Methyl Orange Research Articles

1 T/2 H mixed phase MoS2 nanosheets decorated with Ag nanoparticles for effective photocatalysis of organic dyes for wastewater treatment

The rapid industrialization and urbanization have led to the proliferation of organic dyes in wastewater, necessitating the development of efficient and sustainable treatment technologies. We report here a novel photocatalyst based on 1 T/2 H mixed-phase molybdenum disulfide nanosheets (1 T/2 H-MoS2 NSs) decorated with silver (Ag) nanoparticles for the enhanced photodegradation of both cataionic and anionic organic dyes under natural sunlight. Hydrothermally synthesized silver nanoparticles decorated 1 T/2 H MoS2 nanosheets (Ag-1 T/2 H MoS2 NSs) are characterized through X-ray diffraction (XRD), Field Emission Scanning Electron Microscopy (FESEM), Transmission Electron Microscopy (TEM), Raman spectroscopy, UV–vis spectroscopy, and Photoluminescence (PL) spectroscopy. FESEM results reveal that MoS2 NSs of thickness 17 nm clustered into nanoflowers where Ag nanoparticles are embedded in them. XRD results show the characteristic diffraction peaks at 2ϴ value 9.80 and 32.380 for (002) and (100) planes respectively. Photocatalytic performance has been evaluated by the degradation of Crystal Violet (CV) and Methyl Orange (MO) under direct sunlight irradiation. Nanocomposites exhibit a significant improvement in degradation efficiency i.e. 97 % for both (CV) and (MO) in 15 minutes and 25 minutes respectively compared to pure MoS2. The superior activity of the Ag-1 T/2 H MoS2 composite is attributed to the synergistic effects of the mixed-phase MoS2 structure and the charge transfer phenomenon provided by Ag nanoparticles. This work highlights the potential of Ag-1 T/2 H MoS2 NSs as an effective photocatalyst for the treatment of dye-contaminated wastewater.

Synthesis of N-alkyl azoles carrying metal complexes for catalytic and medicinal applications

Drastic increase in water pollution due to industrial waste specifically dyeing reagents that are disturbing the water cycle ultimately may vanish the aquatic and human life. The current study focused on the synthesis of N-alkylated imidazole’s derivatives and their complexes; tetrakis(3-propyl-2,3-dihydro-1H-imidazol-1-yl)cerium(III) nitrate/C1 and tetrakis(3-butyl-2,3-dihydro-1H-imidazol-1-yl)cerium(III) nitrate/C2 with cerium(III) hexahydrate nitrate. Structural confirmation and chemical environment of synthesized products were confirmed by using FT-IR, FT-Raman, and NMR spectroscopic techniques. Synthesized complexes were evaluated as catalyst by using various independent variables like contact time, dose of catalyst and concentration of catalyst for degradation of Methyl Orange (MO) and Murexide (MX). RSM analyses via Central Composite Design (CCD) model of all these variables were designed and average degradation efficiencies were calculated in the range of 80–90 % that made the synthesized complexes fantastically fit for catalytic applications. Moreover, the ligands used in syntheses of complexes possessed characteristics to inhibit the growth of mutated cells of prostate and HeLa cell lines. Their IC50 values L1, L2, C1 and C2 were observed in the range of 21.3–23.6 µl for PC3 cell line and 12.72–19.51 µl for HeLa cell lines and compared with reported drug called Doxorubicin (Control). Thus, the syntheses of L1, L2, C1, and C2 successfully encountered the need of the concerned issues. They possessed extra-ordinary catalytic (about 84–94 % degradation of textile dyes) and pharmacological (anticancer activity against HeLa cell line and PC3 cell line) potential.

Development of a novel lightweight brick-activated carbon based BiVO4 photocatalyst and its adsorption-photocatalytic behavior for toxic dye removal in wastewater

The purpose of this research was to develop a novel photocatalyst by loading BiVO4 (BVO) particles on lightweight brick-activated carbon (LWB-AC). The characterizations of as-prepare samples were studied using X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and UV–VIS –NIR spectrophotometer (UV-VIS-NIR) techniques. The adsorption-photocatalytic methylene blue (MB) removal, methyl orange (MO) removal and rhodamine B (RhB) removal of the as-prepared LWB-AC based BVO photocatalyst were tested by irradiating visible light. The results showed that the LWB-AC based BVO photocatalyst exhibited the highest adsorption-photocatalytic efficiency for the removal of MB, MO and RhB dyes under visible light irradiation as compared to the other samples. This might be due to the synergistic effect between AC and BVO on the surface of LWB. Moreover, the presence of both AC and BVO on the surface of LWB helped in preventing the electron-hole recombination, resulting in the enhanced adsorption-photocatalytic activity. For reusability tests, the LWB-AC based BVO photocatalyst did not show the loss of adsorption-photodegradation ability of MB, MO and RhB dyes after five runs. A probable adsorption-photodegradation mechanism of LWB-AC based BVO photocatalyst was also proposed.

The effect of phosphoric acid on the properties of activated carbons made from Myrtus communis leaves: Textural characteristics, surface chemistry, and capacity to adsorb methyl orange

In this work, chemical activation was employed to produce activated carbons and assess the impact of phosphoric acid (H3PO4) on their physicochemical properties. Using Myrtus communis Leaves (MC-Leaves) as the precursor and varying H3PO4 impregnation ratios (30 %, 60 %, 100 %, and 150 wt.%). The activation was conducted at 450 °C (10 °C/min) for 1 h in a room atmosphere. The effects of H3PO4 were evaluated through various techniques, including BET surface area analysis, FESEM-EDS imaging, XPS, FT-IR-ATR, Raman spectroscopy, CHNS-(O) elemental analysis, and Methyl orange (MO) adsorption studies. The specific surface area (SSA) and total pore volume increased from 642m2/g to 1237m2/g, total pore volume increased from 0.29cm3/g to 0.97cm3/g, and the mean pore diameter increased from 1.9 nm to 3.2 nm by increasing the impregnation ratio from 30 wt.% to 150 wt.%. The pH(pzc) of MC-ACs exhibited an acidic character, owing to the presence of oxygen-containing functional groups such as hydroxyl, carboxyl, metaphosphate (-PO3-), phosphates, and pyrophosphate groups, as indicated by XPS and FT-IR analysis. At a room temperature of 22 °C and an ideal pH of 2.06, the maximum adsorption capacity (qmax) rose from 46.02±4.63 mg g-1 to 326.54±37.67 mg g-1 as the impregnation ratio increased from 30 wt.% to 150 wt.%. Freundlich isotherm well explained the adsorption equilibrium at 22 °C for all MC-ACs. The effect of temperature illustrates that the adsorption of MO onto MC-AC30 % was endothermic, while the adsorption of MO onto MC-AC150 % was an exothermic. The kinetic study was conducted at 22 °C, when the equilibrium time was at 4hours, and it was a pseudo-second order (PSO) model.

Facile synthesis of novel cobalt molybdenum sulfide-graphitic carbon nitride (CoMoS4/g-C3N4) nanocomposite electrode for improved supercapacitor and photocatalytic applications

Supercapacitors have gained significant attention from scientists due to their wide range of applications in energy storage devices. However, searching for abundant and eco-friendly materials on earth is still necessary while preserving their outstanding performance. Herein, cobalt molybdenum sulfide-graphitic carbon nitride (CoMoS4/g-C3N4) nanocomposite was synthesized to explore an exceptional electrode material for energy and photocatalytic applications. The structural analysis, vibrational modes, and porosity within the CoMoS4/g-C3N4 nanocomposite were studied by XRD, Raman, and SEM. The direct energy band gap decreased from 2.54 to 2.44 eV along with the increased ratio of CoMoS4 in the nanocomposite. The electrochemical measurements of CoMoS4/g-C3N4 nanocomposite exhibited an excellent specific capacitance (Cp) of 3675 F/g at 1 mV/s and 3150 F/g at 2.5 A/g with noticeable specific energy density (Eg) of 109.4 Wh/kg, high power density (Pd) of 625 W/kg and retain high capacitance (88 % of its initial value) even after 4000 cycles. Furthermore, the photocatalytic results revealed that high photodegradation efficiency (97.85 %) was attained against methyl orange (MO) dye under UV light irradiation. Prepared electrode materials are promising materials for next-generation energy storage and environmental applications.

Rational design of Zn4O(BDC)3 metal organic framework incorporated with NiCr2O4 nanoparticles: An affordable photocatalyst for the degradation of hazardous dyes

In this work, a simple hydrothermal approach was used to make Zn4O(BDC)3-NiCr2O4 nanocomposite. The structural, morphological and photophysical properties of the prepared samples were used to evaluate various characterization approaches. The Zn4O(BDC)3-NiCr2O4 nanocomposite appears to have a large surface area and increased absorption of visible light. When compared to pure Zn4O(BDC)3 and NiCr2O4, the Zn4O(BDC)3-NiCr2O4 nanocomposite displayed more effective catalytic activity for degradation of methyl orange (MO) and Rhodamine (Rh B) dye from aqueous solution when exposed to visible light. The Zn₄O(BDC)₃-NiCr₂O₄ nanocomposite achieved degradation efficiencies of 93.75 % and 89.91 % for MO and Rh B dyes, respectively, after 210 and 150 minutes of visible light irradiation. The degradation rate for MO was 0.016 min⁻¹, which is approximately 6.66 times and 3.13 times higher than that of pure Zn₄O(BDC)₃ or NiCr₂O₄ nanoparticles, respectively. In addition, the Zn4O(BDC)3-NiCr2O4 nanocomposite showed high structural stability after the degradation test, and most of its photocatalytic activity was retained even after the recycling examination. Moreover, the radical trapping experiments demonstrated that the major active species including superoxide and hydroxyl radicals played main roles in the photocatalytic process. Additionally, the photocatalytic mechanism of Zn4O(BDC)3-NiCr2O4 nanocomposite has been examined, and a more plausible path of hazardous dye degradation has been provided.

Synthesis of nano zero valent zinc-reduced graphene oxide nanocomposite using a novel electrochemical technique for the adsorptive degradation of methyl orange

Indiscriminate disposal of effluent contaminated with persistent azo dyes has become a significant environmental issue. Since the conventional wastewater treatment processes are ineffective in removing azo dyes completely, many studies are currently being focused on finding effective methods to degrade azo dyes. We herein report a novel in-situ synthesis of a nanocomposite with nano-zero valent zinc (nZVZ) and reduced graphene oxide (rGO) that can effectively remove methyl orange, an azo dye, from an aqueous solution via adsorptive degradation. nZVZ-rGO nanocomposite was synthesized by electrochemical reduction of Zn2+ ions on rGO. The presence of nZVZ particles on rGO with an average metal-loading of 4 % was confirmed by SEM-EDS, TEM, XPS and XRD results. Batch experiments showed that a maximum removal efficiency of 99.6 % of methyl orange can be achieved with 25 mg L−1 initial dye concentration and by optimizing the pH, nanocomposite dosage and contact time. However, a noticeable reduction in removal efficiency was observed in the presence of anions such as Cl-, SO42- and CO32-. The degradation of methyl orange was monitored using UV-Visible spectroscopy, HPLC and FTIR spectroscopy. The peaks corresponding to -NN- group, –C-N bond and –SO3Na group have completely disappeared in the product spectrum of FTIR analysis, indicating the degradation of methyl orange. The adsorptive degradation process of methyl orange obeys the Sips model (R2=0.9820) indicating a complex heterogenous adsorption mechanism while the kinetic model was shown to be pseudo-second-order model (R2=0.9999).

Sol–Gel Synthesis of C3N4-Decorated AlFeO3 Photocatalyst and Environmental Purification of Methyl Orange Wastewater

Sol–Gel Synthesis of C3N4-Decorated AlFeO3 Photocatalyst and Environmental Purification of Methyl Orange Wastewater

Synthesis and characterization of AlxCu0.7Mn0.3Fe2-xO4 ferrite and its application in adsorption of dyes

The increasing presence of artificial dyes in industrial wastewater has necessitated the development of efficient and sustainable adsorption materials. This work explores the synthesis and characterization of Al-doped Cu-Mn (AlxCu0.7Mn0.3Fe2-xO4, where x = 0.1, 0.3, 0.5, 0.7, and 0.9) ferrite as a new adsorbent for the removal of dyes from aqueous solutions. The Al-doped Cu-Mn ferrite was prepared using the solution combustion method and meticulously characterized using various physiochemical techniques, including scanning electron microscopy (SEM) analysis, Fourier transform infrared spectroscopy (FTIR), X-ray powder diffractometer (XRD), vibrating sample magnetometer (VSM), and Brunauer-Emmer-Teller (BET). Adsorption studies tested the material's ability to remove hazardous dyes such as congo red, methyl orange, methylene blue, and crystal violet from aqueous solutions. The effects of various parameters, including temperature, contact time, and initial dye concentration, were systematically studied. To understand the mechanism of interaction between the adsorbent and the dyes, the adsorption isotherms were examined using the Langmuir, Temkin, D-R, and Freundlich models. The Freundlich isotherms provided the best fit for the experimental data. To clarify the kinetics of the adsorption process, kinetic experiments were conducted using pseudo-first and pseudo-second-order. According to the results of the kinetics analysis, pseudo-second-order kinetics fit the data better, with a higher coefficient of determination values (R2 = 0.981, 0.983, 0.984 & 0.984). Thermodynamic parameters, including enthalpy, Gibbs free energy, and entropy changes, were calculated to determine the nature of the adsorption process, and the result demonstrates that the adsorption process was endothermic and naturally spontaneous. The results indicate that Al-doped Cu-Mn ferrite exhibits high adsorption capacities and favourable thermodynamic properties, making it a promising material for the removal of dyes from industrial wastewater effluents. The study contributes to the field by providing insights into the adsorption mechanisms and potential applications of Al-doped Cu-Mn ferrite in environmental remediation.

One-pot construction of α-Fe2O3/ZnNiFe2O4 heterojunction by incomplete sol/gel-self-propagating method with choline chloride-ethylene glycol media and its photo-degradation performance

A magnetic α-Fe2O3/ZnNiFe2O4 composite photocatalyst was synthesized through a one-pot reaction employing choline chloride-ethylene glycol deep eutectic solvents and an incomplete sol-gel self-propagating method. The photocatalytic performance was assessed by removing methylene blue (MB) under 40 W visible light. With a 1.0 g/L catalyst dosage, 10 mg/L MB concentration, and pH levels of 6 and 12, removal rates of 97 % and 99 % were achieved within 90 min, respectively. The composite also demonstrated effective degradation of methyl orange (MO) and malachite green (MG). Stability tests revealed minimal reduction in photocatalytic activity after four cycles. Active species analysis identified ·O2⁻ and ·OH as the primary agents in the photocatalytic process. XRD, XPS, UV–VIS DRS, HRTEM, PL, and EIS analyses confirmed the formation of a Z-scheme heterojunction between ZnNiFe2O4 and α-Fe2O3, which enhanced the specific surface area, electron transport capacity, and narrowed the band gap. This heterojunction improved the separation efficiency of photogenerated electron-hole pairs, resulting in enhanced photocatalytic activity and stability. This study presents a novel approach for preparing Z-scheme heterojunction photocatalysts through a one-pot reaction.

Chemical and green synthesized Co/Ni-doped hematite nanoparticles for enhancing the photocatalytic and antioxidant properties

This research focuses on developing environmentally friendly and economically viable Co/Ni-doped hematite nanoparticles (HNPs) through both chemical and green synthesis methods and evaluated their potential for biomedical and environmental applications. The chemical synthesis employs polyvinylpyrrolidone (PVP), while the green approach utilizes Azadirachta indica (A. indica) leaf extract as a stabilizing agent. Co/Ni-doped HNPs are crystalline size ranging from 14 to 21 nm, morphology analysis revealed that the NPs exhibited a quasi-spherical, with an average particle size ranging from 15.98 to 25.91 nm, and dopants confirmed to contain by the XPS spectra. VSM study explains magnetic parameters, coactivity, residual magnetism, and magnetization. A. indica plants contain quinones, saponins, glycosides, alkaloids, and flavonoids. Characterization of the nanoparticles reveals optimized Co/Ni-doped HNPs with enhanced photocatalytic activity. These nanoparticles exhibit a remarkable 93%–95% degradation of UV-reactive dyes (methyl orange and methylene blue) within 90 min, attributed to structural and surface modifications that improve light absorption and enhance charge separation. The study concludes that green-synthesized Co/Ni-doped HNPs outperform chemically synthesized counterparts as superior photocatalysts. Additionally, antioxidant evaluations using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and nitric oxide (NO) assays suggest significant antioxidant capabilities. A high scavenging activity percentage, ranging from 83% to 88%, was observed, which increased with higher concentrations of the synthesized Co/Ni-doped HNPs making these nanoparticles suitable for biomedical and environmental applications that require a magnetic system. In this study, the IC50 values for the antioxidant activity of chemically and green synthesized Co/Ni-doped hematite nanoparticles against the DPPH/NO assay were calculated to be 18.33 μg ml−1 and 16.09 μg ml−1, respectively. The research highlights the multifunctional properties of Co/Ni-doped HNPs, addressing the demand for tailored inorganic magnetic nanoparticles with minimal ecological impact.

Magnetic activated carbon for the removal of methyl orange from water via adsorption and Fenton-like degradation

Water pollution caused by organic dyes is a critical environmental issue. Although activated carbon (AC) is commonly used for dye adsorption, its effectiveness is limited by challenges in separation and regeneration. To address these limitations, a convenient recyclable magnetic activated carbon (MAC) was fabricated via co-precipitation and calcination method, serving as adsorbent and catalyst for methyl orange (MO) removal through a Fenton-like degradation process. Characterization techniques, including XRD, FTIR, SEM and TEM, confirmed that Fe3O4 nanoparticles (10–20 nm) were uniformly dispersed on AC surface. The MAC maintaining a high surface area (997 m2/g) and pore volume (0.795 cm3/g) and exhibited superparamagnetic properties with a saturated magnetization of 5.52 emu/g, enabling effective separation from aqueous solutions by magnet. Batch adsorption studies revealed that MO adsorption onto MAC followed pseudo-second-order kinetic and Freundlich isotherm model, with a maximum adsorption capacity of 205 mg/g at 25 °C. Thermodynamic analysis showed that the adsorption process was spontaneous and endothermic. Simultaneous degradation of MO and in-situ regeneration of MAC were achieved via Fenton-like reaction using sodium persulfate (PS). Under a PS concentration of 9 mmol/L, the MO removal efficiency near 95% after 60 min, with a total organic carbon (TOC) reduction of 83.1%. The reaction of Fe3O4 and oxygen functional groups on AC surface with PS facilitated the generation of SO4•-, thereby enhancing catalytic degradation of MO. The degradation efficiency improved as the temperature increased from 25 °C to 45 °C. Cycle tests demonstrated that the MO removal efficiency of MAC remained above 90% after 5 cycles of regeneration. Overall, this study highlights the potential of MAC for efficient removal of organic dyes from water through the coupling of adsorption and Fenton-like degradation, providing a promising solution for addressing water pollution challenges.

Zeolite-carbon composite synthesis and its adsorption property

In this study, SUZ-4 zeolite-carbon composites were synthesized by a one-step hydrothermal method with solid waste, silica fume (SF), aluminum ash (AA), and chitosan (CS), as raw materials. The composites were analyzed by XRD, SEM, FTIR and BET characterizations. The adsorption capacities of the composites for lead ions (Pb2+) and methyl orange (MO) from aqueous solutions were investigated. Based on the adsorption data, pseudo-second-order model and the Freundlich model were suitable to describe the adsorption process of Pb2+ on the composite, while the pseudo-second-order model and the Langmuir model were preferred to describe the adsorption process of MO on the composite. The maximum adsorption capacity of the composite for Pb2+ was 102.2 mg/g at pH=6, and that for MO was 488.3 mg/g at pH=3. The resulting composites have practical applications as adsorbents for wastewater treatment, thus achieving the goal of “waste for waste”.

Hydrothermal synthesis of BCQD@g-C3N4 nanocomposites supporting environmental sustainability: Organic dye removal and bacterial inactivation

Various studies are being carried out on the removal of organic dyes and the production of antibacterial agents. In this study, boron-doped carbon quantum dot (BCQD) was synthesized by hydrothermal method, and BCQD@g-C3N4 nanocomposite structure was synthesized using graphitic carbon nitride (g-C3N4) as the support material. The photocatalytic activity of the synthesized nanocomposite against MO, RhB dyes, and Escherichia coli (E. coli) bacteria was investigated. The surface, morphology, molecular, and crystal properties of BCQD@g-C3N4 were investigated using characterization methods such as Transmission electron microscopy (TEM), Fourier Transform Infrared Spectroscopy (FTIR), Fluorescence (FL) spectrophotometer, and X-ray diffraction (XRD). As a result of TEM analysis, it was determined that the average particle size of BCQD was 5.1 ± 1.14 nm and showed a homogeneous distribution on 2D g-C3N4. In the XRD spectrum for BCQDs, the diffraction peak corresponding to the (002) amorphous carbon phase was observed at 21.65° In the PL spectrum of B-CQD@g-C3N4s, the emission value was observed at 458 nm. In the study conducted by taking advantage of the photocatalytic feature of BCQD@g-C3N4 nanocomposite, Rhodamine B (RhB) and Methyl orange (MO) were degraded by 65.58 % and 73.56 %, respectively, at the end of 120 min. Additionally, BCQD@g-C3N4 photocatalyst completely inhibited the growth of E. coli bacteria, which are frequently encountered in wastewater, at 90 minutes under sunlight. Escherichia coli (E. coli), which is frequently encountered in wastewater, BCQD@g-C3N4 completely prevented bacterial growth in the 90th minute under sunlight.

Strontium titanate and its flexible polymer composite film: Enhanced biological, mechanical, and photocatalytic performance

Polymeric composite materials are in great demand in biomedical and water treatment applications. This is because they possess distinct characteristics and can fulfill specific biomedical needs, in addition to their ability to degrade dyes. This study successfully synthesized sustainable strontium titanate (STO) particles with an average size of 120 nm using the solid-state method. When these STO particles were mixed into a PCL-based polyurethane matrix, the matrix became hydrophilic with a contact angle of 58.60° and its mechanical strength enhanced by 320%. The morphology and surface roughness of the films were determined using FESEM and AFM techniques. The antibacterial studies of polymeric composites film against E. coli, Klebsiella pneumonia, and S. aureus, showing good zone growth, and showing enhanced swelling properties of 270% for wound healing and biomedical applications. The photocatalytic performance of the STO by degrading Methyl Orange (MO) and Congo Red (CR) under UV light, achieving degradation efficiencies of 92.25% for MO and 62.5% for CR over 150 min. These findings suggest that PU scaffolds and STO are suitable for biological and water treatment in industrial applications.

S-type Bi2S3/BiOBr heterojunction with robust piezo-photocatalytic dye removal activity: Degradation performance and mechanism investigation

In this work, an efficient S-type Bi2S3/BiOBr piezo-photocatalysts was prepared by the decoration of Bi2S3 nanorods on the surface of BiOBr nanosheets. The piezo/photo/piezo-photocatalytic performance of samples were evaluated under the irradiation of ultrasonic and/or simulated-sunlight employing methyl orange (MO) as a target reactant, indicating that above catalytic activity of BiOBr is able to be elevated after Bi2S3 attachment. Particularly, the 10%Bi2S3/BiOBr sample exhibits the optimal catalytic performance. It is worth noting that the 10%Bi2S3/BiOBr sample achieves much higher piezo-photocatalytic MO removal efficiency than its photocatalysis and piezocatalysis, demonstrating a remarkable synergistic improvement between piezocatalysis and photocatalysis with a synergistic enhancement factor (SF) of ∼1.29. The formation of S-type heterojunction in the Bi2S3/BiOBr composite was directly confirmed by the combination of density functional theory (DFT) calculation and in-situ irradiated X-ray photoelectron spectroscopy (ISI-XPS) measurement, elevating the surface separation of generated charges. Meanwhile, the ultrasonic-excited piezoelectric polarization field in BiOBr nanosheets excited by ultrasonic irradiation promotes the bulk segregate of generated charges. Benefiting from above two aspect effects, the overall separation of generated charges can be effectively achieved, leading to outstanding piezo-photocatalytic degradation activity of Bi2S3/BiOBr composite.

Influence of TiO2 Phases and Operational Parameters on Photocatalytic Degradation of Methyl Orange

Influence of TiO2 Phases and Operational Parameters on Photocatalytic Degradation of Methyl Orange

Self-Assembled Nanostructure of Ionic Sn(IV)porphyrin Complex Based on Multivalent Interactions for Photocatalytic Degradation of Water Contaminants.

[Sn(H2PO4)2(TPyHP)](H2PO4)4∙6H2O (2), an ionic tin porphyrin complex, was synthesized from the reaction of [Sn(OH)2TPyP] (1) with a dilute aqueous solution of a polyprotic acid (H3PO4). Complex 2 was fully characterized using various spectroscopic methods, such as X-ray single-crystal crystallography, 1H NMR spectroscopy, elemental analysis, FTIR spectroscopy, UV-vis spectroscopy, emission spectroscopy, EIS mass spectrometry, PXRD, and TGA analysis. The crystal structure of 2 reveals that the intermolecular hydrogen bonds between the peripheral pyridinium groups and the axially coordinated dihydrogen phosphate ligands are the main driving force for the supramolecular assembly. Simultaneously, the overall association of these chains in 2 leads to an open framework with porous channels. The photocatalytic degradation efficiency of methyl orange dye and tetracycline antibiotic by 2 was 83% within 75 min (rate constant = 0.023 min-1) and 75% within 60 min (rate constant = 0.018 min-1), respectively. The self-assembly of 2 resulted in a nanostructure with a huge surface area, elevated thermodynamic stability, interesting surface morphology, and excellent catalytic photodegradation performance for water pollutants, making these porphyrin-based photocatalytic systems promising for wastewater treatment.

Functionalized lignin magnetic composites and their absorption capability for methylene blue and methyl orange in aqueous solution

Functionalized lignin magnetic composites and their absorption capability for methylene blue and methyl orange in aqueous solution

Hyper-Cross-Linked Polyindole for Selective Adsorption and Resource Utilization of Organic Pollutants in Water.

Efficient treatment and utilization of organic pollutants in water are difficult for environmental remediation. A new hyper-cross-linked polymer (PIn-HCP) with high specific surface area was constructed via polyindole (PIn) as building blocks. Rich pore structures and abundant adsorption sites in PIn-HCP were obtained by hyper-cross-linking. The specific surface area of PIn-HCP was enhanced from 14.85 to 431.89 m2/g. The adsorption capacities of PIn-HCP-2 for methylene blue (MB), methyl orange (MO), rhodamine B (RhB), and tetracycline hydrochloride (TH) are 902.0, 275.2, 16.0, and 0.0 mg/g, respectively. PIn-HCP also realized selective adsorption of MB, which can better separate MB/RhB and MB/TH. MB is adsorbed onto PIn-HCP via a synergistic mechanism including π-π stacking, electrostatic interaction, cation-π interaction, hydrogen bonding interaction, and ion exchange. The huge conjugated structure of PIn promotes PIn-HCP to selectively adsorb MB. In addition, PIn-HCP also retains the electrochemical properties of PIn. MB can improve the specific capacitance of PIn-HCP up to five times, and it has potential as a supercapacitor electrode. PIn-HCP offers a promising and practical solution for the efficient treatment and utilization of organic pollutants in water.