3N4 Composite Catalyst Research Articles

Boosted photocatalytic performance of cobalt ferrite anchored g-C3N4 nanocomposite toward various emerging environmental hazardous pollutants degradation: insights into stability and Z-scheme mechanism.

In this study, a highly efficient CoFe2O4-anchored g-C3N4 nanocomposite with Z-scheme photocatalyst was developed by facile calcination and hydrothermal technique. To evaluate the crystalline structure, sample surface morphology, elemental compositions, and charge conductivity of the as-synthesized catalysts by various characterization techniques. The high interfacial contact of CoFe2O4 nanoparticles (NPs) with g-C3N4 nanosheets reduced the optical bandgap from 2.67 to 2.5eV, which improved the charge carrier separation and transfer. The photo-degradation of methylene blue (MB) and rhodamine B (Rh B) aqueous pollutant suspension under visible-light influence was used to investigate the photocatalytic degradation activity of the efficient CoFe2O4/g-C3N4 composite catalyst. The heterostructured spinel CoFe2O4 anchored g-C3N4 photocatalysts (PCs) with Z-scheme show better photocatalytic degradation performance for both organic dyes. Meanwhile, the efficiency of aqueous MB and Rh B degradation in 120 and 100min under visible-light could be up to 91.1% and 73.7%, which is greater than pristine g-C3N4 and CoFe2O4 catalysts. The recycling stability test showed no significant changes in the photo-degradation activity after four repeated cycles. Thus, this work provides an efficient tactic for the construction of highly efficient magnetic PCs for the removal of hazardous pollutants in the aquatic environment.

G-C3N4 nanosheet supported NiCo2O4 nanoparticles for boosting degradation of tetracycline under visible light and ultrasonic irradiation.

The doping of semiconductor materials through some facile and appropriate methods holds significant promise in enhancing the catalytic performance of catalysts. Herein, NiCo2O4/g-C3N4 composite catalysts were synthesized via a high-energy ball milling method. The microstructure and physicochemical characterization of the as-prepared composites confirmed the successful loading of NiCo2O4 nanoparticles onto the g-C3N4 nanosheets. The NiCo2O4/g-C3N4 composites showed excellent catalytic effect under visible light/ultrasonic irradiation, and the efficiency of tetracycline hydrochloride (TCH) degradation reached 90% within 15 min. The optical properties of g-C3N4 nanosheets were improved by doping, and the diffusion of active materials and carrier migration rate were improved by ultrasonic assistance. Possible catalytic mechanisms and potential pathways of the NiCo2O4/g-C3N4 composites for the degradation of TCH triggered by visible light/ultrasonic irradiation were proposed. This study provides a new strategy for energy-assisted photocatalytic degradation of organic pollutants.

Exploiting synergistic effects: Co3O4/g-C3N4 composite catalyst for enhanced oxygen evolution reaction

In this study, we explore the potential of Co3O4/g-C3N4 composite catalysts for improving the oxygen evolution reaction (OER) performance. By employing a rotating disk electrode in 0.1 mol L−1 KOH electrolyte, we systematically investigate the OER properties of various ratios of Co3O4/g-C3N4 catalysts. Our findings reveal that Co3O4/g-C3N4-0.2 catalyst outperforms pure g-C3N4, exhibiting significantly higher current density (10 mA cm−2) and lower overpotential (627 mV). Furthermore, Tafel slope analysis demonstrates enhanced reaction kinetics, with Co3O4/g-C3N4-0.2 catalyst displaying the smallest Tafel slope (54 mV dec−1). Electrochemical impedance spectroscopy (EIS) confirms the superior charge transfer efficiency of Co3O4/g-C3N4-0.2 catalyst compared to other ratios and pure g-C3N4. Impressively, stability tests demonstrate only 5.4% performance decay after 1000 CV cycles, highlighting the excellent stability of Co3O4/g-C3N4-0.2 catalyst. These findings underscore the remarkable potential of Co3O4/g-C3N4 composite catalysts in OER applications. The synergistic effects between Co3O4 and g-C3N4 contribute to enhanced electrocatalytic performance, making it a promising candidate for future OER advancements.

Z-Scheme ZnV2O4/g-C3N4 Heterojunction Catalyst Produced by the One-Pot Method for the Degradation of Tetracycline under Visible Light

A novel Z-scheme ZnV2O4/g-C3N4 composite catalyst was prepared using a one-pot calcination method, and the photodegradation performance of the ZnV2O4/g-C3N4 heterojunction was studied under simulated sunlight condition. Under visible-light treatment, the ZnV2O4/g-C3N4 catalyst showed excellent catalytic activity in the degradation of tetracycline (TC), and compared with pure g-C3N4 and ZnV2O4, its photocatalytic degradation efficiency was significantly improved. The performances of the ZnV2O4/g-C3N4 catalyst were compared under different ZnV2O4 loading rates, catalyst dosage, pollutant concentrations, and initial pH values of the solution. The experimental results showed that the 35 wt % ZnV2O4/g-C3N4 (35ZVO/CN) had the best photocatalytic activity. The appreciable improvement in performance was mainly due to the construction of the Z-scheme structure between ZnV2O4 and g-C3N4, which promoted the effective separation of charge carriers. In addition, a possible mechanism of the photodegradation process of 35ZVO/CN was discussed based on the energy band position analyses and active radical capture experiments. That superoxide radical was the main reaction specie confirmed the Z-scheme mechanism. By forming the Z-scheme heterojunction, the efficiency of charge separation and transfer was improved, and the catalyst had strong oxidation and reduction abilities. This research provided a new enlightenment for the construction and synthesis of a low-cost Z-scheme heterojunction photocatalyst and the treatment of antibiotics in water.

Effect of hydrogen bond interaction in precursor on photocatalytic oxidation of MB by C-GA/g-C3N4 composites

It is well known that the design of precursor structure is an effective method to optimize the photocatalytic activity of g-C3N4, and it will be interesting to investigate the relationship between the precursor structure and the structure of the target catalyst. In this paper, by adjusting the addition amount of glutaraldehyde (GA), three kinds of glutaraldehyde/dicyandiamide (GA/DCDA) precursors with equilibrium/imbalance hydrogen bond interaction can be obtained, and the carbonized glutaraldehyde (C-GA)/g-C3N4 composite catalysts with different carbon content can be obtained after calcination. The obtained C-GA/g-C3N4 composite catalysts have different photocatalytic activity for methylene blue degradation. Compared with the original g-C3N4, the photocatalytic activity of C-GA/g-C3N4-2 composite is increased by 2.69 times. Through the analysis of thermal decomposition kinetics and structural characterization, we can see that the equilibrium interaction in the structure of GA/DCDA-2 precursor can promote the conversion of dicyandiamide to melamine, and glutaraldehyde carbonization will form more C-GA, and form a composite catalyst with closer interaction with g-C3N4. C-GA with close interaction and higher content can effectively promote the separation of photogenerated carriers and visible light absorption, thus improving its photocatalytic activity.

WSe2/g-C3N4 for an In Situ Photocatalytic Fenton-like System in Phenol Degradation.

An in situ photo-Fenton system can continuously generate H2O2 by photocatalysis, activating H2O2 in situ to form strong oxidizing ·OH radicals and degrading organic pollutants. A WSe2/g-C3N4 composite catalyst with WSe2 as a co-catalyst was successfully synthesized in this work and used for in situ photo-Fenton oxidation. The WSe2/g-C3N4 composite with 7% loading of WSe2 (CNW2) has H2O2 production of 35.04 μmol/L, which is fourteen times higher than pure g-C3N4. The degradation efficiency of CNW2 for phenol reached 67%. By constructing an in situ Fenton-system, the phenol degradation rate could be further enhanced to 90%. WSe2 can enhance the catalytic activity of CNW2 by increasing electron mobility and inhibiting the recombination of photogenerated electron–hole pairs. Moreover, the addition of Fe2+ activates the generated H2O2, thus increasing the amount of strong oxidative ·OH radicals for the degradation of phenol. Overall, CNW2 is a promising novel material with a high H2O2 yield and can directly degrade organic pollutants using an in situ photo-Fenton reaction.

Influence of preparation methods in the structure and properties of Fe2O3/g-C3N4 composite catalysts

The control of performance-oriented materials structure will be limited by the preparation of materials, and the research on the correlation between the preparation methods and the target structure will be an interesting direction. In this paper, three kinds of precursor mixture of Fe2O3 and g-C3N4 (FeCl3/DCDA-1, 2, 3) were prepared by mechanical compounding and simple hydrothermal method respectively. After calcination under the same conditions, Fe2O3/g-C3N4 composite catalysts were prepared. The relationship between the structure of the precursor obtained by different preparation methods and the performance of the composite catalyst was studied by thermal decomposition kinetics. The results show that in the simple hydrothermal method, compared with FeCl3/DCDA-3 obtained by drying only the composite crystals precipitated in the mixed solution, the activation energy of FeCl3/DCDA-2 obtained by drying the mixed solution increases with the increase of conversion rate, and has a higher pre exponential factor A value. This may be due to the increasingly strong interaction between Fe(OH)3 and dicyandiamide in FeCl3/DCDA-2, which makes dicyandiamide difficult to be converted into melamine in the calcination process. As a result, the interface interaction between Fe2O3 and g-C3N4 in the composite catalyst becomes stronger, forming a strong Fe–N coordination bond and promoting the separation of electron holes. Fe2O3/g–C3N4–2 has the highest photocatalytic activity among the prepared photocatalysts. It can degrade 62.0% of methylene blue (MB) under visible light irradiation for 60 min, which is 2.32 times that of pure g-C3N4 (34.6%). In addition, under the same conditions, Fe2O3/g–C3N4–2 can degrade 7.72% of ciprofloxacin (CIP).

Polymeric iron phthalocyanine/g-C3N4 composite catalyst by mechanical force enhanced stripping and recombination for solar-induced contaminant degradation and CO2 reduction

Solar light response photocatalysts have been extensively studied to alleviate energy crisis and solve environmental pollution problems. Herein, polymerized iron phthalocyanine (FePPc) was prepared and then compounded with graphitic carbon nitride (g-C3N4) by ball milling to obtain FePPc/g-C3N4 composite photocatalyst. During the ball milling process, FePPc was mechanically exfoliated and compounded with g-C3N4, which the binding mode mainly relied on π-π stacking interaction with each other. Carbamazepine (CBZ) was completely removed within 15 min by FePPc/g-C3N4 under solar irradiation in the presence of peroxymonosulfate (PMS). Moreover, carbon dioxide (CO2) was also effectively reduced in the solar light responsive catalytic system with FePPc/g-C3N4 and the CO yield was 3388.98 µmol/g in 12 h. Compared with small molecule iron phthalocyanine (FePc)/g-C3N4, FePPc/g-C3N4 presented a significantly enhanced photocatalytic oxidation and reduction performance under solar light irradiation. Significantly, the visible light response of composite catalyst has been broadened due to FePPc sensitization, which reaching the near-IR light absorption band. Meanwhile, the compounding of photogenerated electron-hole pairs were efficaciously suppressed originating from the stronger bonding and greater electronic transfer between FePPc and g-C3N4. This work provides an effective basis for improving the utilization of sunlight in wastewater treatment and CO2 reduction.

WO3/BP/g-C3N4 –based cauliflower nanocomposite fabricated by pulsed laser ablation for overall water splitting

Fast recombination of photoinduced charge carriers due to poor charge separation are the fundamental challenges of particulate photocatalysis. One of the key solutions to mitigate these problems is the construction of heterojunction nanocomposites. In this study, we present a heterojunction composing of tungsten oxide/ black phosphorous and graphitic nitride (WO3/BP/g-C3N4) fabricated via pulsed laser ablation in liquid. To highlights the synergistic role of the fabricated components, the following photocatalysts were also prepared, WO3, WO3/BP, and g-C3N4. The overall photocatalytic production of hydrogen was examined for WO3, WO3/BP, g-C3N4, and WO3/BP/g-C3N4. There was no detectable production of hydrogen gas for the WO3 and g-C3N4. However, the hydrogen production rate was approximately 75 µmolg−1h−1 for the WO3/BP. The production rate substantially increased to 400 µmolg−1h−1 for the WO3/BP/g-C3N4 photocatalyst. The enhancement can be attributed to the cumulative increase in the UV–visible light absorption, mainly by BP and partially g-C3N4 in the fabricated WO3/BP/g-C3N4, as well as the effective charge transport leading to separation of charge carriers which is well explained using the Z-scheme mechanism. Moreover, the WO3/BP/g-C3N4 composite catalysts produced stable and consistent results after a prolonged operation which indicates the reusability of the photocatalyst.

MoS2 and Fe2O3 co-modify g-C3N4 to improve the performance of photocatalytic hydrogen production

Photocatalytic hydrogen production as a technology to solve energy and environmental problems exhibits great prospect and the exploration of new photocatalytic materials is crucial. In this research, the ternary composite catalyst of MoS2/Fe2O3/g-C3N4 was successfully prepared by a hydrothermal method, and then a series of characterizations were conducted. The characterization results demonstrated that the composite catalyst had better photocatalytic performance and experiment results had confirmed that the MoS2/Fe2O3/g-C3N4 composite catalyst had a higher hydrogen production rate than the single-component catalyst g-C3N4, which was 7.82 mmol g−1 h−1, about 5 times higher than the catalyst g-C3N4 (1.56 mmol g−1 h−1). The improvement of its photocatalytic activity can be mainly attributed to its enhanced absorption of visible light and the increase of the specific surface area, which provided more reactive sites for the composite catalyst. The successful preparation of composite catalyst provided more channels for carrier migration and reduced the recombination of photogenerated electrons and holes. Meanwhile, the composite catalyst also showed higher stability and repeatability.

Constructing a novel NaLa(WO4)2/g-C3N4 Z-scheme heterojunction with efficient carrier separation for excellent photocatalytic purification of NO

In this paper, a novel NaLa(WO4)2/g-C3N4 photocatalyst with Z-scheme heterojunction was synthesized for the first time, and the photocatalytic purification of NOx was used as an evaluation method of its activity. The structure was analyzed in depth by X-ray Diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and other characterization methods. NaLa(WO4)2 and g-C3N4 have obvious interfaces and successfully constructed a Z-scheme heterojunction structure. The combination of photogenerated electrons on the conduction band (CB) of NaLa(WO4)2 with holes on the valence band (VB) of g-C3N4 leads to the accumulation of the remaining holes and electrons on the VB of NaLa(WO4)2 and CB of g-C3N4, and finally realizes the effective separation of photogenerated carriers and maintains the high redox ability of the catalyst. The NaLa(WO4)2/g-C3N4 composite catalyst has a highest NO purification rate of 47.18%, which is 16.51% higher than pure g-C3N4. Moreover, the In-situ DRIFTS monitors the reaction intermediates and final products of NO on the NaLa(WO4)2/g-C3N4 heterojunction surface under visible light irradiation, and provides the corresponding reaction equations. This work provides a new type of photocatalyst that is easy to prepare and highly active, as well as a low-cost photocatalytic treatment technology to remove NO in the environment.

2-D Heterometallic Pb-Iodoargentate Framework [PbAg2I6]n with a Diskoid [Pb(18-crown-6)]2+ Linker and Cocatalyst for Synergistically Enhanced Photocatalytic Properties via g-C3N4 Doping.

The heterometallic Pb-iodoargentate hybrid [Pb(18-crown-6)(PbAg2I6)]n (1; 18-crown-6 = 1,4,7,10,13,16-hexaoxacyclooctadecane) was prepared via self-assembly of the tetrahedal AgI4 and octahedral PbI6 primary units using crown ether 18-crown-6 as an organic ligand in DMF solvent. The hybrid heterocomposite cocatalyst based on 1 and graphitic carbon nitride (g-C3N4) was prepared by a facile solvothermal method. In 1, the dimeric units Ag2I6 and Pb2I10 are joined via face sharing, leading to a ternary heterometallic 1-D [PbAg2I62-]n chain containing novel Ag2Pb2I4 cubes. The 1-D chains are joined by the discoid [Pb(18-crown-6)]2+ complex cations, forming the 2-D [Pb(18-crown-6)(PbAg2I6)]n hybrid with the skeleton of [Pb2Ag2I6]n. Compound 1 shows photocatalytic activity in the degradation of MB at room temperature under visible-light irradiation. The photoelectric response measurement showed that the photocurrent of 1 increased from 1.41 to 2.43 μA/cm-2 when g-C3N4 was loaded, indicating that the introduction of a certain amount of g-C3N4 on the surface of 1 improves the separation and migration rate of photoinduced electrons and holes. The 1/g-C3N4 composite showed much higher photocatalytic efficiency in comparison to pristine 1 and g-C3N4 for MB degradation, which suggests the synergistic effect between 1 and g-C3N4 toward visible-light-driven photocatalytic performance. Meanwhile, the 1/g-C3N4 composite exhibited good reusability and stability in the photocatalytic reaction. Free radical quenching experiments showed that the •O2- radical is the main reactive substance over catalyst 1, while h+, •OH, and •O2- species have synergistic effects over the 1/g-C3N4 composite catalyst in the process of photodegradation.

Green and efficient synthesis of Co-MOF-based/g-C3N4 composite catalysts to activate peroxymonosulfate for degradation of the antidepressant venlafaxine

Based on single metal–organic framework (MOF) composite catalyst ZIF-67/g-C3N4 (ZG), the composite catalysts ZIF-67/MOF-74(Ni)/g-C3N4 (ZNG) and ZIF-67/MIL-100(Fe)/g-C3N4 (ZMG) with double MOFs were synthesized, used to effectively activate peroxymonosulfate (PMS) for degrade venlafaxine (VEN). Various characterization methods (XRD, FT-IR, Raman, SEM, EDS, TEM and TG) showed that ZIF-67 and g-C3N4; ZIF-67, MOF-74(Ni) and g-C3N4; as well as ZIF-67, MIL-100(Fe) and g-C3N4 successfully formed heterostructures. The series of catalytic degradation results showed that within 120 min, the degradation rate of VEN by ZMG achieved 100% and the mineralization rate reached 51.32%. The removal rate of VEN by ZNG was 91.38%, while that by ZG was only 27.75%. Free radical quenching tests and EPR further confirmed the production of OH and SO4−, which could be conducive to the degradation of VEN. The mechanism analysis of PMS activation confirmed that the interaction of Fe2+/Co3+ was stronger than that of Ni2+/Co3+, and it was an important driving force to significantly enhance the synergistic effect. Finally, Gauss theory calculation and HPLC-MS/MS were used to analyze the intermediate products of VEN. It was verified that the main chemical reactions in the degradation process of VEN were hydroxylation, dehydration, demethylation and tertiary amine substitution.

A Novel CoO/PT-C3N4 Composite Catalyst for Photocatalytic Degradation of Diesel Oil

A Novel CoO/PT-C3N4 Composite Catalyst for Photocatalytic Degradation of Diesel Oil

Ni(OH)2/Ni/g-C3N4 composite: An efficient electrocatalyst for hydrogen evolution

The preparation of efficient catalysts in hydrogen evolution reaction (HER) is an urgent task at present. In this work, Ni(OH)2/Ni/g-C3N4 composite catalyst was prepared through liquid phase impregnation with in-situ reduction, which was used to compose the cathode with carbon paper (CP) for the microbial electrolysis cell (MEC). With the help of SEM, TEM, XRD, XPS and electrochemical analysis techniques, the structure, properties and electrocatalytic performance in hydrogen evolution of the Ni(OH)2/Ni/g-C3N4 composite were investigated. The results indicate that the Ni(OH)2/Ni/g-C3N4 catalyst exhibits excellent electrochemical activity for hydrogen evolution in the MEC. Using the Ni(OH)2/Ni/g-C3N4 catalyst, the current density reaches 100 A/cm2 at a small overpotential of 1881 mV, with a low charge transfer resistance of 10.86 Ω and a low Tafel slope of 44.3 mV/dec, which is much superior to pure g-C3N4 catalyst and CP, and even comparable to the Pt catalyst, suggesting that the Ni(OH)2/Ni/g-C3N4 composite can be a potential candidate of HER catalyst in MEC.

High efficiency photocatalytic degradation of indoor formaldehyde with silver-doped ZnO/g-C3N4 composite catalyst under the synergistic effect of silver plasma effect and heterojunction

Abstract Ag/ZnO/g-C3N4 ternary heterojunction structure was synthesized by a (hydrothermal reaction - calcination - reduction) three-step method. The combination of flake porous ZnO and fluffy porous g-C3N4 and silver makes the ternary composite catalyst exhibit good photocatalytic performance against formaldehyde pollutants. ZnO/g-C3N4 and Ag/ZnO/g-C3N4 catalysts can degrade formaldehyde to 74.1% and 81.2%, respectively. The photocatalytic activity of the ternary catalyst is 1.3 times and 2.6 times of that of pure ZnO and g-C3N4. The improvement of catalyst activity is mainly due to the synergistic effect of heterogeneous junction and plasma effect of metal silver. Heterojunction can effectively improve the charge transfer ability. The plasma effect of silver makes silver not only act as the electron transfer medium but also expand the photoresponse range of catalyst. Through the catalyst cycle experiment, it can be seen that the composite catalyst Ag/ZnO/g-C3N4 has good sustainable performance. In this experiment, the catalyst preparation method is simple and the raw materials are readily available, which provides a scheme that can be studied in depth for the effective removal of formaldehyde in the real environment.

Facile synthesis and enhanced photo-electrocatalytic performance of TiO2 nanotube/g-C3N4 composite catalyst by a novel synthesis approach

TiO2 nanotube/graphene-like carbon nitride (g-C3N4) composite structure was fabricated by a novel synthesis approach. Amorphous TiO2 nanotube arrays was synthesized by anodization. Afterward, g-C3N4 structures were decorated on the amorphous TiO2 nanotube arrays by using thermal polymerization process while anatase phase transformation of TiO2 in progress for the first time. The nanocomposite electrodes were further used for photo-electrochemical degradation of Rhodamine B dye. The homogenous surface morphology, higher crystallinity and more efficient photo-electrochemical performance were obtained by TiO2 nanotube/g-C3N4 composite structure due to better electrical contact and electron transportation by described synthesis approach.

Synthesizing Co3O4-BiVO4/g-C3N4 heterojunction composites for superior photocatalytic redox activity

In this study, a novel coral-like Co3O4-BiVO4/g-C3N4 ternary composite catalyst was successfully synthesized via high temperature polymerization and controlled hydrothermal reaction. In the Co3O4-BiVO4/g-C3N4 ternary hybrid system, the bulk Co3O4 particles were uniformly dispersed on the coral-like BiVO4 nanosheet, which not only enhanced to increase the response range and absorption to visible light, also contributed to suppress the recombination of photogenerated electron holes. The introduction of flocculent g-C3N4 increased the specific surface area of the catalytic system while accelerating the transmission efficiency of photogenerated carriers. After being illuminated for 90 min under the visible light, the degradation efficiency of pure BiVO4 and g-C3N4 catalysts were 81% and 80.2%, respectively. And the two binary catalysts, Co3O4-BiVO4 and BiVO4/g-C3N4 composite catalyst, performed the higher photocatalytic activity, which reached 94.8% and 96.8%, while ternary catalyst Co3O4-BiVO4/g-C3N4 composite catalyst showed the highest photocatalytic activity, the removal rate of KN-R was up to 99.6% after being irradiated for only 30 min with visible-light. Even more, its optical and electrochemical properties were greatly improved, making it as a forceful candidate for practical photocatalysts under visible light. In summary, this work not only provided a highly efficient heterojunction-structured visible-light photocatalyst, but also supplied a novel method to diminish the photo-carriers recombination.

Visible-light responsive g-C3N4 coupled with ZnS nanoparticles via a rapid microwave route: Characterization and enhanced photocatalytic activity

Visible-light responsive g-C3N4 catalysts were successfully prepared by the calcination of urea, i.e., the thermal polycondensation method, and a series of ZnS/g-C3N4 composite photocatalysts were then synthesized using a rapid microwave hydrothermal method. The physicochemical properties of the resulting g-C3N4 and ZnS/g-C3N4 catalysts were characterized via several microscopy and spectroscopy techniques. The reduction of Cr(VI) was used to evaluate the photocatalytic performance of the as-synthesized catalysts under visible light irradiation. The results showed that the calcination temperature substantially affected the crystallinity, specific surface area and photocatalytic performance of g-C3N4. The optimal temperature for thermal polycondensation in the g-C3N4 synthesis was 600 °C. The bulk g-C3N4 catalyst exhibited no Cr(VI) reduction ability, while a certain amount of ZnS nanoparticles coupling with g-C3N4 significantly improved the Cr(VI) reduction efficiency, creating a synergistic effect between g-C3N4 and ZnS. The simultaneous Cr(VI) reduction and rhodamine B decolorization by the ZnS/g-C3N4 composite catalyst were also accomplished. In addition, a Cr(VI) reduction mechanism under visible light irradiation was proposed.

Concerted catalytic and photocatalytic degradation of organic pollutants over CuS/g-C3N4 catalysts under light and dark conditions

Organic pollutants in industrial and agricultural sewage are a serious threat to the environment and human health. Achieving continuous photocatalytic degradation of organic pollutants under light and dark conditions would have exciting implications for practical sewage treatment. In this paper, CuS/g-C3N4 composite catalysts with CuS nanoparticles anchored on g-C3N4 sheets were successfully fabricated via a simple solvothermal reaction. The morphology, structure, optical absorption characteristics, electron–hole recombination rate, and degradation performance of the as-prepared CuS/g-C3N4 catalysts were investigated in detail. The results confirmed that the as-fabricated CuS/g-C3N4 catalysts exhibited high Fenton-like catalytic degradation efficiencies in the dark, and rapid concerted Fenton-like catalytic, direct H2O2 photocatalytic and CuS/g-C3N4 photocatalytic degradation activities under visible light. Thus, the as-fabricated CuS/g-C3N4 catalysts can degrade organic pollutants continuously during both day and night. These degradation properties, along with the simple catalyst fabrication process, will facilitate the practical application of this system in the continuous removal of organic pollutants.