C/TiO2 nanohybrids co-doped by N and their enhanced photocatalytic ability

Article abstract of DOI:10.1016/j.jssc.2012.04.033

N-doping carbon-TiO₂ nanohybrids (NCTs, nitrogen not only in situ doped carbon film but also doped TiO₂ nanocrystals, and 5-10 nm TiO₂ nanocrystals evenly dispersed on N-doping carbon film) have been successfully prepared by a mild, one-step approach. N-O-Ti chemical bonds between N-Carbon film and N-TiO₂ nanoparticles were formed, and here, N-Carbon can not only sensitize and modify TiO₂ nanocrystals surface, but also N can dope in the TiO₂ nanocrystals. The as-prepared NCTs were investigated by X-ray photoelectron spectroscopy, TEM, FT-IR, electrochemistry method. It was demonstrated that the as-obtained NCTs have a large BET specific surface area of 279.43 m²/g. The NCTs show excellent photocatalytic abilities towards organic (Rhodamine B) and inorganic pollutant (K₂Cr₂O₇) degradation under visible light irradiation. This work provided a new approach for the high performance catalyst design towards new energy sources and environmental issues.

Full text of DOI:10.1016/j.jssc.2012.04.033

Journal of Solid State Chemistry 192 (2012) 305–311
Contents lists available at SciVerse ScienceDirect
Journal of Solid State Chemistry
journal homepage: www.elsevier.com/locate/jssc
C/TiO nanohybrids co-doped by N and their enhanced photocatalytic ability
2
n
n
Hai Ming, Hui Huang, Keming Pan, Haitao Li, Yang Liu , Zhenhui Kang
Institute of Functional Nano and Soft Materials (FUNSOM) & Jiangsu Key Laboratory for Carbon Based Functional Materials and Devices, Soochow University,
Suzhou, Jiangsu 215123, People’s Republic of China
a r t i c l e i n f o
a b s t r a c t
Article history:
N-doping carbon–TiO2 nanohybrids (NCTs, nitrogen not only in situ doped carbon film but also doped
TiO2 nanocrystals, and 5–10 nm TiO2 nanocrystals evenly dispersed on N-doping carbon film) have
been successfully prepared by a mild, one-step approach. N–O–Ti chemical bonds between N–Carbon
Received 16 February 2012
Received in revised form
1
6 April 2012
film and N–TiO
2
nanoparticles were formed, and here, N–Carbon can not only sensitize and modify TiO
nanocrystals. The as-prepared NCTs were
2
Accepted 17 April 2012
Available online 25 April 2012
nanocrystals surface, but also N can dope in the TiO
2
investigated by X-ray photoelectron spectroscopy, TEM, FT-IR, electrochemistry method. It was
Keywords:
2
demonstrated that the as-obtained NCTs have a large BET specific surface area of 279.43 m /g.
TiO
2
The NCTs show excellent photocatalytic abilities towards organic (Rhodamine B) and inorganic
Nanohybrids
N doping
pollutant (K
for the high performance catalyst design towards new energy sources and environmental issues.
2012 Elsevier Inc. All rights reserved.
2 2 7
Cr O ) degradation under visible light irradiation. This work provided a new approach
Photocatalyst
&
1
. Introduction
TiO based photocatalysts have been one of the most active
an idea emerged, that is whether we can obtain the C/TiO
photocatalyst with N doping in two components (C and TiO
simultaneously. In some sense, this complex system may provide
an opporunity to realize the high visible light sensitivity structural
and catalytic stability at the same time.
2
hybrid
2
)
2
topics in heterogeneous catalysis due to their great catalytic
abilities for removing environmental pollutants and water spilling
[
1–4]. TiO
2
catalyst is usually in pursuit of forming nanoparticles
Herein, at the core of these objectives, a new kind of photo-
with high specific surface area, wide-range wavelength of light
sensitivity, and high activity. Notably, in order to tune or improve
the catalytic abilities, an efficient strategy is to dope or modify
2
catalyst, C/TiO nanohybrids co-doped by N (NCTs), has been
successfully prepared via a cosurface chemistry approach. The
mechanistic and electronic model constructed in this study
provides insight into factors controlling the photocatalysis effi-
ciency and clearly elucidates the crucial roles of N doped C
nanostructures as active species in the photocatalytic degradation
of organic and inorganic toxic pollution.
2
TiO nanostructures with transition metals/non-metal elements
or other semiconductors, dyes, metal and carbon nanoparticles
[
5–8]. Among these methods, TiO
2
functionallization by carbon
(C) and nitrogen (N) has received much attaction due to the
simple and easy control process, mild reaction condition and
resulted efficient visble light absorption [9–13]. However, TiO
nanostructures reported in most of these work still suffer from
the unstable nature during the catalytic reactions [12,13]. Con-
quering this drawback is also the significant and urgent challenge
in nanochemistry and photocatalysis.
As known, N is considered to be an excellent element for the
stable chemical doping of C nanostructures (C nanotubes and
graphene) to improve their photoelectron related properties and
broaden their potential applications in biosensors [14], fuel cells
2
2
. Material and methods
2.1. Preparation of NCTs
2.1.1. All chemicals were used as received without further
purification.
2
.1.1.1. Preparation of TiO
purchased from Alfa Aesar Co. Ltd., named as TBT), placed
parallel with a dosage of 4 mL, were dissolved into 100 mL ultra-
pure ethanol, named solution A. Later, 200 mL H O (adjusted pH
with HCl) was transferred to a three-neck flask (capacity, 500 mL)
2
nanoparticles. Tetra-n-butyl Titanate
(
[
[
15], photoelectronic devices [16], and photocatalysis fields
17–19]. In light of this point and the benefits of N doping on
2 2
TiO (N–TiO , significantly enhanced visible light sensitivity) [9–11],
2
1
and heated at 343 K in the oil bath. Solution A (1 mL/min) was
intruducted into three-neck flask under vigorous machine stirring
to promote the hydrolysis of TBT, and then a white colloid solution
n
Corresponding authors. Fax: þ86 512 65882846.
E-mail addresses: yangl@suda.edu.cn (Y. Liu), zhkang@suda.edu.cn (Z. Kang).
0022-4596/$ - see front matter & 2012 Elsevier Inc. All rights reserved.
http://dx.doi.org/10.1016/j.jssc.2012.04.033

3
06
H. Ming et al. / Journal of Solid State Chemistry 192 (2012) 305–311
appeared in the reactor. The colloid solution was kept at 343 K for
8 h. After that, the product was washed with ethanol and water for
several times.
follows: prior to the surface coating, the GCE was polished
carefully with 0.5 m and then with 0.05 m alumina powder,
4
m
m
and followed by sonication in 1:1 nitric acid/water (v/v), acetone
and in doubly distilled water successively. The surface of GCE was
allowed to dry under nitrogen atmosphere. The samples (P25 and
NCTs) were ultrasonically dispersed in water to form a homo-
geneous dispersion (1 mg/mL). The surface of GCE was coated
2
2.1.1.2. Formation of the NCTs. The as-prepared TiO nanoparticles
were dispersed in ethylenediamine (EDA, 80 mL), transferred into
three-neck flask and kept at a constant temperature of 393 K for
2
4 h, successively. After that, the EDA suspension was cooled to
room temperature and kept at 353 K for 72 h. When the redundant
EDA volatilized overall, deep yellow TiO powders were obtained
TiO nanoparticles coated with polymer EDA). Finally, black NCTs
with 5
m
L of the sample and then dried in air. The surface of
modified GCE was further coated with 5
solution (0.2 wt%) and then dried in air before the electrochemical
experiments.
mL of Nafion ethanol
2
(
2
were achieved through calcinating the sample at 873 K for 5 h
under Argon flow to promote crystallization.
2
2
.3. Photocatalytic abilities test
2.2. Electrochemical test
.3.1. Photodegradation of rhodamine B (RhB)
Electrochemical test experiments were performed with an
A tungsten-halogen with light power of 50 W and the wave-
IM6e potentiostat (Zahner Elektrik Company, Germany) in a
conventional three-electrode cell. The electrode assembly consists
of a platinum wire as the counter electrode, an Ag/AgCl/KCl (sat)
electrode as the reference electrode, and a glassy carbon electrode
length of emission light ranged from 400 to 2500 nm, which was
positioned inside a cylindrical vessel, surrounded by a circulating
water jacket for cooling. 0.15 g NCTs photocatalyst (or 0.09 g P 25,
2
the addition amount of TiO is equivalent) was suspended
(
GCE, d¼3 mm) as the working electrode. The measurement
in 100 mL aqueous solution of 40 ppm RhB. The solution was
stirred for 12 h to ensure the establishment of an adsorption–
desorption equilibrium. The system was then irradiated with
tungsten-halogen light, 3 mL aliquots were removed at certain
4
ꢀ/3ꢀ
buffer contains 0.25 mM [Fe (CN)
6
]
and 0.05 M KCl as redox
indicator. Cyclic voltammetry (CV) was recorded in the range of
1–1 V and with a scan rate at 50 mV/s. The GCE was prepared as
ꢀ
Fig. 1. (a) XRD pattern and (b) XPS full spectrum of NCTs. (c) TEM image. Inset: digital image of NCTs solution. (d) HRTEM image. Inset: HRTEM image of single N–TiO
on N doped C film (N–Carbon).
2

H. Ming et al. / Journal of Solid State Chemistry 192 (2012) 305–311
307
time intervals and analyzed on a UV–vis spectrophotometer to
record concentration.
drying a dispersion of micro-crystals on a piece of Cu wafer. Room
temperature UV–vis absorption was recorded on a Lambda 750
(
2
PerkingElmer) spectrophotometer in the wavelength range of
00–800 nm. Fourier transform infrared (FT-IR) was recorded on
a Ventrix (Brukle) spectrophotometer in the wavelength range of
00–4000 nm. XANES measurements at N K-edge were performed
6
þ
2.3.2. Photoreduction of inorganic toxic pollution (Cr
)
A tungsten-halogen with light power of 50 W and the wave-
4
length of emission light ranged from 400 to 2500 nm, which was
positioned inside a cylindrical vessel and surrounded by a
circulating water jacket for cooling. 0.15 g photocatalyst (NCTs)
and 1.0404 g CHOONa were suspended in 100 mL aqueous solu-
in transmission mode at U7C XAFS station in NSRL (National
Synchrotron Radiation Laboratory, PR China). The storage ring of
PF-AR was operated at 6.5 GeV with the maximum current of
1
1
ꢀ1
450 mA. An approximate X-ray photon flux of 10 photons s
2 2 7
tion of 50 ppm K Cr O . The solution was stirred for 12 h to
was monochromatized using a Si (3 1 1) monochromator. The
storage ring of NSRL was run at 0.8 GeV with the maximum
current of 200 mA.
ensure the establishment of an adsorption–desorption equili-
brium. The system was then irradiated with tungsten-halogen
light, 3 mL aliquots were removed at certain time intervals and
analyzed on a UV–vis spectrophotometer to record concentration.
3. Results and discussion
2.4. Measurement and characterization
3.1. Nanostructure of NCTs
The obtained products were characterized by X-ray powder
diffraction (XRD) using a X‘Pert-ProMPD (Holand) D/max-
gA X-ray
As shown in the X-Ray Diffraction (XRD) patterns (Fig. 1(a)),
diffractometer with Cu K radiation (
a
l
¼0.154178 nm). The XRD
after calcination, the crystalline structure of NCTs (red curve)
sample is anatase phase (JCPDS: 84-1286). Notably, the charac-
teristic peak for C at 26.21 (0 0 2) is suppressed by the peak of
measurement conditions: the scanning current is 40 mA, the
scanning voltage is 40 kV, the scanning step is 0.0261 and the
scanning rate is 0.26261/s. Scanning electron microscopy (SEM)
images and EDX were taken on a FEI-quanta 200F scanning
electron microscope with acceleration voltage of 20 kV. Transmis-
sion electron micrographs (TEMs) were taken on a FEI-Tecnai F20
2
25.21 belonging to (1 0 1) plane of TiO . While before calcination,
NCTs are mainly composed of amorphism crystal phase (black
curve). X-ray Photoelectron Spectroscopy (XPS) spectrum of the
NCTs (Fig. 1(b)) exhibits C1s, O1s, N1s, Ti 2p, and Cu2p3/2
(substrate) peaks after calcination. No other peaks of impurities
are detected, indicating the high purity of NCTs. The atom ration
of Ti, O, C and N in NCTs (inset in Fig. 1(b)) are 14.42%, 37.09%,
30.21%, and 18.28%, respectively. TEM image (Fig. 1(c)) presents
(200 kV) transmission electron microscope (FEI). X-ray Photoelec-
tron Spectroscopy (XPS) was obtained by using a KRATOS Axis
ultra-DLD X-ray photoelectron spectrometer with a monochroma-
tised Mg K X-ray (hn¼1283.3 eV). XPS samples were prepared by
a
Fig. 2. (a) Ti2p, (b) O1s, (c) C1s, (d) N1s spectra of NCTs.

3
08
H. Ming et al. / Journal of Solid State Chemistry 192 (2012) 305–311
the formation of NCTs, in which N–TiO
nm and nicely distributed on the N–Carbon. NCTs solution with
better clarity is shown in the inset of Fig. 1(c). The HRTEM image
Fig. 1(d)) clearly reveals the homogeneous distribution of TiO
2
with average diameter of
nitrogen K-edge XANES spectrum (Fig. 3) of NCTs, in which four
n
8
main
peaks
of
1s-p
((a),
C–N,
398.1 eV),
n
n
p
resonance in pyridine ((b), C¼N–C, 400.7 eV),
p
resonance in
n
(
2
pyrrole ((c), C–NH–C, 402.1 eV) and 1s-s ((d), N–O, 406.2 eV)
nanoparticles (marked with green circle) on the N–Carbon (wavy
or curled morphology). The corresponding HRTEM image
were observed. As known, there are only C–N and N–H chemical
bonds in ethylenediamine (EDA), while C and O atoms belong to C
(
Fig. 1(d), inset) reveals the junction formation between N–
Carbon and N–TiO . N–TiO generally exhibit a round shape with
good crystallinity, and the lattice fringes (d¼0.35 nm) corre-
sponding to the TiO (1 0 1) plane, and the curled morphology
film and TiO
N–O indicates that N has been successfully doped in C film and
TiO nanoparticles, respectively, forming a N doping interface
between C and TiO [18]. FT-IR spectrum (Fig. 4(a)) of NCTs shows
five peaks located at 3417 cm
2
, respectively. Therefore, the observation of C–N and
2
2
2
2
2
ꢀ
1
ꢀ1
marked by the arrow indicates the N–Carbon film.
(OH), 3416 cm
(N–H),
ꢀ
1
ꢀ1
ꢀ1
XPS spectrum of Ti 2p (Fig. 2(a)) reveals two prominent peaks at
1620 cm
(N–O, C¼C), 1401 cm
(C–C, C–H) and 596 cm
4
58 eV (Ti 2p3/2) and 464 eV (Ti 2p1/2). According to the fitting
peaks area, there should be only Ti–O (458.7, 459.2, 464.5,
65.2 eV) chemical bond (belonging to TiO ). In the XPS spectrum
(Ti–O). The existence of hydroxy groups in the sample is attributed
to re-adsorption of water from the atmosphere. Raman spectrum
4
2
(Fig. 4(b),
(D, sp3) and 1546 cm
indicates the high amorphous degree of N–Carbon.
lex¼633 nm) of NCTs shows two C peaks located at 1324
ꢀ1
of O1s (Fig. 2(b)), two dominating peaks of O–Ti (530.4 eV) and N–
O (529.8 eV) were observed. Four dominating peaks at 284.1,
(G, sp2), and the ratio of I
/I
D G
¼1.19
ꢀ
1
ꢀ1
2
84.6, 285.1, and 286.9 eV belonging to sp2 or sp3 carbon were
detected in the XPS spectrum of C1s (Fig. 2(c)), and the peaks at
85.6 and 286.1 eV peak were attributed to C–N. XPS spectrum of
The rest three peaks located at 391 cm
(B1g), 506 cm
, and the high E1g peak suggests
the NCTs are of anatase phase. From the Raman spectrum, we can
also see that N–TiO vibration framework did not change after
combination and doping. All of the above results indicated that
there were only N–O–Ti bond between N–Carbon and N–TiO
nanoparticles, and here, N–Carbon can not only sensitize and
modify TiO nanocrystals surface, but also N can dope in the TiO
nanoparticles [9–11].
(A1g)
ꢀ
1
and 627 cm (E1g) belong to TiO
2
2
N1s (Fig. 2(d)) illuminated that N atoms were either combined
with C atoms (398.7 eV) and O atoms (400.7 eV). In all of above
XPS spectra, there is no C–Ti (282, 281.6, 454.9 eV), C–O (287.3 eV),
Ti–N (396, 396.6 eV) bond observed. We further measured the
2
2
2
2
For the formation of NCTs nanohybrids in the present reaction
system, we try to explain the formation process based on the
experimental route as follows (see Fig. 5). At first, during the
reflux process (393 K, 24 h), due to the alkalescence of EDA,
the surface of TiO
EDA can be doped in the TiO
be continuously polymerized and formed a polymer EDA layer on
the surface of the TiO nanoparticles. And then, during the
2
nanoparticles can react with EDA, and N in
2
nanoparticles. Meanwhile, EDA can
2
volatilization process (353 K, 72 h), redundant EDA will volatilize,
but due to high saturated vapor pressure and viscosity of polymer
EDA, polymer EDA will be coated on the surface of TiO
particles (deep yellow TiO powders). Based on plenty of hydroxyl
functional groups and oxygen-containing groups on the surface of
TiO nanoparticles and amidocyanogen functional groups in the
polymer EDA, TiO nanoparticles will in situ assemble and
2
nano-
2
2
2
dehydrate on the polymer EDA. Finally, this interaction can be
further enhanced by the carbonization of polymer EDA during
calcination (873 K, 5 h). In this process, the defects in N–Carbon
are occupied by amidocyanogen groups and there is no unsatu-
Fig. 3. Nitrogen K-edge XANES spectrum of NCTs.
2
rated C suspension bond. Moreover, TiO nanocrystals surface
Fig. 4. (a) FT-IR and (b) Raman spectra of NCTs.

H. Ming et al. / Journal of Solid State Chemistry 192 (2012) 305–311
309
3
2
only have oxygen-containing groups and Ti–C bond is too hard to
construct. Thus, the formation of NCTs is reasonable.
0.5750 cm /g and 96.66 m /g, respectively. Typical UV–vis diffuse
reflectance absorption spectra (Fig. 6(b)) indicate that the
band gap absorption onset of P25 is located at about 380 nm
(
black curve), while NCTs show an efficient absorption in visible
band, implying the good photocatalytic ability under visible light
red curve). The blue curve for the simple mixture of TiO and
3
.2. Photocatalytic Properties of NCTs
(
2
N
2
adsorption–desorption isotherms (Fig. 6(a)) show a well-
carbon (with the weight ratio equal to NCTs) indicates that the
UV–vis diffuse reflectance absorption spectrum of NCTs is not
merely the overlap of TiO
reversible adsorption and desoption step, indicating that NCTs
have a lager surface area. The BET specific surface area, pore
volume and pore area of the NCTs sample are 279.43 m /g,
2
2
and carbon black. From the CV spectra
(Fig. 6(c)), we can see that NCTs show a high re/oxidative current
peaks compared to P25, suggesting that NCTs exhibite better re/
oxidative ability and higher electrons transfer rate than P25
during chemical reaction [20].
In view of the high specific surface area, high chemical activity
and visible light sensitivity, herein, we performed photodegrada-
tion of RhB and photoreduction of K
2 2 7
Cr O to evaluate the visible
light ( : 400–2500 nm) photo-catalytic activity of NCTs. As
l
revealed by Fig. 6(d), RhB (40 ppm) can be removed completely
by NCTs within 3 h under visible light. Under the irradiation of
the tungsten-halogen with light filter, which produces visible
light ranged from 400 to 2500 nm. The photocatalytic pathway
can be summarized as follows: NCTs adsorbs photons and excites
electrons in the valence band to the conduction band, creating
highly reactive electron and hole pairs. Some of the pairs
recombine while some migrate to the NCTs surface to be involved
in the photocatalytic reaction. The electrons may be trapped by
ꢀ
oxygen to form oxygen species (
ꢁO
2
) (Fig. 8(b)). The photogen-
erated holes may be trapped by hydroxyl groups attached on the
surface to form hydroxyl radicals ( OH) (Fig. 8(a)). The holes,
together with hydroxyl radicals and oxygen species, oxidize the
ꢁ
Fig. 5. Scheme of the formation process of NCTs.
Fig. 6. (a) N
2
adsorption–desorption isotherm of NCTs; (b) UV–vis diffuse reflectance absorption spectra of P25, NCTs and physical mix; (c) CV spectra of P25 and NCTs;
Cr over P25 and NCTs.
(d) Photodegradation of RhB and K
2
2 7
O

3
10
H. Ming et al. / Journal of Solid State Chemistry 192 (2012) 305–311
Fig. 7. Reaction time dependence of the relative concentration of the RhB in solution over NCTs during repeated photodecomposition experiments.
RB in aqueous solution to carbon dioxide, water and some simple
mineral acids.
NCTs are also able to photoreduce Cr (IV) ions (50 ppm,
Chromium ion, one of the most toxic pollutants in water) within
1
.5 h under visible light in the presence of CHOONa, which acted
as an electron donor (Fig. 6(d), blue line) [21]. The ionic equations
for redox reaction are shown in Eqs. (1) and (2).
2
ꢀ
þ
ꢀ
3þ
Cr
2
O7 þ14H
3
O
þ6e 22Cr þ7H
2
O
ð1Þ
ð2Þ
ꢀ
þ
þ2eꢀ
HCOO þH
2
O2CO
2
þH
3
O
To test the repeatability of NCTs photocatalyst, photocatalytic
experiments were carried out ten times with the recycled photo-
catalysts. As shown in Fig. 7, NCTs are stable under repeated
application with nearly constant photo-decomposition rate.
We define the NCTs as a cosurface structure, where the
combination of two parts gives rise in synergistic properties
arising from the beneficial interaction between them. In other
words: the two components form a joint electronic system [5].
So there are three aspects (Fig. 8) together can explain why NCTs
with an appropriate composition can exhibit enhanced photo-
catalytic activity. Firstly, in a heterogeneous photo-catalysis
system, photoinduced molecular transformations or reactions
take place at the surface of a catalyst. For the advanced structure
and high surface areas of NCTs, NCTs can contack pollutants
sufficiently. Meanwhile, the substitutional doping of N was
effective because its p states contribute to the band-gap narrow-
ing by mixing with O 2p states. This factor leads to a charge
transfer between a dopant and a conduction or valence band,
consequently, giving rise to the red-shift in the band gap transi-
Fig. 8. Model picture demonstrating the electron transmission between carbon
film and TiO nanoparticles under visible-light irradiation and active species
during the photocatalysis process.
2
2
tion. So, N–TiO (2.16–3.2 eV) [22] irradiated by visible light
can generate a larger amount of photoreactive species such as
2
ꢀ
þ
O
, h and OH [9–11]. In order to elucidate the photoreactive
ꢁ
species, the effects of some scavengers on the degradation of RhB
were studied. The comparative experiment with no quencher was
also carried out under otherwise identical conditions. As a result
of quenching, photoreactive reaction will be partly suppressed
and Kapp is lowered. As shown in Fig. 9, it can be observed
Fig. 9. Kapp values of NCTs with different quenchers.
accounting for the efficient degradation of toxic organic pollution.
Secondly, N–Carbon in NCTs served as the electron reservoir and
transporter for effective charge separation and rapid transport of
that after the addition of isopropanol (IPA,
ꢁ
OH), benzoquinone
ꢀ
(
[
BQ,
ꢁ
O
2
scavenger) and ammonium oxalate (AO, hþ scavenger)
2
the photogenerated electrons emitted from N–TiO particles due to
ꢀ
23–26], the Kapp decreases obviously, which suggests that
OH and h are the main reactive species for the degradation of
ꢁO
2
,
light irradiation, which provided an stable electron source for
subsequent use in redox reactions and ensured a long live of holes
and electrons [5,11]. Thirdly, due to the partial carbonization of C
film and the doping of N, N–Carbon is considered to be a n-type
semiconductor with an apparent band gap of 2.2–3.0 eV [16,27,28],
þ
ꢁ
RhB. It is also comformed that a lot of potoactive species such
ꢀ
þ
as
ꢁ
O
2
, h and
ꢁOH produced in the photocatalytic process,
and these active species contacted with pollutant sufficiently,

H. Ming et al. / Journal of Solid State Chemistry 192 (2012) 305–311
311
which can photoresponse to visible light. Meanwhile, some elec-
trons transition process carried out between N–Carbon and N–TiO
conduction band [7]. Consequently, the appearance of excellent
visible photocatalytic activity over NCTs powders is reasonable.
[3] A.L. Linsebigler, G.Q. Lu, J.T. Yates, Chem. Rev. 95 (1995) 735–758.
[
[
4] A. Fujishima, K. Honda, Nature 238 (1972) 37–38.
5] Z. Li, X.F. Chen, X.C. Wang, Y.J. Zhang, W. Wei, Y.H. Sun, M. Antonietti,
M.M. Titirici, Adv. Mater. 22 (2010) 3317–3321.
2
[6] T. Sano, N. Negishi, K. Koike, K. Takeuchi, S. Matsuzawa, J. Mater. Chem.
4 (2004) 380–384.
1
[
7] Y.B. Tang, C.S. Lee, J. Xu, Z.T. Liu, Z.H. Chen, Z.B. He, Y.L. Cao, G.D. Yuan,
H.S. Song, L.M. Chen, L.B. Luo, H.M. Cheng, W.J. Zhang, I. Bello, S.T. Lee,
ACS Nano 4 (2010) 3482–3488.
4
. Conclusions
[
[
8] H.T. Li, X.D. He, Z.H. Kang, H. Huang, Y. Liu, J.L. Liu, S.Y. Lian, C.H.A. Tsang,
X.B. Yang, S.T. Lee, Angew. Chem. Int., Ed. 49 (2010) 4430–4434.
9] R. Asahi, T. Morikawa, T. Ohwaki, K. Aoki, Y. Taga, Science 293 (2001)
In summary, NCTs (5–10 nm N–TiO
N–Carbon) have been successfully synthesized by
2
evenly dispersed on
reflux
method. These NCTs have a large BET specific surface area of
a
269–271.
[
10] H. Ming, Z. Ma, H. Huang, S.Y. Lian, H.T. Li, X.D. He, H. Yu, K.M. Pan, Y. Liu,
2
2
79.43 m /g and show excellent photocatalytic abilities towards
Z.H. Kang, Chem. Commun. 47 (2011) 8025–8027.
organic (RhB) and inorganic pollutant (K Cr ) degradation
2
2 7
O
[11] C. Burda, Y.B. Lou, X.B. Chen, A.C.S. Samia, J. Stout, J.L. Gole, Nano Lett.
(2003) 1049–1051.
3
under visible light. NCTs can be separated and recycled by a
simple filtration process. Meanwhile, this cosurface N-doping
photocatalyst can keep stable photocatalytic activity after many
times reuse. This work provides a new approach for the high
performance catalyst design towards new energy sources and
environmental issues.
[12] X.B. Chen, Y.B. Lou, S. Dayal, X.F. Qiu, R. Krolicki, C. Burda, C.F. Zhao, J. Becker,
J. Nanosci. Nanotechnol. 5 (2005) 1408–1420.
[13] Y.Z. Zhang, S.H. Deng, B.Y. Sun, H. Xiao, L. Li, G. Yang, Q. Hui, J. Wu, J.T. Zheng,
J. Colloid Interface Sci. 347 (2010) 260–266.
[
14] Y. Wang, Y.Y. Shao, D.W. Matson, J.H. Li, Y.H. Lin, J. Am. Chem. Soc. 132 (2010)
274–9276.
[15] L.T. Qu, Y. Liu, J.B. Baek, L.M. Dai, ACS Nano 4 (2010) 1321–1326.
9
[
[
[
[
[
16] X.R. Wang, X.L. Li, L. Zhang, Y. Yoon, P.K. Weber, H.L. Wang, J. Guo, H.J. Dai,
Science 324 (2009) 768–771.
17] Z.H. Kang, E.B. Wang, B.D. Mao, Z.M. Su, L. Gao, S.Y. Lian, L. Xu, J. Am. Chem.
Soc. 127 (2005) 6534–6535.
18] W.J. Lee, J.M. Lee, S.T. Kochuveedu, T.H. Han, H.Y. Jeong, M. Park, J.M. Yun,
J. Kwon, K. No, D.H. Kim, S.O. Kim, ACS Nano 6 (2012) 935–943.
19] P. Leinweber, J. Kruse, F.L. Walley, A. Gillespie, K.U. Eckhardt, R.I.R. Blythc,
T. Regierc, J. Synchrotron Radiat. 14 (2007) 500–511.
Acknowledgements
This work is supported by the National Basic Research Program
of China (973 Program) (No. 2010CB934500), National Natural
Science Foundation of China (NSFC) (No. 51132006, 91027041,
20] C. Wang, H. Daimon, S.H. Sun, Nano Lett. 9 (2009) 1493–1496.
2
1073127, 21071104), A Foundation for the Author of National
[21] C.X. Yang, H.M. Yi, Biochem. Eng. J. 52 (2010) 160–167.
[
22] C.-C. Yen, D.-Y. Wang, L.-S. Chang, H.C. Shih, J. Solid State Chem. 184 (2011)
053–2060.
23] J. Bandara, J. Kiwi, New J. Chem. 23 (1999) 717–724.
Excellent Doctoral Dissertation of P R China (FANEDD) (No. 200929),
A Project Funded by the Priority Academic Program Development of
Jiangsu Higher Education Institutions (PAPD) and a Project sup-
ported by the Natural Science Foundation of the Jiangsu Higher
Education Institutions of China (Grant No. 11KJB150015).
2
[
[24] M.C. Yin, Z.S. Li, J.H. Kou, Z.G. Zou, Environ. Sci. Technol. 43 (2009)
361–8366.
8
[
[
[
25] L.S. Zhang, K.H. Wong, H.Y. Yip, C. Hu, J.C. Yu, C.Y. Chan, P.K. Wong, Environ.
Sci. Technol. 44 (2010) 1392–1398.
26] Y.X. Chen, S.Y. Yang, K. Wang, L.P. Lou, J. Photochem. Photobiol., A 172 (2005)
47–54.
References
27] P.K. Sitch, G. Jungnickel, T. Kohler, T. Frauenheim, D. Porezag, J. Non-Cryst.
Solids 607 (1998) 227–230.
[
[
1] X.B. Chen, S.S. Mao, Chem. Rev. 107 (2007) 2891–2959.
2] X.B. Chen, L. Liu, P.Y. Yu, S.S. Mao, Science 331 (2011) 746–750.
[28] X.C. Wang, K. Maeda, A. Thomas, K. Takanabe, G. Xin, J.M. Carlsson,
K.D.M. Antonietti, Nat. Mater. 8 (2009) 76–80.