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Table 17.1. Earlier reported works on g-C3N4-based photocatalytic water splitting.
Photocatalyst
Light Source
Photocatalysis Rate
References
TiO2-g-C3N4
Xenon lamp (320nm)
76.25 µmol·h−1
Qu et al. 2016
TiO2 nanodots/g-C3N4
Xenon lamp (300W)
H2 evolution rate=1318.3 µmol g−1
O2 evolution rate=638.7 µmol g−1
Jiang et al. 2022
N-doped ZnO-g-C3N4
PLS-SXE-300C UV lamp
152.7 µmol·h−1
Liu et al. 2019
S-Cu2O/g-C3N4
Xenon lamp (300W)
24.83 µmol·h−1
Gu et al. 2021
BiO2/g-C3N4
Xenon lamp (500nm)
8,542 µmol·g−1
Alhaddad et al. 2020
Mn3O4/g-C3N4
Xenon lamp (300W)
2700 mmol g–1 h–1
Li et al. 2021
g-C3N4/Nitrogen-Doped
Carbon Dots/WO3
Xenon lamp (300W)
3.27 mmol g–1 h–1
Song et al. 2021
MoO3-x-g-C3N4
Xenon lamp (300W)
22.8 mmol h−1
Guo et al. 2020
TiO2/Ti3C2/g-C3N4
Xenon lamp (300W)
2592 mmol·g−1
Hieu et al. 2021
ZnO/Au/g-C3N4
Xenon lamp (150W)
3.69 µmol h−1 cm−2
Wen et al. 2020
Table 17.2. A list of CO2 reduction applications of the metal oxide-based g-C3N4 photocatalysts.
Photocatalyst
Light Source
Photocatalysis Rate
References
NiO-g-C3N4
Xenon lamp (300 W)
4.17
Tang et al. 2018
g-C3N4 foam-Cu2O
350 W Lamp
8.182
Sun et al. 2019
ZnO/Au/g-C3N4
UV-Vi’s lamp (300W)
689.7 µmol/m2 (CO evolution)
Li et al. 2021
TiO2/g-C3N4
UV-Vi’s lamp (8W)
CH4 and CO yields of 72.2 and
56.2 µmol g–1
Wang et al. 2020
ZnO/g-C3N4
Xenon lamp (300 W)
The CH3OH production rate was
1.32 µmol h–1 g–1
Nie et al. 2018
g-C3N4/3D ordered
microporous (3DOM)-WO3
visible light
48.7 µmol h–1 g–1
Tang et al. 2022
NiTO3/g-C3N4
Xenon lamp
(300 W)
CH3OH production is
13.74 molg–1 h–1
Guo et al. 2021
17.5.1.3 Photodegradation of Organic Pollutants
Several environmental issues are brought on by the growth of an increasing number of dye-related
businesses, including textile, food and furniture manufacturers. Additionally, having an unfavorable
visual effect on water sources, organic dyes also cause wastewater to have a higher COD. Diverse
techniques such as adsorption, membrane separation and coagulation have been explored to remove
organic pollutants from effluents, but these only move organic dyes from the liquid phase of
wastewater to the solid phase. This creates secondary pollution in the environment. Most metal
oxides may degrade and transform organic colors into particles during photocatalysis, which uses
solar energy to start the reaction. The most stable dyes in water at room temperature are Rhodamine
B (RhB), Methylene Orange (MO) and Methylene Blue (MB) (Si et al. 2020). Since MB and RhB
are toxic dyes, the health of people and aquatic animals may be negatively impacted by their high
concentration. Wastewater treatment is a pressing issue because of the high resistivity of the RhB
and MB under various environmental conditions.
Therefore, providing a reliable and affordable technique to remove MB and RhB from sewage is
imperative. According to reports, the optimal composition for g-C3N4-ZnO nanocomposites is 30%
weight, which results in the maximum MB degradation efficiency (Liu et al. 2018). The more g-C3N4,
the more likely it is that electrons and holes will recombine, decreasing the photocatalytic activity.
Additionally, it should be noted that this composite’s RhB degrading efficiency is approximately
2.1 times greater than that of pure ZnO (Chen et al. 2018). g-C3N4-TiO2 heterojunction, in addition