Fenton-like photocatalytic oxidation and adsorption performance of MXene/g-C3N4 heterostructures under H2O2 oxidizer: experimental & modeling approach
Year: 2025
Type: article
Abstract: The rapid growth of textile industry has negatively impacted the health and quality of clean water sources, leading to an increase in water pollution disaster. To address these significant water effluent issues, there is a strong need for improved and effective environmental remediation processes to treat effluents containing organic contaminants. The present research explores the photocatalytic and adsorption capabilities of MXene/g-C 3 N 4 for the discoloration of methylene blue (MB) by introducing a strong oxidizing agent, such as hydrogen peroxide (H 2 O 2 ). To the best of our knowledge, this study is the first one to demonstrate that the MXene/g-C 3 N 4 photocatalyst could efficiently activate H 2 O 2 , reducing the MB concentration by up to 99.71% and 81.88% in 240 min via photocatalysis and adsorption processes, respectively. The addition of H 2 O 2 oxidant in photocatalysis system rapidly reduced the recombination rate of photogenerated electrons-hole pairs by producing powerful hydroxyl and superoxide radicals in the Fenton-like oxidation process. Langmuir–Hinshelwood kinetic modeling excellently described the degradation of MB, showing the highest R 2 value of up to 0.9896. The thermodynamic parameters, including Gibbs free energy (ΔG° = − 28.203 to − 30.095 kJ/mol), entropy (ΔS° = 94.558 kJ/mol K, enthalpy (ΔH° = 25.255 kJ/mol and activation energy (E a = 11.066 kJ/mol), confirmed that the system is spontaneous and favorable for MB degradation. The reduction in ΔG° contributed to the expansion of photocatalyst’s pores, while the positive value ΔS° at higher temperatures indicated an increase in the kinetic energy of the degradation system, encouraging a higher rate of diffusion of methylene blue towards MXene/g-C 3 N 4 . In adsorption modeling, the adsorption of MB followed intraparticle diffusion kinetics and Temkin isotherms, with the highest R 2 values of 0.9906 & 0.9965, respectively. A series of MXene/g-C 3 N 4 heterostructure photocatalysts (1, 4, 8 and 12 wt. %) was synthesized via a wet impregnation method and characterized through TEM and FESEM characterizations. This work provides new insights into the application of MXene/g-C 3 N 4 for the improvement of photocatalysis system by introducing a powerful oxidizer.
Source: Discover Catalysis.
Language: English
Field: Energy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $1,290
Award: G2753966178
OpenAlex ID: W4407448249