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Fluorinated graphitic carbon nitride has demonstrated promising and interesting photocatalytic properties and more particularly for degradation of organic pollutants. In this study, graphitic carbon nitride (g-C 3 N 4 ) was fluorinated using a F 2 /N 2 mixture under controlled conditions and high amount of fluorine atoms are obtained (as about ~19 at.%). Electron paramagnetic resonance (EPR) analysis reveals that fluorination significantly enhances charge generation upon light exposure, leading to the production of highly reactive species (e.g., OH • ) that can help for the efficient degradation of organic pollutants. The photocatalytic performance and mechanism of fluorinated g-C 3 N 4 (g-C 3 N 4 -F) was evaluated through the degradation of methyl orange (MO) and carbamazepine (CBZ) used as model organic pollutants. The role of the inserted fluorine atoms, the acidity, the structural modifications on the photocatalytic mechanisms of g-C 3 N 4 were explored. Fluorinated g-C 3 N 4 greatly increases the acidity, from pH = 6.1 to 3.1, of the contaminated solution inducing changes in the adsorption. The degradation of MO increases from 19.9% to 92.8% after 2 h under light irradiation with pristine g-C 3 N 4 and fluorinated g-C 3 N 4 respectively. Scavenger tests confirm that OH • and holes are the main active species for MO degradation. Additionally, CBZ degradation leads to various by-products distribution depending on whether g-C 3 N 4 is fluorinated or not induced by different degradation pathways. Finally, the reversible fluorination of g-C 3 N 4 was successfully demonstrated, highlighting the potential for material recycling. The defluorinated evidence similar photocatalytic performances as pristine g-C 3 N 4 , highlighting the important effect of the fluorination to improve the photocatalytic activity of g-C 3 N 4 . • New fluorination method of g-C 3 N 4 with F 2 fluorination at T amb allowing the highest amount of fluorine atoms, 19 at.%, at the surface of the material. • New defluorination technic of fluorinated g-C 3 N 4 with a strong reducer. • Mechanisms of degradation, at high degradation efficiency, of methyl orange by pristine, fluorinated and defluorinated g-C 3 N 4 identified. • Different distribution of degradation products of carbamazepine according to the catalyst used.