Doping of Graphitic Carbon Nitride with Non-Metal Elements and Its Applications in Photocatalysis
Abstract
:1. Introduction
2. Oxygen-Doped g-C3N4
3. Nitrogen-Doped g-C3N4
Precursor | Synthetic Method | C/N Atomic Ratio, Doped (Pristine) | Photocatalytic Process | Conditions of the Process | Efficiency Doped/Pristine | References |
---|---|---|---|---|---|---|
Melamine, N-N dimethylformamide (DMF) | Hydrothermal treatment | 0.407 (0.540) by EDS, 0.457 (0.575) by Organic Elemental Analysis (OEA) | H2 evolution | 300W Xe lamp, filter λ > 400 nm), co-catalysts Pt nanoparticles, triethanolamine (TEOA) as a hole quencher | 128.5 h−1/ 58.6 h−1, | [57] |
Melamine, hydrazine hydrate | Thermal condensation | 0.67 (0.73) by elemental analysis | H2 evolution | 300W Xe lamp, filter λ > 400 nm, TEOA (10 vol.%, Pt co-catalyst (3 wt.%) | 44.28 μmol·h−1/ 7.86 μmol⋅h−1 | [49] |
dicyandiamide | Secondary calcination | 57.57 (56.88) at.% by EDS | methylene blue degradation | 300W Xe lamp, filter λ > 420 nm | 0.02355 min−1/ 0.00829 min−1 | [50] |
Dicyandiamide, DMF | Thermal copolymerization | 0.67 (0.76) by XPS | Tetracycline (TC) degradation | 300W Xe lamp, filter λ > 420 nm | 76.78 (52.21)% of TC was degraded in 60 min | [52] |
Urea, DMF | Thermal copolymerization | 0.74 (0.59) at.% by organic elemental analysis | H2 evolution | 300W Xe lamp, filter λ > 400 nm, TEOA (10 vol.%), Pt co-catalyst (3 wt.%) | 5268 μmol g−1·h−1/ 3579 μmol g−1·h−1/ | [51] |
Urea, monoethanolamine | Amine functionalization of g-C3N4 | — | CO2 reduction | 300W Xe lamp, gas phase reaction | CH4: 0.34 μmol·h−1·g−1/trace; CH3OH: 0.26 μmol·h−1·g−1/ 0.26 μmol·h−1·g−1 | [58] |
Melamine, NH4Cl | Thermal polymerization | N content (at.%) doped 47.32 doped; 45.59 pristine | RhB degradation | 300W Xe lamp, 420 nm cutoff filter, | 0.01954 min−1/ 0.00391 min−1 | [59] |
Melamine, NH4Cl | Second-calcination approach | 1.14 (1.63) by XPS analysis | H2 evolution | 420-nm LED, lactic acid (10 vol%) solution, (Pt co-catalyst (1 wt%) | 15.5 mmol·h−1/ 7.5 mmol·h−1 | [65] |
Melamine, NH4Cl | Precursor formation by hydrothermal method; thermal polymerization in NH3, N2, Ar, air | 0.55-0.59 (0.69) by elemental analysis | CO2 reduction | 300 W Xe-lamp, CoCl2, 2,2-bipyridine, TEOA and methyl cyanide | 103.6 μmol·g−1·h−1/ 6.1 μmol·g−1·h−1 | [62] |
Citric acid, urea | Thermal polymerization | without change | H2 evolution | 300W Xe lamp, 420 nm cutoff filter, Pt nanoparticles (3 wt.%), triethanolamine as a hole quencher | 64 μmol·h−1/15 μmol·h−1 | [63] |
Dicyandiamide, citric acid, urea | Thermal polymerization | — | Indomethacine degradation | 350 W xenon lamp with 420 nm cutoff filter; 500 W mercury lamp; 350 W xenon lamp with a 290 nm cut-off filter | Photocatalytic activity was 1.1 (UV light irradiation), 1.8 (simulated sunlight), and 13.6 (visible light irradiation) times higher than that of pristine g-C3N4 | [66] |
Melamine, urea | Hydrothermal treatment | C:N mass ratio doped 0.53/0.73 by OEA; C:N atomic ratio 0.47/0.72 by quantitative XPS | H2 evolution | 300W Xe lamp, 420 nm cutoff filter, Pt nanoparticles (1 wt.%), 20% vol. lactic acid | 3579 μmol·h−1·g−1/ 147 μmol·h−1·g−1 | [64] |
Urea, N2 | Thermal polymerization | doped 0.71/0.73 by XPS | Bisphenol A oxidation; Cr(VI) reduction | 300W Xe lamp, 420 nm cutoff filter | Complete degradation of BPA 60 min/90 min; Photoreduction of Cr(VI) over 120 min: 10%/60% | [34] |
4. Carbon-Doped g-C3N4
5. Sulfur-Doped g-C3N4
6. P-Doped g-C3N4
Precursor | Synthetic Method | C/Doping Element Atomic Ratio, Doped (Pristine) | Photocatalytic Process | Conditions of the Process | Efficiency Doped/Pristine | References |
---|---|---|---|---|---|---|
g-C3N4, P powder | Thermal modification | P 2p signal at around 133.7 eV | H2 evolution | 300 W Xe lamp (λ > 300 nm), filter λ > 420 nm, 10% vol% TEOA, Pt co-catalyst (3 wt.%) | λ > 300 nm 261.2 µmol·g−1·h−1/81.6 µmol·g−1·h−1 λ > 420 nm 171.6 µmol·g−1·h−1/81.6 µmol·g−1·h−1 | [109] |
Urea, phosphonitrilic chloride | Thermal condensation | 4.4 atomic% by EDS 5.72 atomic% by XPS | H2O2 generation | Visible light irradiation (420 nm ≤ λ ≤ 700 nm) | 1968 μmol·g−1·h−1/ 68 μmol·g−1·h−1 | [108] |
NH4SCN, NH4PF6 | Thermal condensation | — | RhB destruction | 300 W Xe lamp, filter λ > 420 nm | 0.09856 min−1/ 0.03679 min−1 | [110] |
g-C3N4, phosphorene | Mechanically mixing | 1.8 wt.% | H2 evolution | 300 W Xe lamp, filter λ > 400 nm, lactic acid (88 vol%) | 571 µmol·g−1·h−1/ 43 μmol·g−1·h−1 | [117] |
g-C3N4, sodium hypophosphite | Thermal treatment method | 13.52 wt.% | RhB destruction | 300 W Xe lamp, λ: 420–780 nm, | 0.0525 min−1/ 0.0126min−1 | [115] |
Urea, adenosine phosphate | Thermal condensation followed by thermal exfoliation method | 2.17 atomic% | H2 evolution | 300 W Xe lamp, filters λ: 400, 420, 435, 450, 550 nm; 10% vol% TEOA, Pt co-catalyst (3 wt.%) | 9523.7 µmol·g−1·h−1/ 458 μmol·g−1·h−1 | [118] |
Urea, NH4H2PO2 | Thermal condensation | — | H2 evolution | 300 W Xe lamp, filter λ 400 nm, 20% vol% TEOA, Pt co-catalyst (1 wt.%) | 5.7 times that of pristine | [119] |
Dicyandiamide, NH4Cl, (NH4)2HPO4 | Thermal condensation | 1.53 wt% by EDS | H2 evolution | 300 W Xe lamp, filter λ 420 nm, 10% vol% TEOA, Pt co-catalyst (3 wt.%) | 33.2 µmol·g−1·h−1/ 10.7 μmol·g−1·h−1 | [126] |
7. Vacancy-Doped g-C3N4
8. Photocatalytic Applications of Non-Metal Elements Doped g-C3N4
8.1. Photocatalytic CO2 Reduction
8.2. H2-Evolution
8.3. Degradation of Dyes and Organic Pollutants
9. Conclusions
Author Contributions
Funding
Conflicts of Interest
References
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Precursor | Synthetic Method | C/O Ratio, Doped (Pristine) | Photocatalytic Process | Conditions of the Process | Efficiency Doped/Pristine | References |
---|---|---|---|---|---|---|
Urea | H2O2 hydrothermal treatment, 120 °C | Surface O at.% in O-doped g-C3N4 3.23–6.59 by XPS | H2 evolution | 500 W Xe lamp, simulate solar irradiation; 30 vol% triethanolamine (TEOA) | 408.4 μmol·g−1/ 317.9 μmol·g−1 | [24] |
Melamine | PMS hydrothermal treatment, 60 °C | 3.16%/2.73% by Energy-Dispersive X-Ray Spectroscopy (EDS) 1.8%/2.8% by XPS | Rhodamine B (RhB) destruction | 500 W halogen lamp, filter λ > 420 nm | 0.079 min−1/0.0032 min−1 | [17] |
Urea | H2O2 hydrothermal treatment, 120 °C | — | RhB, Methyl orange (MO) destruction | 500 W Xe lamp, simulated solar irradiation | RhB:0.1074 h−1/0.0170 h−1 MO: 0.2287 h−1/0.0095 h−1 | [41] |
Urea, ammonium acetate | two-step thermal treatment | 4.3/8.8 by elemental analysis (EA) | bisphenol A (BPA), phenol (Ph), 2-chlorphenol (2-Ph), diphenhydramine destruction (DP) | Light-emitting diode (LED) lamp, λ = 420–780 nm | Total organic carbon (TOC) removal rate: BPA 72.79%/9.27%; Ph 67.3%, 2-Ph 61.5%, DP 55.0% | [19] |
Melamine, ethanol | Thermal polymerization | Atom.% (O) 3.25/- by XPS | H2 evolution | 350 W Xe lamp, filter λ > 420 nm, 10% vol% TEOA, Pt co-catalyst (1 wt.%) | 64.30 μmol·h−1/ 3.6 μmol·h−1 | [42] |
1,3,5-Trichloro-triazine, dicyandiami-de | Solvothermal method, 200 °C | C:N:O 1.08:1:0.23/ 0.69:1:0.03 by XPS | H2 evolution; RhB destruction | Visible light, λ > 420, Pt co-catalyst (0.3 wt.%) | H2 evolution: 3174 μmol·h−1 g −1/846 μmol·h−1·g −1 RhB degradation: 0.249 min−1/0.007min−1 | [22] |
Melamine | Thermal polycondensation | 12.5/trace by XPS | CO2 reduction | 350 W Xe lamp, filter λ > 420 nm | CH3OH production 0.88 µmol·g−1·h−1/ 0.17 µmol·g−1·h−1 | [43] |
Dicyandia-midine | Hydrothermal followed by calcination | O content (wt.%) 5.23/0.17 by EA | N2 fixation | 500 W Xenon lamp filter λ > 420 nm, 10 vol.% methanol as sacrificial agents | 118.8 mg·l−1·h−1·gcat−1/ 5.86 mg·l−1·h−1·gcat−1 | [18] |
Precursor | Synthetic Method | C/N Doped (Pristine) | Photocatalytic Process | Conditions of the Process | Efficiency Doped/Pristine | References |
---|---|---|---|---|---|---|
Dicyanamide, dimethylformamide | Thermal copolymerization | C/N mass ratio 0.61(0.59) by elemental analysis | H2 evolution | 300W Xe lamp, filter λ > 400 nm), Pt co-catalyst (1 wt.%), triethanolamine (TEOA) as a hole quencher | 35.5 μmol/ 6.78 μmol in 8 h | [71] |
Melamine, cellulose | thermal treatment | C/N mass ratio 33.39 (30.12) by elemental analysis | H2 evolution | 300W Xe lamp, filter λ > 420 nm), Pt (3%), TEOA (10 vol%) | 1024 μmol·g−1·h−1/ 59.6 μmol·g−1·h−1 | [68] |
Melamine, Urea, phenylmalonic acid | Precursor copolymerization on the surface of g-C3N4 | C/N at. Ratio 68.9 (43.0) C, % 33.52 (33.45) by elemental analysis | bisphenol A (BPA) destruction H2 evolution | 300W Xe lamp, filter λ > 420 nm, Pt (3%), TEOA (10 vol%) | BPA destruction: 0.0507 min−1/0.0038 min−1; H2 evolution: 31 μmol·h−1/10 μmol·h−1 | [73] |
Cyanuric acid, ethylene glycol, melamine | microwave treatment of supramolecular aggregates | C/N at. Ratio 0.688 (0.669) C, %: 39.98 (39.51) by elemental analysis | N2 photofixation | 250W high-pressure Na lamp (400 < l < 800 nm) | 5.3 mg·L−1·gcat−1/ 0.48 mg·L−1·gcat−1 | [88] |
Urea, C60 nanorods | liquid-liquid interfacial precipitation method | - | H2 evolution | 500 W Xe lamp, filter λ > 420 nm, Pt (3%), TEOA (17 vol%) | 8.7 μmol·h−1/ 1.85 μmol·h−1 | [76] |
Agar-melamine gel | one-step thermal condensation method | C/N at. Ratio 0.69 (0.67) C, %: 34.9 (35.33) by elemental analysis C/N at. Ratio 0.90 (0.87) by XPS | RhB, Phenol, BPA, Phe destruction | 300 W Xe lamp, filter λ > 420 nm | RhB destruction 0.042 min−1/ 0.016 min−1 BPA destruction 0.145 min−1/ 0.113min−1 | [79] |
Urea, sacharose | Thermal polymerization | C/N at. Ratio 0.58 (0.57) C, %: 34.83 (34.81) by XPS analysis | NO removal | Xe lamp, filter λ > 420 nm | NO removal ratio 56.77%/ 50.89% | [82] |
Melamine, carbon dots (CD) | combining g-C3N4 treated with H2O2 and CD | C wt.%: 46.77(39.78) by EDX | MB, RhB, fuchsine, Phe destruction; Cr(VI) photoreduction | 50 W LED lamp, visible light irradiation | RhB destruction 0.0675 min−1/ 0.0019 min−1 | [67] |
Precursor | Synthetic Method | Content of Sulfur | Photocatalytic Process | Conditions of the Process | Efficiency Doped/Pristine | References |
---|---|---|---|---|---|---|
Melamine, sulfur | Thermal polycondensation, 520 °C | - | O2 evolution; scheme H2O splitting; bactericidal activity | 400 W halide lamp (λmax = 360 nm), 150 W Xe lamp, filter λ > 400 nm [Co(bpy)3]SO4 as electron mediator, Ru/SrTiO3:Rh as cocatalyst | O2 evolution: 40.3 μmol·h−1/- Z-scheme H2O splitting: 29.3 μmol·h−1/-; 70% of bacteria were killed | [96] |
Melamine, (NH4)2SO4 | Upgraded gas templating method | — | H2 evolution | 350 W Xe lamp, filter λ > 420 nm, 10% vol% TEOA, Pt co-catalyst (1 wt.%) | 572 μmol·h−1·g−1/ 78 μmol·h−1·g−1 | [106] |
Urea, thioacetamide | One-pot copolymerization | 0.1 at.% S 0.2 by XPS | Procion Red MX-5B degradation H2 evolution | 500 W Xe lamp, monochromic light provided by using a 420 ± 15, 450 ± 15, 475 ± 15 and 520 ± 15 nm band pass filter TEOA, Pt co-catalyst (1 wt.%) | Dye degradation 0.072 min−1/0.024 min−1 H2 evolution 3.17 mmol·g−1·h−1/ 0.84 mmol·g−1·h−1 | [103] |
Thiourea | Thermal polycondensation followed by thermal oxidative etching | S content: 0.45 by OEA, 1.58 by XPS | Phenol degradation; H2 evolution | 300 W Xe lamp, 5% vol% TEOA, Pt co-catalyst (1 wt.%) | 75%/100% of Phenol was decomposed; H2 evolution: 127.4 μmol·h−1/ 0.5 μmol·h−1 | [90] |
Thiourea, mesyl chloride | Post-synthetic derivatization of g-C3N4 | - | Acid Orange 7 dye degradation | UVA tube lamp, λmax = 368 nm | 0.113 min−1/0.022 min−1 | [99] |
1,3,5-trichlorotriazine, Melamine, Trithiocyanuric acid | Solvothermal condensation process, 180 °C | - | Cr(VI) reduction | Irradiation with λ > 420 nm | 1.85 min−1/0.03 min−1 | [104] |
Melamine, Trithiocyanuric acid | Thermal polycondensation of the supramolecular complex | S (wt%): 0.63 | RhB degradation | 500 W Xe lamp, filter λ > 420 nm | 0.0167 min−1/0.0013 min−1 | [95] |
Urea, benzyl disulfide | Thermal polycondensation, 520 °C | - | Reduction elimination of UO22+ | 350 W Xe lamp, λ ≥ 420 nm | 0.16 min−1/0.07 min−1 | [101] |
Urea, thiourea | Thermal polycondensation, 550 °C | - | H2 evolution | 300 W Xe lamp, filter λ > 420 nm, 10% vol% TEOA | 95.3 μmol·h−1/ 36.4 μmol·h−1 | [100] |
Melamine, sulfuric acid | Sulfuring and sonicating bulk g-C3N4 | - | 4-nitrophenol degradation | 500 W Xe lamp, filter λ > 400 nm | 3.47 × 10−2 min−1/ 7.04 × 10−4 min−1 | [107] |
Thiourea | Thermal polycondensation, 520 °C | S atomic% 0.05 by EA | CO2 reduction | 300 W Xe lamp, Pt co-catalyst (1 wt.%) | CH3OH formation: 1.12 μmol·g−1/0.81 μmol·g−1 | [98] |
Precursor | Synthetic Method | C/N Element Atomic Ratio, Doped (Pristine) | Photocatalytic Process | Conditions of the Process | Efficiency Doped/Pristine | References |
---|---|---|---|---|---|---|
Urea, oxalyl dihydrazide (ODH) | Thermal copolymerization | 0.74 (0.65) by element analysis; 0.67 (0.61) by XPS 1.87 (1.09) by EDX | Tetracycline hydrochloride (TC-HCl) and sulfamethoxazole (SMZ) destruction; H2 evolution | 300 W Xe lamp, filter λ > 420 nm, Pt co-catalyst (1wt.%), TEOA | SMZ destruction: 0.0203min−1/ 0.0066 min−1; H2 evolution: 5833.1 μmol·h−1·g−1/ 1458.2 μmol·g−1 | [133] |
Urea, dicyandiamide | Post-thermal treatment of g-C3N4 | — | H2 evolution | Visible light irradiation | 6.5 μmol·g−1/ 2.1 μmol·g−1 | [137] |
Melamine | Polymerization in atmosphere of: CCl4; H2; Ar | 0.61 (0.65) by elemental analysis | H2 evolution | 300W Xe lamp, filter λ > 420 nm), Pt (3%), TEOA (10 vol%) | 0.079 min−1/ 0.0032 min−1 | [128] |
Urea | KOH-assisted calcination treatment | 1.45 (1.51) by organic elemental analysis 1.32 (1.64) by XPS | H2O2 production | simulated sunlight lamp 20 vol% ethanol | 152.6 μmol·h−1/ 10.2 μmol·h−1 | [131] |
Dicyandiamide, NH4Cl, 3-amino-1,2,4-triazol | Thermal polymerization with post treatment in N2 | 1.260 (1.489) by element analysis | H2 evolution | 300W Xe lamp, filter λ > 400 nm), Pt (3%), TEOA (10 vol%) | 3882.5 μmol·h−1·g−1/ 85.0 μmol·h−1·g−1 | [134] |
Urea, Mg powder | magnesium vapor etching | 0.51 (0.78) by EDX 0.92 (1.14) by XPS | H2 evolution | 300W Xe lamp, filter λ > 400 nm), Pt (3%), TEOA (10 vol%) | 450 μmol·h−1·g−1/ 225 μmol·h−1·g−1 | [88] |
Dicyandiamide | two-step calcination | 0.81 (0.85) by XPS | N2 fixation | 300W Xe lamp | NH4+ formation: 54 mmol·L−1/ 24 mmol·L−1 | [139] |
Urea, melamine | precursor preprocessing and thermolysis in N2 | — | NO oxidation | LED lamp (λ ≥ 448 nm) | the NO oxidation in 30 min of irradiation 47.7%/22% | [140] |
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Starukh, H.; Praus, P. Doping of Graphitic Carbon Nitride with Non-Metal Elements and Its Applications in Photocatalysis. Catalysts 2020, 10, 1119. https://0-doi-org.brum.beds.ac.uk/10.3390/catal10101119
Starukh H, Praus P. Doping of Graphitic Carbon Nitride with Non-Metal Elements and Its Applications in Photocatalysis. Catalysts. 2020; 10(10):1119. https://0-doi-org.brum.beds.ac.uk/10.3390/catal10101119
Chicago/Turabian StyleStarukh, Halyna, and Petr Praus. 2020. "Doping of Graphitic Carbon Nitride with Non-Metal Elements and Its Applications in Photocatalysis" Catalysts 10, no. 10: 1119. https://0-doi-org.brum.beds.ac.uk/10.3390/catal10101119