Hematite/Graphitic Carbon Nitride Nanofilm for Fenton and Photocatalytic Oxidation of Methylene Blue

Hematite (α-Fe2O3)/graphitic carbon nitride (g-C3N4) nanofilm catalysts were synthesized on fluorine-doped tin oxide glass by hydrothermal and chemical vapor deposition. Scanning electron microscopy, energy-dispersive spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopy analyses of the synthesized catalyst showed that the nanoparticles of g-C3N4 were successfully deposited on α-Fe2O3 nanofilm. The methylene blue degradation efficiency of the α-Fe2O3/g-C3N4 composite catalyst was 2.6 times greater than that of the α-Fe2O3 single catalyst under ultraviolet (UV) irradiation. The methylene blue degradation rate by the α-Fe2O3/g-C3N4 catalyst increased by 6.5 times after 1 mM of hydrogen peroxide (H2O2) was added. The photo-Fenton reaction of the catalyst, UV, and H2O2 greatly increased the methylene blue degradation. The results from the scavenger experiment indicated that the main reactants in the methylene blue decomposition reaction are superoxide radicals photocatalytically generated by g-C3N4 and hydroxyl radicals generated by the photo-Fenton reaction. The α-Fe2O3/g-C3N4 nanofilm showed excellent reaction rate constants at pH 3 (Ka = 6.13 × 10−2 min−1), and still better efficiency at pH 7 (Ka = 3.67 × 10−2 min−1), compared to other methylene blue degradation catalysts. As an immobilized photo-Fenton catalyst without iron sludge formation, nanostructured α-Fe2O3/g-C3N4 are advantageous for process design compared to particle-type catalysts.

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Preparation of sodium and boron co-doped graphitic carbon nitride for the enhanced production of H2O2 via two-electron oxygen reduction and the degradation of 2,4-DCP via photocatalytic oxidation coupled with Fenton oxidation

Chemical Engineering Journal ◽

10.1016/j.cej.2021.134020 ◽

2022 ◽

Vol 431 ◽

pp. 134020

Author(s):

Yanyang Chu ◽

Xianglei Zheng ◽

Jinruo Fan

Keyword(s):

Oxygen Reduction ◽

Photocatalytic Oxidation ◽

Carbon Nitride ◽

Graphitic Carbon ◽

Fenton Oxidation ◽

Graphitic Carbon Nitride ◽

Enhanced Production ◽

Co Doped

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Visible-light enhancement of methylene blue photodegradation by graphitic carbon nitride-titania composites

Materials Science in Semiconductor Processing ◽

10.1016/j.mssp.2014.08.004 ◽

2014 ◽

Vol 27 ◽

pp. 966-974 ◽

Cited By ~ 15

Author(s):

Dongying Fu ◽

Gaoyi Han ◽

Feifei Liu ◽

Yaoming Xiao ◽

Hongfei Wang ◽

...

Keyword(s):

Methylene Blue ◽

Visible Light ◽

Carbon Nitride ◽

Graphitic Carbon ◽

Graphitic Carbon Nitride ◽

Light Enhancement

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Graphitic carbon nitride modified with Pd nanoparticles toward efficient cathode catalyst for Li-O2 batteries

Functional Materials Letters ◽

10.1142/s1793604720510455 ◽

2020 ◽

Vol 13 (07) ◽

pp. 2051045

Author(s):

Kaicheng Yue ◽

Zhaoqian Yan ◽

Zhihao Sun ◽

Anran Li ◽

Lei Qian

Keyword(s):

Electron Microscope ◽

Current Density ◽

Carbon Nitride ◽

Specific Capacity ◽

Pd Nanoparticles ◽

Graphitic Carbon ◽

Graphitic Carbon Nitride ◽

Cathode Catalyst ◽

X Ray ◽

Cathode Catalysts

In this work, graphitic carbon nitride (g-C3N4) was modified by Pd nanoparticles (Pd-CN) to prepare an efficient cathode catalyst for Li-O2 batteries. The specific surface area of g-C3N4 was improved to 239.56[Formula: see text]m2/g by two-steps thermal polymerization. Pd nanoparticles were loaded onto the g-C3N4 by K2PdCl4 reduction with NaBH4. The resulted Pd-CN composites were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, field emission scanning electron microscope, and transmission electron microscope. The results proved that g-C3N4 showed three-dimensional layered and porous structure, and Pd nanoparticles were successfully supported on it. The Li-O2 batteries using Pd-CN composites as cathode catalysts were assembled and tested. The maximum initial discharge specific capacity reached 26,614[Formula: see text]mAh[Formula: see text]g[Formula: see text] at current density of 100[Formula: see text]mA[Formula: see text]g[Formula: see text]. The electrodes remained large capacity under high current density, meaning excellent rate capability. Li-O2 batteries containing Pd-CN cathode were continuously cycled for 70 cycles with no loss of capacity and obvious change in the terminal voltage. These electrochemical results indicated that the loading Pd nanoparticles effectively increased specific capacity, reduced overpotential and improved the cyclic stability. The Pd-CN composites are proved to be the promising cathode catalysts for Li-O2 batteries.

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Zirconia nanoparticle-modified graphitic carbon nitride nanosheets for effective photocatalytic degradation of 4-nitrophenol in water

Applied Water Science ◽

10.1007/s13201-019-1076-8 ◽

2019 ◽

Vol 9 (8) ◽

Cited By ~ 5

Author(s):

Mohanna Zarei ◽

Jamil Bahrami ◽

Mohammad Zarei

Keyword(s):

Photocatalytic Activity ◽

Photocatalytic Degradation ◽

Carbon Nitride ◽

Diffuse Reflectance Spectroscopy ◽

Graphitic Carbon ◽

Graphitic Carbon Nitride ◽

X Ray Diffraction ◽

X Ray ◽

Zirconia Nanoparticle ◽

Carbon Nitride Nanosheets

Abstract Zirconia (ZrO2)-modified graphitic carbon nitride (g-C3N4) nanocomposite was used for effective photodegradation of 4-nitrophenol (4-NP) in water. The ZrO2 nanoparticles, g-C3N4 nanosheets, and ZrO2/g-C3N4 nanocomposite were well characterized by including N2 adsorption, X-ray diffraction, Fourier transform infrared spectroscopy, field emission scanning electron microscopy, UV–Vis diffuse reflectance spectroscopy, photoelectrochemical measurements, and photoluminescence spectroscopy methods. ZrO2/g-C3N4 nanocomposites were formed at room temperature using sonication and used for effective for photodegradation of 4-NP under irradiation with visible light. The nanocomposite samples resulted in a significant increase in photocatalytic activity compared with single-component samples of g-C3N4. In particular, the ZrO2/g-C3N4 nanocomposite exhibited the significant increase in the photocatalytic activity. The ZrO2/g-C3N4 nanocomposite showed an excellent catalytic activity toward the reduction of 4-NP in aqueous medium. Further, ZrO2/g-C3N4 nanocomposite can be reused several times for photocatalytic degradation as well as for 4-NP adsorption.

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Preparation of Nitrogen-Deficient Graphitic Carbon Nitride with a Large Specific Surface Area by Melt Pretreatment and Its Photocatalytic Performance

NANO ◽

10.1142/s1793292020500794 ◽

2020 ◽

Vol 15 (06) ◽

pp. 2050079

Author(s):

Xuelei Li ◽

Jinfeng Bai ◽

Jiaqi Li ◽

Chao Li ◽

Junru Zhang ◽

...

Keyword(s):

Visible Light ◽

Specific Surface ◽

Surface Area ◽

Specific Surface Area ◽

Carbon Nitride ◽

Mesoporous Structure ◽

Graphitic Carbon ◽

Graphitic Carbon Nitride ◽

Large Specific Surface Area ◽

X Ray

In this study, nitrogen-deficient graphitic carbon nitride (M-LS-g-C3N4) with a mesoporous structure and a large specific surface area was obtained by calcination after melt pretreatment using urea as a precursor. X-ray diffraction (XRD), transmission electron microscopy (TEM), N2 adsorption, X-ray photoelectron spectroscopy (XPS), UV-Vis, ESR and photoluminescence (PL) were used to characterize the structure, morphology and optical performance of the samples. The TEM results showed the formation of a mesoporous structure on the 0.1[Formula: see text]M-LS-g-C3N4 surface. The porous structure led to an increase in the specific surface area from 41.5[Formula: see text]m2/g to 124.3[Formula: see text]m2/g. The UV-Vis results showed that nitrogen vacancies generated during the modification process reduced the band gap of g-C3N4 and improved the visible light absorption. The PL spectra showed that the nitrogen defects promoted the separation of photogenerated electron–hole pairs. In the visible light degradation of methyl orange (MO), the reaction rate constant of 0.1[Formula: see text]M-LS-g-C3N4 reached 0.0086[Formula: see text][Formula: see text], which was 5.05 times that of pure g-C3N4. Superoxide radicals and photogenerated holes were found to be the main active species in the reaction system. This study provides an efficient, green and convenient means of preparing graphitic carbon nitride with a large specific surface area.

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Sugarcane juice derived carbon dot–graphitic carbon nitride composites for bisphenol A degradation under sunlight irradiation

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.9.35 ◽

2018 ◽

Vol 9 ◽

pp. 353-363 ◽

Cited By ~ 22

Author(s):

Lan Ching Sim ◽

Jing Lin Wong ◽

Chen Hong Hak ◽

Jun Yan Tai ◽

Kah Hon Leong ◽

...

Keyword(s):

Photocatalytic Activity ◽

Bisphenol A ◽

Carbon Nitride ◽

Separation Efficiency ◽

Sugarcane Juice ◽

Graphitic Carbon ◽

Graphitic Carbon Nitride ◽

Dominant Factor ◽

Spectroscopic Techniques ◽

X Ray

Carbon dots (CDs) and graphitic carbon nitride (g-C3N4) composites (CD/g-C3N4) were successfully synthesized by a hydrothermal method using urea and sugarcane juice as starting materials. The chemical composition, morphological structure and optical properties of the composites and CDs were characterized using various spectroscopic techniques as well as transmission electron microscopy. X-ray photoelectron spectroscopy (XPS) results revealed new signals for carbonyl and carboxyl groups originating from the CDs in CD/g-C3N4 composites while X-ray diffraction (XRD) results showed distortion of the host matrix after incorporating CDs into g-C3N4. Both analyses signified the interaction between g-C3N4 and CDs. The photoluminescence (PL) analysis indicated that the presence of too many CDs will create trap states at the CD/g-C3N4 interface, decelerating the electron (e−) transport. However, the CD/g-C3N4(0.5) composite with the highest coverage of CDs still achieved the best bisphenol A (BPA) degradation rate at 3.87 times higher than that of g-C3N4. Hence, the charge separation efficiency should not be one of the main factors responsible for the enhancement of the photocatalytic activity of CD/g-C3N4. Instead, the light absorption capability was the dominant factor since the photoreactivity correlated well with the ultraviolet–visible diffuse reflectance spectra (UV–vis DRS) results. Although the CDs did not display upconversion photoluminescence (UCPL) properties, the π-conjugated CDs served as a photosensitizer (like organic dyes) to sensitize g-C3N4 and injected electrons to the conduction band (CB) of g-C3N4, resulting in the extended absorption spectrum from the visible to the near-infrared (NIR) region. This extended spectral absorption allows for the generation of more electrons for the enhancement of BPA degradation. It was determined that the reactive radical species responsible for the photocatalytic activity were the superoxide anion radical (O2 •−) and holes (h+) after performing multiple scavenging tests.

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Isotype heterostructure of bulk and nanosheets of graphitic carbon nitride for efficient visible light photodegradation of methylene blue

RSC Advances ◽

10.1039/c6ra00933f ◽

2016 ◽

Vol 6 (30) ◽

pp. 24976-24984 ◽

Cited By ~ 38

Author(s):

Biswajit Choudhury ◽

P. K. Giri

Keyword(s):

Methylene Blue ◽

Charge Carrier ◽

Visible Light ◽

Band Gap ◽

Carbon Nitride ◽

Graphitic Carbon ◽

Graphitic Carbon Nitride ◽

Visible Light Photocatalysis ◽

Mean Lifetime

Isotype heterostructure of bulk and nanosheets of graphitic carbon nitride with effective band gap of 2.62 eV and charge carrier mean lifetime of 21 ns exhibits an efficient visible light photocatalysis.

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