TiO2 nanotubes (TiNTs)/graphite-like carbon nitride (g-C3N4) nanorod (NR) photocatalyst was synthesized by the droplet evaporation method followed by annealing. The aim of this research is to implement the environmental application of nanomaterial in terms of metal-free photocatalyst to treat organic pollutants. The as-prepared samples were characterized by X-ray powder diffraction, energy-dispersive spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, and UV–vis diffuse reflectance spectrometry. The results reveal that g-C3N4 NRs were decorated on TiNTs. Moreover, the photocatalytic performance of TiNTs/g-C3N4 NR composite under simulated solar light was measured for phenol as a test pollutant. The results of phenol degradation showed that the photocatalytic activity of TiNTs/g-C3N4 NR composite was higher than that of as-synthesized TiNTs under simulated light. Furthermore, the photocatalytic efficiency of the TiNTs/g-C3N4 NR composite was improved due to decrease in the charge transfer resistance and efficient transfer of photogenerated electron/hole pairs. The rate of photocatalytic reaction was determined from the pseudo first-order kinetics. Photocatalytic mechanism was proposed to explain the electron/hole separation and transport over the TiNTs/g-C3N4 NRs as well as phenol degradation under simulated light irradiation.
BaiX., WangL., ZongR., and ZhuY. (2013). Photocatalytic activity enhanced via g-C3N4 nanoplates to nanorods. J. Phys. Chem. C, 117, 9952.
3.
BakerD.R., and KamatP.V. (2009). Photosensitization of TiO2 nanostructures with CdS quantum dots: Particulate versus tubular support architectures. Adv. Funct. Mater. 19, 805.
4.
CavalcanteR.P., DantasR.F., WenderH., BayarriB., GonzálezO., GiménezJ., EsplugasS., and MachulekA. (2015). Photocatalytic treatment of metoprolol with B-doped TiO2: Effect of water matrix, toxicological evaluation and identification of intermediates. Appl. Catal. B Environ. 176, 173.
5.
ChenB., HouJ., and LuK. (2013). Formation mechanism of TiO2 nanotubes and their applications in photoelectrochemical water splitting and supercapacitors. Langmuir, 29, 5911.
6.
ChenY., HuangW., HeD., SituY., and HuangH. (2014). Construction of heterostructured g-C3N4/Ag/TiO2 microspheres with enhanced photocatalysis performance under visible-light irradiation. ACS Appl. Mater. Interf. 6, 14405.
7.
ChenZ., LiY., GuoM., XuF., WangP., DuY., and NaP. (2016). One-pot synthesis of Mn-doped TiO2 grown on graphene and the mechanism for removal of Cr(VI) and Cr(III). J. Hazard. Mater. 310, 188.
8.
FaisalM., IsmailA.A., HarrazF.A., Al-SayariS.A., El-ToniA.M., Al-SalamiA.E., and Al-AssiriM.S. (2018). Fabrication of highly efficient TiO2/C3N4 visible light driven photocatalysts with enhanced photocatalytic activity. J. Mol. Struct. 1173, 428.
9.
HaoR., WangG., JiangC., TangH., and XuQ. (2017). In situ hydrothermal synthesis of g-C3N4/TiO2 heterojunction photocatalysts with high specific surface area for rhodamine B degradation. Appl. Surf. Sci. 411, 400.
10.
JiangG., GengK., WuY., HanY., and ShenX. (2018). High photocatalytic performance of ruthenium complexes sensitizing g-C3N4/TiO2 hybrid in visible light irradiation. Appl. Catal. B Environ. 227, 366.
11.
LiH., RenF., LiuJ., WangQ., LiQ., YangJ., and WangY. (2015a). Endowing single-electron-trapped oxygen vacancy self-modified titanium dioxide with visible-light photocatalytic activity by grafting Fe(III) nanocluster. Appl. Catal. B Environ. 172, 37.
12.
LiX., PiY., XiaQ., Li., Q.Z., and XiaoJ. (2016). TiO2 encapsulated in salicylaldehyde-NH2 MIL-101(Cr) for enhanced visible light-driven photodegradation of MB. Appl. Catal. B Environ. 191, 192.
13.
LiX.H., ZhangJ., ChenX., FischerA., ThomasA., AntoniettiM., and WangX. (2011). Condensed graphitic carbon nitride nanorods by nanoconfinement: Promotion of crystallinity on photocatalytic conversion. Chem. Mater. 23, 4344.
14.
LiY., WangR., LiH., WeiX., FengJ., LiuK., DangY., and ZhouA. (2015b). Efficient and stable photoelectrochemical seawater splitting with TiO2@g-C3N4 nanorod arrays decorated by Co-Pi. J. Phys. Chem. C, 119, 20283.
15.
LiaoG., ChenS., QuanX., YuH., and ZhaoH. (2012). Graphene oxide modified g-C3N4 hybrid with enhanced photocatalytic capability under visible light irradiation. J. Mater. Chem. 22, 2721.
16.
LiuL., LuoC., XiongJ., YangZ., ZhangY., CaiY., and GuH. (2017). Reduced graphene oxide (rGO) decorated TiO2 microspheres for visible-light photocatalytic reduction of Cr(VI). J. Alloys Compd. 690, 771.
LuZ., ZengL., SongW., QinZ., ZengD., and XieC. (2017). In situ synthesis of C-TiO2/g-C3N4 heterojunction nanocomposite as highly visible light active photocatalyst originated from effective interfacial charge transfer. Appl. Catal. B Environ. 202, 489.
19.
LuoX., DengF., MinL., LuoS., GuoB., ZengG., and AuC. (2013). Facile one-step synthesis of inorganic-framework molecularly imprinted TiO2/WO3 nanocomposite and its molecular recognitive photocatalytic degradation of target contaminant. Environ. Sci. Technol. 47, 7404.
20.
MadhusudananS.P., GangajaB., ShylaA.G., NairA.S., Nair. S.V., and SanthanagopalanD. (2017). Sustainable chemical synthesis for phosphorus-doping of TiO2 nanoparticles by upcycling human urine and impact of doping on energy applications. ACS Sustain. Chem. Eng. 5, 2393.
21.
MaoL., WangY., ZhongY., NingJ., and HuY. (2013). Microwave-assisted deposition of metal sulfide/oxide nanocrystals onto a 3D hierarchical flower-like TiO2 nanostructure with improved photocatalytic activity. J. Mater. Chem. A, 1, 8101.
22.
PanC., XuJ., WangY., LiD., and ZhuY. (2012). Dramatic activity of C3N4/BiPO4 photocatalyst with core/shell structure formed by self-assembly. Adv. Funct. Mater. 22, 1518.
23.
ParkJ.T., KimD.J., KimD.H., and KimJ.H. (2017). A facile graft polymerization approach to N-doped TiO2 heterostructures with enhanced visible-light photocatalytic activity. Mater. Lett. 202, 66.
24.
PigattoG., LodiA., FinocchioE., PalmaM.S.A., and ConvertiA. (2013). Chitin as biosorbent for phenol removal from aqueous solution: Equilibrium, kinetic and thermodynamic studies. Chem. Eng. Proc. 70, 131.
25.
QiuJ., FengY., ZhangX., ZhangX., JiaM., and YaoJ. (2017). Facile stir-dried preparation of g-C3N4/TiO2 homogeneous composites with enhanced photocatalytic activity. RSC Adv. 7, 10668.
26.
RathiA.K., KmentováH., NaldoniA., GoswamiA., GawandeM.B., VarmaR.S., Kment, Š., and ZbořilR. (2018). Significant enhancement of photoactivity in hybrid TiO2/g-C3N4 nanorod catalysts modified with Cu–Ni-based nanostructures. ACS Appl. Nano. Mater. 1, 2526.
27.
SatoS., NakamuraR., and AbeS. (2005). Visible-light sensitization of TiO2 photocatalysts by wet-method N doping. Appl. Catal. A Gen. 284, 131.
28.
SunB., LuN., SuY., YuH., MengX., and GaoZ. (2017). Decoration of TiO2 nanotube arrays by graphitic-C3N4 quantum dots with improved photoelectrocatalytic performance. Appl. Surf. Sci. 394, 479.
29.
SunS., SunM., FangY., WangY., and WangH. (2016). One-step in situ calcination synthesis of g-C3N4/N-TiO2 hybrids with enhanced photoactivity. RSC Adv. 6, 13063.
30.
TanY., ShuZ., ZhouJ., LiT., WangW., and ZhaoZ. (2018). One-step synthesis of nanostructured g-C3N4/TiO2 composite for highly enhanced visible-light photocatalytic H2 evolution. Appl. Catal. B Environ. 230, 260.
31.
ThomasA., FischerA., GoettmannF., AntoniettiM., MüllerJ.-O., SchlöglR., and CarlssonJ.M. (2008). Graphitic carbon nitride materials: Variation of structure and morphology and their use as metal-free catalysts. J. Mater. Chem. 18, 4893.
32.
UllahS., Ferreira-NetoE.P., PasaA.A., AlcântaraC.C.J., AcuñaJ.J.S., BilmesS.A., Martínez RicciM.L., LandersR., FerminoT.Z., and Rodrigues-FilhoU.P. (2015). Enhanced photocatalytic properties of core@shell SiO2 @TiO2 nanoparticles. Appl. Catal. B Environ. 179, 333.
33.
VasudevanS. (2014). An efficient removal of phenol from water by peroxi-electrocoagulation processes. J. Water Proc. Eng. 2, 53.
34.
WeiX.-X., ChenC.-M., GuoS.-Q., GuoF., LiX.-M., WangX.-X., CuiH.-T., ZhaoL.-F., and LiW. (2014). Advanced visible-light-driven photocatalyst BiOBr–TiO2–graphene composite with graphene as a nano-filler. J. Mater. Chem. A, 2, 4667.
35.
WenliG., FeixueL., ChaoW., ShigenoriK., Lizhu, Wu., YongH., and MinW. (2017). Face-to-face interfacial assembly of ultrathin g-C3N4 and anatase TiO2 nanosheets for enhanced solar photocatalytic activity. ACS Appl. Mater. Interfaces, 9, 28674.
36.
XiaoL., LiuT., ZhangM., LiQ., and YangJ. (2018). Interfacial construction of zero-dimensional/one-dimensional g-C3N4 nanoparticles/TiO2 nanotube arrays with Z-scheme heterostructure for improved photoelectrochemical water splitting. ACS Sustain. Chem. Eng. 7, 2483.
37.
XieY., GuoS., GuoC., HeM., ChenD., JiY., ChenZ., WuX., LiuQ., and XieS. (2013). Controllable two-stage droplet evaporation method and its nanoparticle self-assembly mechanism. Langmuir, 29, 6232.
38.
XuJ., LiY., ZhouX., LiY., Da GaoZ., Yan SongY., and SchmukiP. (2016). Graphitic C3N4-sensitized TiO2 nanotube layers: A visible-light activated efficient metal-free antimicrobial platform. Chem. Eur. J. 22, 3947.
39.
XuL., XiaJ., WangL., JiH., QianJ., XuH., WangK., and LiH. (2014). Graphitic carbon nitride nanorods for photoelectrochemical sensing of trace copper(II) ions. Eur. J. Inorg. Chem. 2014, 3665.
40.
YanJ., WuH., ChenH., PangL., ZhangY., JiangR., LiL., and LiuS. (2016). One-pot hydrothermal fabrication of layered β-Ni(OH)2/g-C3N4 nanohybrids for enhanced photocatalytic water splitting. Appl. Catal. B Environ. 194, 74.
41.
YangK., MengC., LinL., PengX., ChenX., WangX., DaiW., and FuX. (2016). A heterostructured TiO2–C3N4 support for gold catalysts: A superior preferential oxidation of CO in the presence of H2 under visible light irradiation and without visible light irradiation. Catal. Sci. Technol. 6, 829.
42.
YeS., WangR., WuM.-Z., and YuanY.-P. (2015). A review on g-C3N4 for photocatalytic water splitting and CO2 reduction. Appl. Surf. Sci. 358, 15.
43.
YuL., WangL., SunX., and YeD. (2018a). Enhanced photocatalytic activity of rGO/TiO2 for the decomposition of formaldehyde under visible light irradiation. J Environ Sci. 73, 138.
44.
YuS., WangY., SunF., WangR., and ZhouY. (2018b). Novel mpg-C3N4/TiO2 nanocomposite photocatalytic membrane reactor for sulfamethoxazole photodegradation. Chem. Eng. J. 337, 183.
45.
ZhangG., ZhangT., LiB., JiangS., ZhangX., HaiL., ChenX., and WuW. (2018). An ingenious strategy of preparing TiO2/g-C3N4 heterojunction photocatalyst: In situ growth of TiO2 nanocrystals on g-C3N4 nanosheets via impregnation-calcination method. Appl. Surf. Sci. 433, 963.
46.
ZhangJ., ChenY., and WangX. (2015). Two-dimensional covalent carbon nitride nanosheets: Synthesis, functionalization, and applications. Energy Environ. Sci. 8, 3092.
47.
ZhangJ., ZhangM., YangC., and WangX. (2014a). Nanospherical carbon nitride frameworks with sharp edges accelerating charge collection and separation at a soft photocatalytic interface. Adv. Mater. 26, 4121.
48.
ZhangL., JingD., SheX., LiuH., YangD., LuY., LiJ., ShengZ., and GuoL. (2014b). Heterojunctions in g-C3N4/TiO2(B) nanofibres with exposed (001) plane and enhanced visible-light photoactivity. J. Mater. Chem. A. 2, 2071.
49.
ZhangY., LiuJ., WuG., and ChenW. (2012). Porous graphitic carbon nitride synthesized via direct polymerization of urea for efficient sunlight-driven photocatalytic hydrogen production. Nanoscale, 4, 5300.
50.
ZhengP., LiuT., SuY., ZhangL., and GuoS. (2016). TiO2 nanotubes wrapped with reduced graphene oxide as a high-performance anode material for lithium-ion batteries. Sci Rep. 6, 36580.
51.
ZhifengJ., ChengzhangZ., WeimingW., KunQ., and JiminX. (2016). Constructing graphite like carbon nitride modified hierarchical yolk–shell TiO2 spheres for water pollution treatment and hydrogen production. J. Mater. Chem. A, 4, 1806.
52.
ZhouX., NguyenN.T., ÖzkanS., and SchmukiP. (2014). Anodic TiO2 nanotube layers: Why does self-organized growth occur—a mini review. Electrochem. Commun. 46, 157.
53.
ZhuH., YangB., XuJ., FuZ., WenM., GuoT., FuS., ZuoJ., and ZhangS. (2009). Construction of Z-scheme type CdS–Au–TiO2 hollow nanorod arrays with enhanced photocatalytic activity. Appl. Catal. B Environ. 90, 463.
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