Photocatalytic Degradation Ability Research Articles

Purification of textile wastewater by collective degradation using nanorods of cesium titanium bromide (CsTiBr3) perovskite

The present work recommends a sustainable environmentally safe method for the removal of textile dyes in an economically viable way.The wastewater expelled from the textile dying units contains a mixture of dyes. Here we address the challenge of using a single catalyst for the collective photocatalytic degradation of mixture of six dyes and two samples of textile effluents collected from a local dying unit under direct sunlight. The lead-free perovskite of CsTiBr3 nanorods prepared via the solvothermal process is effective in the collective photocatalytic degradation of dye mixture containing toxic dyes like congo red, crystal violet, malachite green, methylene blue, rhodamine, and methyl orange. The six-dye mixture turned colorless within three hours of direct sunlight exposure. The collective photocatalytic degradation ability of CsTiBr3 perovskite nanorods is successfully exploited for the degradation of the textile effluents. The chemical oxygen demand (COD) analysis guarantees the degradation of dye into non-toxic components. The recycling of wastewater is made possible by the removal of CsTiBr3 catalysts through adsorption using biochar derived from invasive plants. The biochars are extracted from invasive plants such as Acrostichum Aureum, Alternanthera bettzickiana, cyclosorus interrupts, and Quisqualis indica in which Acrostichum Aureum showed maximum adsorption. The scavenger studies using isopropyl alcohol (IPA), ethylene diamine tetra acetic acid (EDTA), and silver nitrate (AgNO3) suggest that holes control the photocatalysis mechanism.

Europium (III)-modified sunflower-derived carbon dots for fluorescent anti-counterfeiting inks and photocatalysis.

A highly water-soluble and fluorescent N,S-doped carbon dots/europium (N,S-CDs/Eu) was successfully synthesized via a secondary hydrothermal method. This involved surface modification of N,S-CDs derived from sunflower stem pith (SSP) with europium ions (Eu3+) doping. When excited within the range of 400-470 nm, N,S-CDs/Eu exhibited a stable and broad optimal emission wavelength ranging from 505 to 540 nm. Notably, the photoluminescence quantum yield (PLQY) of N,S-CDs/Eu is 31.4%, significantly higher than the 19.5% observed for N,S-CDs. Additionally, by dissolving N,S-CDs/Eu into polyvinyl alcohol (PVA), a uniform fluorescent anti-counterfeiting ink can be prepared. The N,S-CDs/Eu/TiO2 composite demonstrates excellent photocatalytic degradation ability towards the organic dye methylene blue (MB). N,S-CDs/Eu has potential in the field of fluorescent inks and photocatalysis due to its simple and efficient preparation and excellent properties.

Reduced Ag NPs-modified NaTaO3 layer improves photocatalytic degradation and antimicrobial ability through LSPR effect and doping behavior

Reduced Ag NPs modified Ag-doped NaTaO3 layer photocatalysts were prepared using the hydrothermal method. The research investigated the microstructure and degradation ability of composite layer containing Ag-NaTaO3. Various techniques, including SEM,TEM, XRD, UV–Vis and PL analyses, were used for the evaluation. The antibacterial effect of the Ag-NaTaO3 layers on Staphylococcus aureus (S. aureus) before and after modification with reduced Ag NPs was evaluated. The Ag-NaTaO3 composite layer showed stronger degradation effect and bactericidal activity than NaTaO3 under the optimal conditions (Concentration of Ag+-containing solution 0.1 mol/L, reaction temperature 200 ℃, reaction time 3 h). The degradation efficiency of Ag3-NaTaO3 for MB was 87.6 % after 50 min, and the bactericidal inhibition rate was 100 % after 20 min. The degradation process, with electron hole (h+) as the main active substance, conforms to the first-order kinetic with a rate constant (K) value of 0.0310 min−1. The band gaps (Eg) of the calculated pure phase NaTaO3 and Ag3-NaTaO3 are 3.18 eV and 2.75 eV, correspondingly. The fluorescence decay spectra indicate that the average expected lifetimes of Ag3-NaTaO3 composites rounded is 11.45 ns, respectively. The NaTaO3 nano-cubic structure, prepared using Ta2O5 precursor, reduces the grain size, provides more surface active sites, and effectively improves the range of the NaTaO3 photoresponse. AgNO3 solution is used to reduce Ag NPs and carry out doping behavior. The LSPR behavior of Ag NPs and the doping behavior of Ag lower the Schottky barrier that is made up of the metal–semiconductor interface. This ensures that the hot metal electrons are injected into the semiconductors efficiently, improves the electron-hole (h+) separation efficiency, and enhances the photocatalytic activity. The bacterial structure was destroyed through a dual mechanism of reactive oxygen species (ROS) (·OH, ·O2–) and Ag properties, achieving excellent bacterial inhibition. This study proposes a new concept to enhance the photocatalytic performance of NaTaO3 thinfilm materials, which will could have significant applications in the field of wastewater treatment.

Synthesis, structure, theoretical calculation and photocatalytic property of a novel Mn(II) supra-molecular compound containing SCN- and 2,2′-bipyridine ligands

A novel supra-molecular compound [Mn(SCN)2(byp)2] 1 (byp = 2,2′-bipyridine) was synthesized under hydrothermal conditions. Noteworthily, the SCN- in the title compound is derived from the in situ reaction of salicylaldehyde thiosemicarbazone. X-ray single-crystal diffraction analysis shows compound 1 is only a mononuclear structure, but it is expanded into a 3D supramolecular structure via H-bonds and π···π stacking. Hirshfeld Surface analysis shows C⋯H, H⋯H and S⋯H interaction are the main contribution of intermolecular interactions in the formation of compound 1. All of title compounds were characterized by IR spectroscopy, elemental analysis, XRD, XPS and TG analysis. The energy framework of compound 1 is dominated by dispersion interaction. The photocatalytic degradation ability of compound 1 for methylene blue is verified by photocatalytic degradation experiments (pH = 4: 44.6 %; pH = 7: 76.2 %; pH = 10: 78.8 %). Furthermore, the potential photocatalytic mechanism of compound 1 is inferred by UV–vis absorption spectra and Mott–Schottky curve.

Magnetically-manipulatable and self-cleaning lab-on-a-bubble Ag@TiO2@Fe3O4 hollow spheres and their application in SERS detection and photocatalytic degradation

In this study, an innovative highly sensitive self-cleaning Lab-on-a-bubble SERS substrate: Ag NPs@TiO2@Fe3O4 hollow spheres, was developed using spray pyrolysis and following depositions. The reusable and magnetically controllable substrate consists of iron oxide hollow spheres (Fe3O4) covered by a TiO2 shell and silver nanoparticles (Ag NPs) deposited on the outer surface. Experimental results show that this new composite SERS substrate exhibited a low limit of detection (LOD) down to 10-10M, and the enhancement factor (EF) reached 1.01 X107. It suffered only 3 % loss after 10 repeatable recycle tests if the self-cleaning under UV was performed after each test. This novel substrate possessed good photocatalytic degradation ability for methylene blue (MB) dyes even under visible light. In that case, MB can be dissociated up to 99.8 % and the reaction rate constant (K) reached 0.0271/min. Taking advantage of this, the feasibility of reusable SERS detection through self-cleaning under visible light was also demonstrated.

Electrochemical remediation of methyl orange over reusable biochar ferrite coated photocatalytic plates

Biochar (BC) obtained from biomass pyrolysis holds immense potential for environmental remediation. The efficiency of BC can further be enhanced by incorporating metal nanoparticles (NPs) in the porous carbon matrix. In the present work nanocomposites (NCs) were prepared by the addition of ferrite nanoparticles (FNPs) into an oxidized BC matrix to create BC /Fe3O4 (BCF). This process improves BC stability, electron transfer, conductivity, and photocatalytic ability for dye degradation. Microstructure and functional group analysis of BCF was performed by SEM, XRD, and FTIR showing intercalation of FNPs with surface functionalities of oxidized BC matrix. The B-H curve of FNPs and BCF reveals super paramagnetic behavior with saturation magnetization (Ms, emu/g) of 67.36 and 20.01 respectively. BET surface area analysis shows surface area (m2/gm) 45.81 and 44.19 for oxidized BC and BCF respectively, that attributed to partial blocking of porous carbon matrix by FNPs. UV-DRS supports the semiconducting behavior of BCF with a significantly reduced band gap (eV) of 2.95 over pristine BC (4.76). BCF-coated photocatalytic plates (PCPs) were developed and utilized for the remediation of methyl orange (MeO) in water samples. Degradation of MeO was investigated over time by electrochemical methods. The square wave voltammetric method showed the limit of detection and quantification of 0.09 ppm and 0.28 ppm respectively for MeO over a glassy carbon electrode in 0.1 M acetate buffer. BCF-derived PCPs rendered ∼99 % degradation efficiency against MeO (50 mgL−1) under UV radiation over 240 min. Developed PCPs demonstrate reusability up to 5 cycles without any further purification step and offer efficient degradation of MeO making them suitable for the treatment of water polluted with dyes.

Eco-friendly and sustainable synthesis of carbon quantum dots from waste sulfuric acid of alkylation

Waste sulfuric acid of alkylation (WSAA) poses a challenge in industrial alkylation oil production due to its substantial yield and high treatment costs. This study introduces a novel hydrothermal method that ingeniously couples the treatment of WSAA with the synthesis of high-quality carbon quantum dots (CQDs), offering a cost-effective and controllable approach. Through this method, the particle size and surface functional groups of the resulting CQDs can be precisely regulated. The average particle size tunes from 17.97 nm to 2.42 nm via increasing the hydrothermal temperature, and nitrogen-containing groups can be introduced through adding nitrogen sources during hydrothermal process. The prepared CQDs exhibit notable performance in photocatalysis and heavy metal detection, such as CQDs modified graphite carbon nitride has improved photocatalytic degradation ability and Hg (II) detection ability. Additionally, the environmental impact of the proposed method is substantially minimized, demonstrating a smaller footprint on ecosystems compared to conventional industrial disposal processes. Moreover, the economic cost associated with the method is significantly reduced by approximately 48.4 %, further highlighting its efficiency. Utilizing WSAA as a raw material for CQDs not only facilitates the recycling and sustainable utilization of waste but also enables low-cost production of high-performance carbon materials, presenting a mutually beneficial approach.

Introducing the antibacterial and photocatalytic degradation potentials of biosynthesized chitosan, chitosan–ZnO, and chitosan–ZnO/PVP nanoparticles

The development of nanomaterials has been speedily established in recent years, yet nanoparticles synthesized by traditional methods suffer unacceptable toxicity and the sustainability of the procedure for synthesizing such nanoparticles is inadequate. Consequently, green biosynthesis, which employs biopolymers, is gaining attraction as an environmentally sound alternative to less sustainable approaches. Chitosan-encapsulated nanoparticles exhibit exceptional antibacterial properties, offering a wide range of uses. Chitosan, obtained from shrimp shells, aided in the environmentally friendly synthesis of high-purity zinc oxide nanoparticles (ZnO NPs) with desirable features such as the extraction yield (41%), the deacetylation (88%), and the crystallinity index (74.54%). The particle size of ZnO NPs was 12 nm, while that of chitosan–ZnO NPs was 21 nm, and the bandgap energies of these nanomaterials were 3.98 and 3.48, respectively. The strong antibacterial action was demonstrated by ZnO NPs, chitosan–ZnO NPs, and chitosan–ZnO/PVP, particularly against Gram-positive bacteria, making them appropriate for therapeutic use. The photocatalytic degradation abilities were also assessed for all nanoparticles. At a concentration of 6 × 10–5 M, chitosan removed 90.5% of the methylene blue (MB) dye, ZnO NPs removed 97.4%, chitosan-coated ZnO NPs removed 99.6%, while chitosan–ZnO/PVP removed 100%. In the case of toluidine blue (TB), at a concentration of 4 × 10–3 M, the respective efficiencies were 96.8%, 96.8%, 99.5%, and 100%, respectively. Evaluation of radical scavenger activity revealed increased scavenging of ABTS and DPPH radicals by chitosan–ZnO/PVP compared to individual zinc oxide or chitosan–ZnO, where the IC50 results were 0.059, 0.092, 0.079 mg/mL, respectively, in the ABTS test, and 0.095, 0.083, 0.061, and 0.064 mg/mL in the DPPH test, respectively. Moreover, in silico toxicity studies were conducted to predict the organ-specific toxicity through ProTox II software. The obtained results suggest the probable safety and the absence of organ-specific toxicity with all the tested samples.

Solution combustion synthesis and exploration of chromium reduction and organic dyes degradation of cobalt tungstate (CoWO4) nanoparticles

Facile preparation route for cobalt tungstate (CoWO4) via cost effective, time saving, easy and solution combustion approach is described in the present paper. The structural, morphological properties of cobalt tungstate characterized by different physiochemical techniques which include X-ray diffraction, scanning electron microscopy (SEM), energy dispersive X-ray absorption (EDS). The optical properties assessed by UV–visible spectroscopy (DRS) and photoluminescence spectroscopy (PL). Using these methods, it was discovered that CoWO4 which has been synthesized displayed a monoclinic phase of Wolframite with great crystallinity and purity. The average crystallite size of prepared CoWO4 was 22 nm and band gap obtained was 2.84 eV due to which it can be used as visible light photocatalyst in aqueous medium. As a result, in this study, the photocatalytic degradation ability of CoWO4 was assessed by observing the aqueous phase degradation of the most widely used dyes, methylene blue (MB) and Rhodamine-B as well as Cr(VI) reduction under visible light. Almost all MB degraded in 90 min whereas 69 % degradation of RhB takes place in 240 min under visible light irradation. The different aspects for low rate of photodegradation of RhB dye than MB dye was also discussed in this report. The present study deals advanced approach that CoWO4 can also be used as capable visible light photocatalyst for degradation of dangerous contaminants and for reduction of carcinogenic Cr(VI) into nontoxic Cr(III) from waste water.

Construction of direct-Z-scheme heterojunction photocatalyst of g-C3N4/Ti3C2/TiO2 composite and its degradation behavior for dyes of Rhodamine B

Direct-Z-scheme g-C3N4/Ti3C2/TiO2 photocatalyst with giant internal electric field were prepared by one-step aqueous sonication self-assembly method using g-C3N4 and MXene of Ti3C2 as the source materials. The chemical composition and structure of the catalysts was characterized by FT-IR, XRD, SEM, TEM and XPS. The XPS characterization indicated that Ti3C2 was partially oxidized to TiO2 during the composite process. As a result, an efficient direct-Z-scheme heterojunction structure consisting of the g-C3N4 and TiO2 with Ti3C2 as an electron bridge was constructed. The photocatalytic performance of the prepared catalysts was evaluated by degrading the rhodamine B (RhB) wastewater. Compared with the single g-C3N4, the g-C3N4/Ti3C2/TiO2 composite photocatalyst exhibited efficient and stable photocatalytic degradation ability, with a degradation efficiency as high as 99.2% for RhB under optimal conditions (2% Ti3C2, pH=3). The high degradation performance of g-C3N4/Ti3C2/TiO2 for RhB was attributed to the combination of Ti3C2, TiO2, and g-C3N4 components, forming a direct-Z-scheme heterojunction with a high-speed electron transport channel structure. The role of Z-scheme heterojunctions in electron transport is verified by photoelectrochemical characterization, along with photoluminescence (PL). Our research provides a simple method to design photocatalysts by constructing direct-Z-scheme electron transport channels for highly efficient treatment of dye wastewater.

High performance Zn–Al LDH modified forward osmosis membrane with antibacterial, anti-membrane fouling, and photocatalytic degradation ability

Forward osmosis membrane has shown great potential in the fields of seawater desalination and sewage treatment. However, the concentration polarization phenomenon and membrane fouling in the water treatment process greatly reduce the water treatment performance and restrict its application. To address these challenges, we employed a pre-buried seed-in-situ growth method to facilitate the Zn–Al layered double hydroxide (Zn–Al LDH) growth on the thin nanofiber membrane, and use it as the support layer for the preparation of a Zn–Al LDH modified forward osmosis membrane. Studies have shown that the introduction of Zn–Al LDH significantly improves the water treatment efficiency of the forward osmosis membrane (In Al-DS mode, the water flux increased by 87.5 %, up to 50.50 LMH, with a low specific salt flux of 0.13 g L−1). It also exhibits exceptional antibacterial, anti-membrane fouling, and photocatalytic degradation properties. This research presents a novel approach for the development of advanced high-efficiency forward osmosis membranes.

Superhydrophilic PANI/Ag/TA@PVDF Composite Membrane with Antifouling Property for Oil-Water Separation.

The current membrane materials used for oil-water separation suffer from low separation efficiency and poor durability, and membrane contamination is also a key issue that must be addressed urgently. In this paper, a superhydrophilic PANI/Ag/TA@PVDF composite membrane with PANI-Ag NPs heterojunction structure was prepared via chelation and reduction of Ag+ by tannic acid (TA) and in situ growth of hydrochloric acid-doped polyaniline (PANI). TA endows the prepared composite membrane with excellent superhydrophilicity and underwater oleophobicity, remarkable oil-water separation capacity (the separation efficiency of more than 97% for soybean oil), and extraordinary antifouling properties. Notably, the range of photodegradation is expanded from UV to visible light by the construction of a Schottky heterostructure between PANI and Ag NPs, the photocatalytic degradation ability of composite membrane for organic pollutants has been improved obviously, and the degradation efficiency for crystal violet (CV) is 97.9%. Considering these merits, the PANI/Ag/TA@PVDF composite membrane provides an effective strategy to overcome the shortcomings of existing membrane materials, presenting enormous potential in the treatment and purification of oily wastewater.

Study of the Structure and Photocatalytic Degradation Ability of a New Complex Manganese

Study of the Structure and Photocatalytic Degradation Ability of a New Complex Manganese

Green synthesis of gold nanoparticles using macroalgae Halimeda macroloba extract and their photocatalytic degradation of methylene blue and methyl orange

AbstractGreen synthesis of gold nanoparticles (AuNPs) is gaining attention of researchers because of their varieties of biomedical and environmental applications. This study reported the novel eco‐friendly synthesis of AuNPs using green macroalgae Halimeda macroloba (HM) extract and evaluate their photocatalytic potential. The green synthesized H. macroloba mediated gold nanoparticles (HM‐AuNPs) was characterized using UV–visible spectrophotometry, Fourier‐transform infrared (FT‐IR) spectroscopy, transmission electron microscope (TEM), scanning electron microscope‐energy dispersive spectroscopy, x‐ray photoelectron spectroscopy (XPS), and particle size distribution (PSD) anlaysis. The UV–visible spectrum shows a sharp intense plasmonic resonance peak at 543 nm. The bioactive compounds present in HM were primarily responsible for the biological reduction of gold ions validated by FT‐IR analysis. XRD analysis proved the crystalline face centered cubic structure of the HM‐AuNPs. The average particle size of 18.72 nm and morphological evidences were obtained from the images from TEM. The metallic form of biosynthesised HM‐AuNPs was confirmed by XPS results with a distinctive binding energy. The photocatalytic degradation ability of the green synthesized HM‐AuNPs was investigated against the methylene blue (MB) and methylene orange (MO) dyes under sunlight irradiation. The HM‐AuNPs exhibited 97.23% and 89.91% photocatalytic activity against MB and MO after 90 min of exposure to sunlight, respectively. The overall results of this research indicate that H. macroloba mediated HM‐AuNPs can be used as an effective option for the degradation of industrial dyes.

NOx degradation by cement mortar containing B-TiO2/MgAl-CLDH under visible light: Experimental and modeling

In this paper, an advanced photocatalyst, B-TiO2/MgAl-CLDH, was synthesized and applied in cement mortar. The photocatalytic NOx degradation ability of cement mortar containing B-TiO2/MgAl-CLDH under different initial NOx concentrations and flow rates was investigated. The results show that B-TiO2/MgAl-CLDH has stronger visible light absorption, lower recombination rate of electron-hole pairs and narrower optical band gap than commercial nano-TiO2 (P25), resulting in enhanced NOx removal efficiency. Specifically, the maximum NOx degradation ratio of B-TiO2/MgAl-CLDH is 23.4% within 30 min, which is about 5 times that of P25. For photocatalytic mortar, the initial NOx concentration (from 1.0 ppm to 2.0 ppm) and flow rate (from 1 L/min to 3 L/min) were positively correlated with NOx removal amount, while negatively correlated with NOx removal ratio. Based on the internal molecular diffusion properties of NOx, Langmuir-Hinshelwood and the power law kinetic models were used to predict the NOx degradation ability of photocatalytic mortar. The modeling of NOx degradation process presents a reliable prediction of the NOx removal ability of photocatalytic mortar, serving as a valuable tool for assessing the mortar’s NOx removal effectiveness for policymakers and engineers.

Biogenic synthesis, characterization and photocatalytic activity of cerium nanoparticles for treatment of dyes contaminated water

In this study, Murraya Koenigii leaf extract mediated cerium oxide nanoparticles (Ce-NPs) were synthesized using an eco-friendly approach. The surface morphology, elemental composition, surface functional groups, crystal structure and thermal stability of the synthesized Ce-NPs were examined using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), X-Ray diffraction (XRD) and thermogravimetric (TGA) analysis. The synthesized Ce-NPs were evaluated for their photocatalytic activity with respect to degradation of methylene blue dye (MBD) and acid orange-7 dye (AO7D) aqueous solution in the presence of sunlight. The dye degradation activity of the developed Ce-NPs was analyzed by the analysis of absorbance in treated and untreated aqueous dyes solution using UV–Vis spectrophotometer. The result of the study inferred that Ce-NPs have promising photocatalytic degradation ability (>98 %) for both AO7D and MBD (concentration = 10 mg L−1 of each dye) within 100 min exposure to sunlight.

Comprehensive investigations into the synergy of S-scheme heterojunction between nitrogen-doped ZnO nano-rods and g-C3N4 nanosheets for improved photocatalytic degradation

In this work, N-ZnO nanorods decorated with 2D g-C3N4 prepared by hydrothermal synthesis are studied for their synergistic effect in regard to enhanced photocatalytic activity. The synthesized material is characterized with XRD, FESEM, EDX, TEM and HR-TEM to perform the structural, morphological and elemental analysis along with XPS and FTIR for tracking sample purity and to study the elemental composition on the surface of the material; UV–Visible spectroscopy and PL spectroscopy for investigating the optical properties, bandgap calculation and to inquire about the defects in the structure. N-ZnO/g-C3N4 shows remarkable photocatalytic MB degradation ability upon solar irradiation which is 2.8 and 1.2 times exceeds than pristine ZnO and g-C3N4, attributed to the s-scheme mechanism for charge migration. The construction of s-scheme heterojunction among N-ZnO and g-C3N4 generates an internal electric field that saliently promotes charge separation at the interface. Furthermore, post-stability test for 8 cycles with XRD and FTIR analysis to verify the material integrity is presented. The scavenger experiments revealed the involved active species. This research does seem to pique interest in the creation of cutting-edge photocatalysts that utilize the solar spectrum to remove harmful organic dyes from water.

A magnetically recyclable Fe3O4/ZnIn2S4 type-II heterojunction to boost photocatalytic degradation of gemifloxacin

In this study, a magnetic recyclable Fe3O4/ZnIn2S4 flower-like heterojunction photocatalyst was successfully constructed by means of a hydrothermal method. It not only exhibited an enlarged the specific surface area, but also improved the absorption of visible light, which greatly enhanced the photocatalytic degradation ability. The results of the photocatalytic activity tests showed that the maximum rate (0.01903 min−1) of degradation of gemifloxacin (GMF) by Fe3O4/ZnIn2S4 was significantly increased by 1.67 and 23.79 times compared with those of pure ZnIn2S4 and Fe3O4, respectively. Based on the difference in Fermi energy levels between ZnIn2S4 and Fe3O4 and the electron gain/loss of the elements of the Fe3O4/ZnIn2S4 heterojunction, a type-II electron transfer mechanism was proposed to illustrate that the Fe3O4/ZnIn2S4 heterojunction improved the photocatalytic activity by promoting the separation and transfer ability of the photogenerated carriers. By combining liquid chromatography mass spectrometry -ion trap-time of flight technology and a condensed Fukui function, a possible degradation mechanism of GMF was proposed.

Oxygen Functionalized Graphitic Carbon Nitride for Photocatalytic Degradation of Dye

Photocatalyst such as graphitic carbon nitride (g-C3N4) is being studied intensively due to its ability in photocatalysis. g-C3N4 is a metal-free semiconductor photocatalyst with a bandgap of approximately 2.7 eV which contributes to its good visible light harvesting ability. In this work, bulk g-C3N4 was produced via pyrolysis of melamine in a muffle furnace. Functionalized g-C3N4 with improved properties was synthesized via modified Hummers method. The powdered form of functionalized g-C3N4 were characterized using SEM and EDX to identify its physiological properties. The result showed that the introduction of oxygen into g-C3N4 is proven by the increased content of oxygen in the functionalized g-C3N4 upon oxidation using Hummers method. Besides, exfoliation of g-C3N4 to smaller particle size observed from the SEM images. Then, the phototcatalytic performances of the bulk g-C3N4 and functionalized g-C3N4 were evaluated by degrading of Methylene Blue (MB) dyes under LED light irradiation. The result revealed that the bulk g-C3N4 has a higher efficiency in removal of dyes (56.40 % in 150 minutes) than the functionalized g-C3N4 (22.60 % in 150 minutes) which indicates that it has a better photocatalytic degradation ability, which possibly due to the destruction of compound structure under strong acid treatment.

A synergistically enhanced photocatalytic 2D MXene nanofibrous composite membrane for wastewater treatment

Despite notable advancements in membrane technology, the efficacious separation of intricate oily wastewater via membrane filtration continues to pose formidable barriers for the industry. Recent methods, encompassing the integration of two-dimensional (2D) nanosheets to improve membrane properties, have demonstrated a propensity for encountering challenges like swelling, fouling, and operational instability during the filtration process. Herein, we meticulously designed a polyvinylidene fluoride (PVDF) nanofibrous membrane (NFM) tailored with a 2D nanostructured composite of MXene nanosheets and TiO2 nanofrost for the pioneering treatment of intricate oily wastewater. The resultant membrane exhibited remarkable separation performance concerning surfactant-stabilized emulsions while maintaining excellent water permeability. Additionally, the membrane demonstrated outstanding antifouling and self-cleaning capabilities while also showing high efficiency in removing metal cations from oily wastewater, which may be related to the intercalation of TiO2 nanofrost. Furthermore, in response to the synergistic impact of MXene nanosheets and TiO2 nanofrost, the TiO2@MX-PVDF NFM presented exceptional photocatalytic degradation ability for the breakdown of organic pollutants under visible irradiation. Consequently, present work unveils an advanced, reliable and remarkably efficient approach for developing a 2D multifunctional MXene composite membrane designed specifically for treating complex oily wastewater.