,
Water photooxidation by smooth and ultrathin α-Fe2O3
nanotube arrays, Chem. Mater., 21(2009), p. 3048.
[25] Z.H. Zhang, M.F. Hossain, and T. Takahashi, Self-
assembled hematite (α-Fe2O3) nanotube arrays for pho-
toelectrocatalytic degradation of azo dye under simulated
solar light irradiation, Appl. Catal. B, 95(2010), p. 423.
732 Int. J. Miner. Metall. Mater., V ol. 20 , No. 8 , Aug. 2013
[26] K.I. Yamada, N. Mukaihata, T. Kawahara, and H. Tada,
Electrochemically assisted visible light photocatalysis in a
heterosupramolecular system consisting of α-Fe2O3 and
surfactant molecular assembly, Langmuir, 23(2007), p.
8593.
[27] X.H. Wang, L. Zhang, Y.H. Ni, J.M. Hong, and X.F. Cao,
Fast preparation, characterization, and property study of
α-Fe2O3 nanoparticles via a simple solution-combusting
method, J. Phys. Chem. C, 113(2009), p. 7003.
[28] Y. Wang, C.S. Liu, F.B. Li, C.P. Liu, and J.B. Liang, Pho-
todegradation of polycyclic aromatic hydrocarbon pyrene
by iron oxide in solid phase, J. Hazard. Mater., 162(2009),
p. 716.
[29] W. Zhou, H.G. Fu, K. Pan, C.G. Tian, Y. Qu, P.P. Lu, and
C.C. Sun, Mesoporous TiO2/α-Fe2O3: bifunctional com-
posites for effective elimination of arsenite contamination
through simultaneous photocatalytic oxidation and adsorp-
tion, J. Phys. Chem. C, 112(2008), p. 19584.
[30] A.I. Kontos, V. Likodimos, T. Stergiopoulos, D.S. Tsouk-
leris, and P. Falaras, Self-organized anodic TiO2 nanotube
arrays functionalized by iron oxide nanoparticles, Chem.
Mater., 21(2009), p. 662.
[31] O. Akhavan and R. Azimira, Photocatalytic property of
Fe2O3 nanograin chains coated by TiO2 nanolayer in visi-
ble light irradiation, Appl. Catal. A, 369(2009), p. 77.
[32] Y.Q. Liang, Z.D. Cui, S.L. Zhu, and X.J. Yang, For-
mation and characterization of iron oxide nanoparti-
cles loaded on self-organized TiO2 nanotubes, Elec-
trochim. Acta, 55(2010), p. 5245.
[33] J. Doff, P.E. Archibong, G. Jones, E.V. Koroleva, P. Skel-
don, and G.E. Thompson, Formation and composition of
nanoporous films on 316L stainless steel by pulsed polar-
ization, Electrochim. Acta, 56(2011), p. 3225.
[34] W.T. Zhan, H.W. Ni, R.S. Chen, X.L. Song, K.F. Huo, and
J.J. Fu, Formation of nanopore arrays on stainless steel sur-
face by anodization for visible-light photocatalytic degra-
dation of organic pollutants, J. Mater. Res., 27(2012), p.
2417.
[35] X.Q. Cheng, Z.C. Feng, C.T. Li, C.F. Dong, and X.G. Li,
Investigation of oxide film formation on 316L stainless steel
in high-temperature aqueous environments, Electrochim.
Acta, 56(2011), p. 5860.
[36] W.J. Kuang, X.Q. Wu, and E.H. Han, The oxidation be-
haviour of 304 stainless steel in oxygenated high tempera-
ture water, Corros. Sci., 52(2010), p. 4081.
[37] R. Parna, E. Nommiste, A. Kikas, P. Jussila, M. Hir-
simaki, M. Valden, and V. Kisand, Electron spectroscopic
study of passive oxide layer formation on Fe-19Cr-18Ni-
1Al-TiC austenitic stainless steel, J. Electron Spectrosc.
Relat. Phenom., 182(2010), p. 108.
[38] D.V. Wellia, Q.C. Xu, M.A. Sk, K.H. Lim, T.M. Lim, and
T.T.Y. Tan, Experimental and theoretical studies of Fe-
doped TiO2 films prepared by peroxo sol-gel method, Appl.
Catal. A, 401(2011), p. 98.
[39] H. Sayılkan, Improved photocatalytic activity of Sn4+-
doped and undoped TiO2 thin film coated stainless
steel under UV- and VIS-irradiation, Appl. Catal. A,
319(2007), p. 230.