Synthesis and Photocatalytic Activity of Cerium-Modified CdS-TiO2 Photocatalyst for the Formaldehyde Degradation at Room Temperature

Article abstract of DOI:10.1002/zaac.201800315

The Ce-CdS-TiO₂ photocatalysts were successfully synthesized by a simple sol-gel way and loaded on the nickel foam. The specific surface area, crystalline phase, microstructure and surface functional groups of prepared photocatalysts were characterized by Brunauer-Emmett-Teller (BET) surface area, X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscope (TEM), and Fourier transform infrared spectroscopy (FT-IR). The photocatalytic tests of Ce-CdS-TiO₂ samples demonstrated that Ce as the active component plays an irreplaceable role in degradation of gaseous formaldehyde. The results showed that high Ce doping levels restrained the photocatalytic activity due to lower specific surface area, whereas moderate doping levels showed the highest photocatalytic performance due to higher specific surface area and evenly dispersion of the active component. The rate of formaldehyde degradation on 0.9 wt % Ce-CdS-TiO₂, 1.5 wt % Ce-CdS-TiO₂, and 2.1 wt % Ce-CdS-TiO₂ photocatalysts can reach to 59, 84, and 49 %, respectively, which are higher than pure TiO₂ (20 %). Ce-doping into CdS-TiO₂ photocatalyst produce the Ce-O-Ti bonds, which enhanced the interaction between Ce and TiO₂. The introduction of Ce increased the UV/Vis absorption of Ce-CdS-TiO₂ photocatalyst. Furthermore, Ce-CdS-TiO₂ possesses high photocatalytic performance, since Ce may reduce the recombination of photoexcited electrons and holes.

Full text of DOI:10.1002/zaac.201800315

Journal of Inorganic and General Chemistry
DOI: 10.1002/zaac.201800315
ARTICLE
Zeitschrift für anorganische und allgemeine Chemie
Synthesis and Photocatalytic Activity of Cerium-Modified CdS-
TiO2 Photocatalyst for the Formaldehyde Degradation at Room
Temperature
Junliang Xie,,[a][‡] Wei Hong,,[a][‡] Mianwu Meng,*[a] Mengke Tian,[a] Caiyan Kang,[a] Zhenming Zhou,[a]
Chaoshu Chen,[a] Yuhong Tang,[a] and Guangyu Luo[a]
Abstract. The Ce-CdS-TiO2 photocatalysts were successfully synthe- face area, whereas moderate doping levels showed the highest photo-
sized by a simple sol-gel way and loaded on the nickel foam. The
specific surface area, crystalline phase, microstructure and surface dispersion of the active component. The rate of formaldehyde degrada-
functional groups of prepared photocatalysts were characterized by tion on 0.9 wt% Ce-CdS-TiO2, 1.5 wt% Ce-CdS-TiO2, and 2.1 wt%
Brunauer-Emmett-Teller (BET) surface area, X-ray diffraction (XRD), Ce-CdS-TiO2 photocatalysts can reach to 59, 84, and 49%, respec-
scanning electron microscopy (SEM), transmission electron micro- tively, which are higher than pure TiO2 (20%). Ce-doping into CdS-
scope (TEM), and Fourier transform infrared spectroscopy (FT-IR). TiO2 photocatalyst produce the Ce-O-Ti bonds, which enhanced the
The photocatalytic tests of Ce-CdS-TiO2 samples demonstrated that interaction between Ce and TiO2. The introduction of Ce increased the
catalytic performance due to higher specific surface area and evenly
Ce as the active component plays an irreplaceable role in degradation UV/Vis absorption of Ce-CdS-TiO2 photocatalyst. Furthermore, Ce-
of gaseous formaldehyde. The results showed that high Ce doping CdS-TiO2 possesses high photocatalytic performance, since Ce may
levels restrained the photocatalytic activity due to lower specific sur- reduce the recombination of photoexcited electrons and holes.
synergistic effect of photocatalysis and photo-Fenton reactions.
1 Introduction
Lourenco et al.[14] synthesized TiO2 that supported on glass
Formaldehyde released by wood-based panels, coating, and
can remove ethylene in fruit storage environment efficiently
paints is one of the indoor main organic pollutants.[1–3] Mean-
under closed air circulation system and UV-A lamp irradiation.
while, formaldehyde is harmful to indoor air quality and hu-
Unfortunately, pure TiO2, without any doping or modification,
man’s health due to photochemical and carcinogenic character-
possesses only weak photocatalytic performance, because of
istics.[4] It is reported that the formaldehyde concentration in
fast restructuring of photoexcited electron-hole pairs and poor
many indoor typical places exceed WHO thresholds (δ =
0.08 ppm).[5] Therefore, to control the gaseous formaldehyde
utilization of solar energy (3–5% of the solar energy).[15–18]
Thus, it is a challenge to increase the light absorption of TiO2
in indoor environment has become a hot issue and received
and separation of photoexcited electron and hole.
widespread attention from researchers. The technologies of re-
For this reason, introduction of semiconductors with narrow
moving formaldehyde include catalytic oxidation,[6] physical
bandgap to TiO2 seems to be a promising approach to enhance
adsorption,[7] plants purification, and photocatalytic degrada-
the photocatalytic activity under the visible light.[19–21] CdS,
tion.[8–10] Among them, the photocatalytic degradation of
which possess ability of absorption and utilization visible light
HCHO to nontoxic products by semiconductor materials is a
less than 520 nm wavelengths is an ideal narrow bandgap
most prospect technology, because it can not only remove low
concentration HCHO at ppb/ppm level, but also react with
HCHO at room temperature using light and air.[11]
semiconductor.[22,23] Zhao et al.[24] reported the meso-macro-
porous TiO2/CdS photocatalyst possessed higher photocata-
lytic activity, owing to the enhancing charge transfer efficiency
at TiO2/CdS interface. Some literature reported that doping
Since the Fujishima and Hongda discovered photoelectroch-
emical phenomena on n-TiO2 electrodes in 1972,[12] TiO2 has
CdS to TiO2 can enhance photocatalytic activity under ultravi-
long been the most popular semiconductor material in air puri-
olet and visible light, which is due to formation heterojunction
fication, water treatment, sterilization, and disinfection due to
between CdS and TiO2.[25,26] However, the photocatalytic per-
its lower cost, non-toxicity, and high photochemical stability.
formance of CdS/TiO2 often suffered from fast restructuring
Sun et al.[13] prepared ferric tartrate modification TiO2 nanotu-
of photoexcited electron-hole pairs, which caused the instabil-
bes with excellent photocatalytic activity of methyl orange de-
ity and poor photocatalytic activity.[27,28] Hence, decrease the
gradation under UV/Vis light irradiation, which is due to the
recombination of photoexcited electron-hole pairs of CdS/TiO2
still remains a challenge.
* Dr. M. Meng
In recent years, doping noble metal on CdS/TiO2 photocata-
lyst has attracted much attention of researchers, which act as
a role facilitating photoexcited electrons separation. For exam-
ple, Nguyen et al.[29] demonstrated that the CdS/Au/TiO2 NTA
E-Mail: mmwmmw@mailbox.gxnu.edu.cn
[a] College of Environment and Resource
Guangxi Normal University
Guilin 541000, P. R. China
[‡] These authors contributed equally.
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and speed of 2°·min. The specific surface areas of samples were ob-
photocatalyst possessed highly photocatalytic activity due to
tained by the N2 adsorption method and calculated by Brunauer–Em-
mett–Teller method. The microstructures of catalysts were gained by
scanning electron microscope (FEI Quanta 200 FEG). Transmission
electron microscope (TEM) images were analyzed with a Tecnai G2
F20 microscopy. The photocatalyst of infrared spectra were obtained
with a Fourier transform infrared spectrometer. The UV/Vis absorption
spectra were tested with a TU-1901 model dual beam visible photome-
ter.
Au facilitating photoexcited electrons separation. But the high
cost of the noble metal limits its industrial application. Some
literatures reported that Ce possesses the function of facilita-
ting photoexcited electrons separation and increasing light ab-
sorption.[30–32] Vieira et al.[33] prepared CeO2/TiO2 photocata-
lyst by hydrothermal with great photocatalytic activity for
reason that Ce doping into TiO2 enhanced the light utilization
efficiency. To our best knowledge, the photocatalyst of Ce-
CdS-TiO2 has not been reported in previous literature. We de-
signed a novel photocatalyst for degradation of formaldehyde.
Furthermore, the function of Ce is studied in the Ce-CdS-TiO2
structure.
In this paper, the behaviors of various Ce/Ti mass ratios on
the performance of Ce-CdS-TiO2 catalysts are researched. The
purposes of the presented study is the preparation of Ce-CdS-
TiO2 photocatalysts, then the photocatalytic mechanism of
formaldehyde degradation over Ce-CdS-TiO2 is discussed
based on the Ce-CdS-TiO2 microstructure, crystalline phase,
and surface functional groups results.
2.4 Photocatalytic Activities
The samples photocatalytic activities tests were carried out in glass
reactor (0.6 mϫ0.6 mϫ0.5 m), and the concentration of formalde-
hyde in reactor was measured with a PPM-400ST formaldehyde detec-
tor. The sample was put at the bottom of reactor and the glass reactor
placed in the dark room. Formaldehyde gas was injected into reactor
by bubbling method and the initial concentration of formaldehyde was
approximately 0.5 ppm. The 6 W LED light [emitting ultraviolet light
(368 nm) and visible light] was placed 15 cm from the sample. In ad-
dition, the concentration of formaldehyde in the chamber was mea-
sured every 30 min and the whole photocatalytic activity experiment
lasted 5 h.
2 Experimental Section
3 Result and Discussion
2.1 Materials
3.1 Photocatalysts Performance
The reagents include paraformaldehyde (AR; Tianjin Guangfu Fine
Chemical Research institute), anhydrous ethanol (AR; Guangdong
Chemical reagents), sodium silicate (CP; Guangdong Chemical Rea-
gent Factory), butyl titanate (CP; Tianjin Guangfu), polyethylene
glycol 600 (CP; Xilong chemical), cerium nitrate (AR; Xilong chemi-
cal), cadmium nitrate (AR; Xilong chemical), glacial acetic acid (AR;
Tianjin Guangfu), and thiourea (AR; Tianjin North Medical Pharma-
ceutical Factory). All reagents were used without further purification.
Figure 1 exhibits formaldehyde photocatalytic oxidation
performance of pure TiO2, CdS-TiO2, and (0.9 wt%, 1.5 wt%,
2.1 wt%) Ce-CdS-TiO2. In the blank experiment result without
photocatalyst, the natural attenuation of formaldehyde after 5
h was approximately 5%, indicating that the LED light has
trifling effect on the formaldehyde degradation. The pure TiO2
exhibited the lowest formaldehyde degradation effect (ca.
20%) without any introduction. The degradation effect of CdS-
TiO2 photocatalyst increased to 39% after doping CdS. When
the Ce was introduced, all of Ce-CdS-TiO2 samples revealed
higher degradation effect than pure TiO2 and CdS-TiO2. In
addition, the degradation effect of Ce-CdS-TiO2 photocatalyst
increased first and then decreased with increasing of the ce-
rium content. The sample of 1.5 wt% Ce-CdS-TiO2 reveals the
highest formaldehyde degradation effect (ca. 84%). This result
2.2 Synthesis of Photocatalyst
In this experiment, Ce-CdS-TiO2 photocatalyst was synthesized by a
sol-gel method. Butyl titanate (98% purity), anhydrous ethanol (99.9%
purity), glacial acetic acid (99.5% purity), polyethylene glycol 600
(99.9% purity), and distilled water with a ratio of 3:7:1.3:0.5:0.1 was
mingled and stirred for 30 min. During the stirring process, the 0.01 m
CdS (synthesis by cadmium nitrate and thiourea with a 1:1 molar ratio)
was first added to the solution, and after dissolution, the various con-
tent of cerium nitrate [the mass ratios of Ce(NO3)3·6H2O/butyl titanate
were 0.9 wt%, 1.5 wt%, 2.1 wt%, catalyst was named xCe-CdS-TiO2]
was added to the solution. The mixed solutions were placed in a water
bath at 90 °C for 2 h to form sol. Afterwards the sol was dried in air
at 100 °C for 3 h. After cooling to room temperature, the samples were
ground to powder and calcined in air at 475 °C for 3 h. The Ce-CdS-
TiO2 photocatalytic films were obtained by an impregnation method.
The calcined samples were mixed with 20wt% silicate solution and
ultrasonicated for 20 min to prepared suspensions. The nickel foams
(4 cmϫ4 cm) were placed in suspension for 10 min, and finally the
nickel foams were dried at 100 °C.
2.3 Characterization
The X-ray diffraction patterns were analyzed by X-ray diffractometer
Figure 1. Photocatalytic performance of different photocatalysts under
(D/max2500v/pc) under condition of Cu-Kα irradiation source, 30 kV LED irradiation.
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indicated that the moderate introduction of Ce is beneficial to crystals. With the Ce amount increasing, no crystal signal
the photocatalytic effect of Ce-CdS-TiO2 catalysts. At the about cerium appears in the samples of 0.9 wt% Ce-CdS-TiO2,
same time, in order to estimate the stability of 1.5 wt% Ce- 1.5 wt% Ce-CdS-TiO2, and 2.1 wt% Ce-CdS-TiO2, which in-
CdS-TiO2, it was evaluated by a recycling experiment. As is dicates that Ce probably exists in the form of ionic or forms a
shown in Figure 2, after 10 repeated experiments, the formal- highly dispersed phase on the photocatalyst surface.[39,40] The
dehyde degradation activity decreased slightly. Experiments crystallization peaks of anatase TiO2 are obviously weakened
showed that 1.5 wt% Ce-CdS-TiO2 photocatalyst possessed and broadened with the introduction of CdS, indicating that
better stability and repeatability.
CdS restrains the formation of TiO2 crystals. The intensity of
the crystalline peaks of CdS slightly enhanced when the
Ce(NO3)3·6H2O/butyl titanate mass ratio was 1.5 wt%.[41,42]
However, when the Ce(NO3)3·6H2O/butyl titanate mass ratio
was 2.1 wt%, the pattern of Ce-CdS-TiO2 showed a weak dif-
fraction peak at 2θ = 25.28, and the results of the performance
test showed that the photocatalytic performance of the catalyst
was adversely affected by reduced crystallinity.[43]
3.3 Fourier Transform Infrared Spectroscopy Spectra
FT-IR spectra of pure TiO2, CdS-TiO2, and various Ce/Ti
mass ratios Ce-CdS-TiO2 photocatalysts are illustrated in Fig-
ure 4. The spectra of CdS-TiO2 and 1.5 wt% Ce-CdS-TiO2
photocatalyst materials show absorption bands at 613 cm–1 and
1111 cm–1, which correspond to the bending vibrations of Cd–
S bonds.[44,45] The peaks at 1648 cm–1 and 3440 cm–1 are as-
signed to the physically absorption water and –OH stretching
and bending vibrations.[46] For the 1.5 wt% Ce-CdS-TiO2 pho-
tocatalyst the FT-IR spectrum is shown in Figure 4c; the new
peak at near 478 cm–1 can be attributed to the stretching vi-
bration of Ce–O–Ti bonds.[47] It can be seen that Ce is success-
fully fixed on the TiO2 surface, which is accordance with XRD
results.
Figure 2. Repeat times of the 1.5 wt% Ce-CdS-TiO2.
3.2 Crystal Structure
The X-ray diffraction pattern of pure TiO2, CdS-TiO2, and
(0.9 wt%, 1.5 wt%, 2.1 wt%) Ce-CdS-TiO2 samples are ex-
hibited in Figure 3. The diffraction peaks of pure TiO2 are
completely matched with the standard anatase TiO2 (JCPDS
No.21–1272).[34,36] After doping the CdS, the peaks at 24.8°,
47.9°, and 51.9° correspond to (100), (103), and (112) hexahe-
dron crystalline planes of CdS (JCPDS No.41–1049), whereas
the reflection at 30.7° corresponds to (200) cubic crystalline
planes of CdS (JCPDS No.42–1411).[35,37,38] The new appear-
ing diffraction peaks at 27.5° and 36.2° correspond to (110)
and (101) rutile crystal planes of TiO2 (JCPDS No.21–1276)
[34]
after introduction of CdS and Ce, indicating that the intro-
duction of Ce and CdS promotes the formation of TiO2 rutile
Figure 4. The FT-IR spectrums of pure TiO2 (a), 0.9 wt% Ce-CdS-
TiO2 (b), 1.5 wt% Ce-CdS-TiO2 (c), 2.1 wt% Ce-CdS-TiO2 (d), and
CdS-TiO2 (e).
3.4 Specific Surface Area Result
Table 1 summarizes the specific surface area of pure TiO2,
CdS-TiO2, and (0.9 wt%, 1.5 wt%, 2.1 wt%) Ce-CdS-TiO2
photocatalysts. It can be seen that the introduction of cerium
can obviously increase the specific surface area of catalysts.[33]
Especially, the 1.5 wt% Ce-CdS-TiO2 sample possessed the
Figure 3. X-ray diffraction pattern of pure TiO2, CdS-TiO2, and
(0.9 wt%, 1.5 wt%, 2.1 wt%) Ce-CdS-TiO2.
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highest specific surface area (39.94 m2·g–1), which is more
than six times of pure TiO2 (6.40 m2·g–1). It has been shown
in previous literature that catalysts with a larger specific sur-
face area could provide more active sites, thereby the catalyst
exhibit better photocatalytic activity.[48,49] As shown in
Table 1, the 1.5 wt% Ce-CdS-TiO2 sample exhibited highest
photocatalytic performance probably due to its larger specific
surface area (39.94 m2·g–1) than the other four catalysts. In
addition, the specific surface area of Ce-CdS-TiO2 decreased
with the Ce amount increasing, indicating that the contact be-
tween Ce and TiO2 may be reduced.[33]
Table 1. Specific surface area of the catalysts.
Catalyst
BET surface area /m2·g–1
Pure TiO2
6.396
CdS-TiO2
25.172
29.585
39.941
28.311
0.9 wt% Ce-CdS-TiO2
1.5 wt% Ce-CdS-TiO2
2.1 wt% Ce-CdS-TiO2
3.5 Morphology and Microstructure
The SEM images of pure TiO2, CdS-TiO2, and (0.9 wt%,
1.5 wt%, 2.1 wt%) Ce-CdS-TiO2 are revealed in Figure 5. It
can be seen that different amounts of Ce(NO3)3·6H2O have an
obvious effect for the morphology of the Ce-CdS-TiO2 photo-
catalysts. Analyzing the pure TiO2 morphology (Figure 5a),
the sample showed irregular, smooth surface and distinct out-
line massive microstructure with an average size of 6.7 μm.
After CdS recombination (Figure 5b), the microstructure of
TiO2 was not changed, at the same time lamellar CdS sediment
appears on the surface of TiO2.[50] After the introduction of
cerium, the Ce-CdS-TiO2 surface changed significantly. When
Ce(NO3)3·6H2O/butyl titanate mass ratio was 0.9 wt%, the
synthesized Ce-CdS-TiO2 surface appeared more lamellar sed-
iment with a size of 4.77 μm. As the mass ratio increases to
1.5 wt%, the sample of Ce-CdS-TiO2 surface transferred from
smooth to rough with their average size reduced to 4.06 μm.
This result demonstrates that the introduction of Ce to CdS-
TiO2 catalysts can decrease the size of photocatalysts. Further-
more, in the report of Zhang et al.[51,52] small particle could
offer more excited sites for reagents. The surface of TiO2
changed rougher when doping 1.5 wt% mass of Ce(NO3)
3·6H2O (Figure 5d), which means that the TiO2 surface was
densely covered by Ce, and this phenomenon may enhance the
pollution adsorption of catalyst.[53] However, the Ce loaded on
the TiO2 surface in form of aggregates when the doping
amount was increased to 2.1 wt% (Figure 5e), and the average
size of photocatalyst enlarged to 5.38 μm.
Figure 5. SEM image of pure TiO2 (a), CdS-TiO2 (b), and (0.9 wt%,
1.5 wt%, 2.1 wt%) Ce-CdS-TiO2 (c, d, e).
(200) plane of CdS and the (101) plane of TiO2, respec-
tively.[35,55] The results show that Ce and CdS coexist in the
Ce-CdS-TiO2 catalyst, which is consistent with the results of
XRD and SEM.
3.6 UV/Vis Spectra of Samples
Figure 7 shows the UV/Vis absorption spectrums of pure
TiO2, CdS-TiO2, and 1.5 wt% Ce-CdS-TiO2 powder samples.
It is found that the absorption edge of 1.5 wt% Ce-CdS-TiO2
is ca. 300 nm, and with the introduction of Ce, the UV/Vis
absorption intensity of Ce-CdS-TiO2 is higher than pure TiO2
and CdS-TiO2, indicating that the introduction of Ce was bene-
ficial to improve the photocatalytic of Ce-CdS-TiO2. Further-
more, the CdS-TiO2 photocatalyst doping with Ce showed no
declines during the scope of 420–530 nm, which is probably
attributed to the existence of a solid solution between Ce and
TiO2.[56,57]
In order to further investigate the hetero-structure in the Ce-
CdS-TiO2 material, the 1.5 wt% Ce-CdS-TiO2 powder sample
was researched by TEM and HRTEM, and the results are
shown in Figure 6. The 1.5 wt% Ce-CdS-TiO2 sample re-
vealed twin boundaries due to the presence of Ce on the TiO2
surface.[54] Figure 6b illustrates the lattice fringe of 1.5 wt%
Ce-CdS-TiO2 photocatalyst. The lattice spacing marked in Fig-
TiO2 + hν Ǟ (TiO2)e– + (TiO2)h+
CdS + hν Ǟ (CdS)e– + (CdS)h+
(CdS)e– + Ce4+ Ǟ Ce3+
(1)
(2)
(3)
(4)
ure 6b is 0.29 nm and 0.35 nm, which was consistent with the (TiO2)e– + Ce4+ Ǟ Ce3+
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Figure 8. Photocatalytic mechanism of formaldehyde degradation over
Ce-CdS-TiO2.
over Ce-CdS-TiO2 photocatalyst is described in Figure 8. The
electrons and holes are produced by CdS and TiO2 under ultravi-
olet and visible irradiation [Equation (1), Equation (2)], then the
electrons are transferred fast from conduction band to Ce ions
[Equation (3), Equation (4)]. Meanwhile, the unstable Ce3+,
which is formed by Ce4+ acceptance electron, transfers an elec-
Figure 6. (a) The TEM image and (b) HRTEM image of 1.5 wt% Ce-
CdS-TiO2.
–
tron to O2 forming superoxide radicals (•O2 ) [Equation (5)].
Moreover, the holes produced by CdS and TiO2 react with the
adsorbed H2O to produce hydroxyl radicals (•OH) [Equation (6),
•
Equation (7)]. The previous literature reported that OH and
•O2– were the main reactive oxygen species in the photocatalytic
process.[62–65] The •OH and •O2– produced in the above photo-
catalytic process would react with formaldehyde and effectively
degrade them [Equation (8)]. Therefore, the introduction of Ce
can improve the CdS-TiO2 photocatalytic performance and sta-
bility.
4 Conclusions
The Ce-CdS-TiO2 photocatalyst supporting on nickel foam
was successfully prepared by a sol-gel method. It was found that
Ce has a significant role in the process of degradation formalde-
hyde. The characterization results of Ce-modified samples ex-
hibited the ideal specific surface area, especially the catalyst re-
vealed the highest specific surface area (39.94 m2·g–1) when the
ratio of Ce(NO3)3·6H2O/butyl titanate was 1.5 wt%. In the
meantime, the introduction of Ce increased the UV/Vis absorp-
tion of Ce-CdS-TiO2 photocatalyst. The activity test showed ex-
cellent efficiency of formaldehyde degradation (83.42%) over
Ce-CdS-TiO2 catalyst when the content of Ce(NO3)3·6H2O was
1.5 wt%. Furthermore, the result of recycling experiments dem-
onstrated the 1.5 wt% Ce-CdS-TiO2 photocatalyst possessed
excellent photocatalytic stability. In summary, Ce-CdS-TiO2
novel catalytic material with great application prospects because
of their high efficiency and stability of photocatalysis.
Figure 7. UV/Vis absorption spectrums of samples.
•
–
Ce3+ + O2 Ǟ Ce4+ + O2
(5)
(6)
(7)
(8)
•
(TiO2)h+ + H2O Ǟ OH
•
(CdS)h+ + H2O Ǟ OH
–
•
•O2 or OH + HCHO Ǟ CO2 + H2O + degradation products
3.7 Photocatalytic Mechanism
The Ce ions can capture photoexcited electrons better than
oxygen molecules described in the literature.[35,58–61] On the ba-
sis of the above results (Figure 1, Figure 2, and Figure 6), a feas-
Acknowledgements
Grateful acknowledge the support of the National Natural Science
ible mechanism and schematic for formaldehyde degradation Foundation of China (No. 21467002); Innovation Project of Guangxi
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ARTICLE
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[32] M. H. Cao, P. F. Wang, Y. H. Ao, C. Wang, J. Hou, J. Qian, J.
Graduate Education (YCSW2018090); and Key Laboratory of Ecology
Colloid Interface Sci. 2016, 467, 129.
Rare and Endangered Species and Environmental Protection (Guangxi
Normal University), Ministry of Education, China (grant numbers
ERESEP2017Z05).
[33] G. B. Vieira, H. J. Jose, M. Peterson, V. Z. Baldissarelli, P. Alva-
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Keywords: Photocatalysis; Ce-CdS-TiO2; Cerium; Sol-gel
method; Formaldehyde degradation
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Published online: ᭿
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© 0000 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

Journal of Inorganic and General Chemistry
ARTICLE
Zeitschrift für anorganische und allgemeine Chemie
J. Xie, W. Hong, M. Meng*, M. Tian, C. Kang, Z. Zhou,
C. Chen, Y. Tang, G. Luo ................................................. 1–8
Synthesis and Photocatalytic Activity of Cerium-Modified
CdS-TiO2 Photocatalyst for the Formaldehyde Degradation at
Room Temperature
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