Facile Reflux Method Research Articles

Facile Synthesis Method of Zeolite NaY and Zeolite NaY-Supported Ni Catalyst with High Catalytic Activity for the Conversion of CO2 to CH4

In this work, the facile reflux method was used as a crystallization procedure for zeolite NaY synthesis. The zeolite mixture was aged for 7 days and then refluxed for crystallization at 100 °C for 12 h. The synthesized zeolite NaY was impregnated with 10, 20 and 30 wt%Ni solution to use as a catalyst for CO2 methanation. The 30 wt% of Ni on the zeolite NaY catalyst showed the highest CO2 methanation catalytic activity, with almost 100% CH4 selectivity. This can be explained by an appropriate H2 and CO2 adsorption amount on a catalyst surface being able to facilitate the surface reaction between them and further react to form products. The oxidation state of Ni and the stability of the catalyst were monitored by time-resolved X-ray absorption spectroscopy. The oxidation state of Ni2+ was reduced during the catalyst reduction prior to the CO2 methanation and it was completely reduced to Ni° at 600 °C. During CO2 methanation, Ni° remained unchanged. In addition, the stability test of the catalyst was conducted by exposing the catalyst to a fluctuating condition (CO2 + H2 and only CO2). The oxidation state of Ni° remained unchanged under the fluctuating condition. This indicated that the Ni/zeolite catalyst has high stability, which can be attributed to an appropriate binding strength between Ni and the zeolite support.

A facile reflux method to produce ternary CQDs/P25/NH2−MIL-125 for photocatalytic degradation of methylene blue under simulated solar light

BackgroundTo enhance the photocatalytic performance of commercial titanium dioxide (P25), carbon quantum dots (CQDs) and NH2−MIL-125 were utilized to address its limitations arising from the large bandgap and small specific surface area. The CQDs were employed to broaden the range of solar light absorption, while NH2−MIL-125 was used to disperse P25 with a higher specific surface area. MethodsA facile reflux method was conducted to synthesize CQD/P25/NH2−MIL-125 composite materials. The up-conversion photoluminescence (UCPL) effect of CODs was leveraged to convert longer wavelengths of light into shorter ones, facilitating P25 and NH2−MIL-125 to enhance photocatalytic performance. Significant findingsThe UCPL effect of CQDs not only broadened the light absorption range but also retarded the recombination of photo-induced electron-hole pairs, leading to improved photocatalytic reactions. Furthermore, the effect of additional amounts of CQDs was investigated, and it was found that 1wt% CQDs/P25/NH2−MIL-125 followed first-order kinetics, with the highest rate constant (k1) of 0.0141.

Cubic AgBiS2 Powder Prepared Using a Facile Reflux Method for Photocatalytic Degradation of Dyes.

The ternary chalcogenide AgBiS2 has attracted widespread attention in the field of photovoltaic and photoelectric devices due to its excellent properties. In this study, AgBiS2 powders with an average diameter of 200 nm were prepared via a simple and convenient reflux method from silver acetate, bismuth nitrate pentahydrate, and n-dodecyl mercaptan. The adjustment of the ratios of Ag:Bi:S raw materials and of the reaction temperatures were carried out to investigate the significance of the synthesis conditions toward the composition of the as-synthesized AgBiS2. The results of XRD indicated that the powders synthesized at a ratio of 1.05:1:2.1 and a synthesis temperature of 225 °C have the lowest bismuth content and the highest purity. The synthesized AgBiS2 crystallizes in a rock salt type structure with the cubic Fm3¯m space group. Scanning and transmission electron microscopy, thermogravimetric analysis, ultraviolet-visible-near-infrared spectra, and photocatalytic degradation performance were employed to characterize the as-synthesized samples. The results demonstrated that AgBiS2 powders display thermal stability; strong absorption in the ultraviolet, visible, and partial infrared regions; and an optical bandgap of 0.98 eV. The obtained AgBiS2 powders also have a good degradation effect on the methylene blue solution with a degradation efficiency of 58.61% and a rate constant of 0.0034 min-1, indicating that it is an efficient strategy for sewage degradation to reduce water pollution.

Fabricating polyacrylonitrile-polyethyleneimine nanofiber membranes with exceptional hemocompatibility and efficient bilirubin removal for hemoperfusion

Bilirubin, a severe endogenous toxin, underscores the critical need for the development of bilirubin adsorbents exhibiting both high removal efficiency and exceptional hemocompatibility. Such advancements are pivotal for augmenting the efficacy of hemoperfusion therapy in managing hyperbilirubinemia. Here, a polyacrylonitrile-polyethyleneimine (PAN-PEI) nanofiber membrane (NFM) with elevated amino content was prepared using a facile reflux method for bilirubin adsorption. The PAN-PEI NFMs exhibited a significantly augmented surface amino density of 23.5 mmol.m−2, consequently achieving a remarkable bilirubin adsorption capacity of 87.65 mg.g−1, along with an impressive removal efficiency of 92.3% for bilirubin. Additionally, these nanofiber membranes displayed excellent hemocompatibility, including minimal hemolysis rates, significant anti-protein and anti-hemocyte adhesion properties, as well as a certain degree of anticoagulant activity. These results indicate that the vast potential of using PAN-PEI nanofiber membranes for hyperbilirubinemia hemoperfusion therapy.

CuO/ZnO Type-II heterojunction modified by rGO nanosheets for improved photocatalytic mineralization of antibiotics

In the present work, CuO/ZnO type-II heterojunction was modified by graphene oxide nanosheets for excellent photocatalytic mineralization of antibiotics under artificial UV light and natural sunlight. For this purpose, CuO/ZnO heterojunction-graphene oxide nanocomposites were synthesized via a facile refluxing method in aqueous media. The synthesized nanocomposites were characterized through diverse characterization techniques such as XRD, FT- IR, Raman, SEM, TEM, and UV–Vis DRS to determine their structural, morphological, and optical properties. XRD analysis confirmed the monoclinic CuO and hexagonal wurtzite ZnO phase in bare CuO/ZnO heterojunction and different CuO/ZnO heterojunction-graphene oxide nanocomposites as well. The optical band gap was found in the range of 3.06–3.19 eV for different nanocomposites. The photocatalytic activity of the bare heterojunction and nanocomposites was performed against the degradation of ciprofloxacin under the irradiation of artificial UV and natural sunlight as well. The highest degradation % of ciprofloxacin was achieved at 96.27 % and 76.44 % under artificial UV and natural sunlight within 120 min, respectively over CuO/ZnO heterojunction with 3 wt% of graphene oxide. The outstanding photocatalytic performance of CuO/ZnO heterojunction-graphene oxide (3 wt%) owing to the high adsorption capacity and synergism between CuO/ZnO and graphene oxide caused the improved separation of charge species resulting higher production rate of reactive oxygen species and prompt degradation of ciprofloxacin.

Ni(OH)2 Derived from NiS2 Induced by Reflux Playing Three Roles for Hydrogen/Oxygen Evolution Reaction

Developing efficient and promising non-noble catalysts for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) is vital but still a huge challenge for the clean energy system. Herein, we have integrated the active components for OER (Ni(OH)2) and HER (NiS2 and Ni(OH)2) into Ni(OH)2@NiS2 heterostructures by a facile reflux method. The in-situ formed Ni(OH)2 thin layer is coated on the surface of hollow NiS2 nanosphere. The uniform Ni(OH)2@NiS2 hollow sphere processes enlarge the electrochemically active specific surface area and enhance the intrinsic activity compared to NiS2 precursor, which affords a current density of 10 mA cm−2 at the overpotential of 309 mV and 100 mA cm−2 at 359 mV for OER. Meanwhile, Ni(OH)2@NiS2 can reach 10 mA cm−2 at 233 mV for HER, superior to pure NiS2. The enhanced performance can be attributed to the synergy between Ni(OH)2 and NiS2. Specifically, Ni(OH)2 has three functions for water splitting: providing active sites for hydrogen adsorption and hydroxyl group desorption and working as real OER active sites. Moreover, Ni(OH)2@NiS2 displays great stability for OER (50 h) and HER (30 h).

Boosting Magnesium Ion Storage Behavior via Heteroelement Doping in a Porous Tunnel Framework Cathode for Aqueous Mg-Ion Batteries.

To relieve the overwhelming pressure on fossil energy, aqueous magnesium ion batteries attracted tremendous attention owing to their low cost and high safety. However, the cathode materials are apt to occur lattice distortion because of the electrostatic interaction between magnesium ions and crystal. The 2×2 manganese octahedral molecular sieve with potassium ions and water located in the tunnels (K-OMS-2), utilized as a cathode material for chargeable magnesium ions batteries, is exposed to irreversible Mg2+ intercalation/deintercalation due to lattice distortion, which heavily damages the electrochemical properties and declines the capacity. Herein, we carry out an ion doping strategy to overcome the above issues, leading to an enhanced Mg Mg2+ storage behavior. The Nb or V cation is successfully doped into K-OMS-2 by a facile reflux method under room temperature. The specific surface area is enlarged by the addition of cations, which promise a large electrode-electrolyte contact area. The Nb and V doped K-OMS-2 present a capacity of 252.6 and 265.9 mAh/g at 20 mA/g, respectively. This work demonstrates an ion doping approach toward exploiting the stable and high-capacity Mg-ion battery cathode and provides potential cathode materials for a large-scale aqueous Mg-ion-based energy storage system.

Nanoarchitecture of a Ti3C2@TiO2 Hybrid for Photocatalytic Antibiotic Degradation and Hydrogen Evolution: Stability, Kinetics, and Mechanistic Insights.

Designing of a visible-light-driven semiconductor-based heterojunction with suitable band alignment and well-defined interfacial contact is considered to be an effective strategy for the transformation of solar-to-chemical energy and environmental remediation. In this context, MXenes have received tremendous attention in the research community due to their merits of abundant derivatives, elemental composition, excellent metallic conductivity, and surface termination groups. Meanwhile, a facile synthetic strategy for MXene-derived TiO2 nanocomposites with stable framework and higher photocatalytic activity under visible-light irradiation still remains a challenge for researchers. Herein, we report a novel synthetic strategy of preparing a two-dimensional Ti3C2@TiO2 nanohybrid by a facile reflux method under acidic conditions. In this oxidation reaction, protonation of the hydroxyl terminal group of MXene creates Ti more electrophilic and susceptible to an oxidative nucleophilic addition reaction with the presence of both water and oxygen. The physicochemical properties of the nanohybrid Ti3C2@TiO2 were verified by varieties of characterization techniques. High-resolution transmission electron microscopy and X-ray photoelectron spectroscopy analysis specifically elucidated the intimate interfacial interaction between Ti3C2 and TiO2. The optimized Ti3C2@TiO2-48 h photocatalyst exhibited the highest tetracycline hydrochloride (TCH, 90% in 90 min) degradation efficiency in comparison to pristine TiO2 with a rate constant (k) of 0.02463 min-1. The major contribution of •O2- and •OH radicals throughout photocatalytic TCH degradation was confirmed by the trapping experiment. Moreover, the photocatalyst showed the highest hydrogen generation rate of 140.8 μmol h-1 along with an apparent conversion efficiency of 2.2%. The excellent photocatalytic activity of Ti3C2@TiO2 originated from the superior electrical conductivity of cocatalyst Ti3C2, which facilitated spatial photogenerated e-/h+ separation and transfer at the Ti3C2 MXene@TiO2 interface. Overall, this research work will describe a promising protocol of designing MXene-derived photocatalysts toward efficient environmental remediation and wastewater treatment applications.

A p-n Junction by Coupling Amine-Enriched Brookite-TiO2 Nanorods with CuxS Nanoparticles for Improved Photocatalytic CO2 Reduction.

Photocatalytic CO2 reduction is a promising technology for reaching the aim of "carbon peaking and carbon neutrality", and it is crucial to design efficient photocatalysts with a rational surface and interface tailoring. Considering that amine modification on the surface of the photocatalyst could offer a favorable impact on the adsorption and activation of CO2, in this work, amine-modified brookite TiO2 nanorods (NH2-B-TiO2) coupled with CuxS (NH2-B-TiO2-CuxS) were effectively fabricated via a facile refluxing method. The formation of a p-n junction at the interface between the NH2-B-TiO2 and the CuxS could facilitate the separation and transfer of photogenerated carriers. Consequently, under light irradiation for 4 h, when the CuxS content is 16%, the maximum performance for conversion of CO2 to CH4 reaches at a rate of 3.34 μmol g-1 h-1 in the NH2-B-TiO2-CuxS composite, which is approximately 4 times greater than that of pure NH2-B-TiO2. It is hoped that this work could deliver an approach to construct an amine-enriched p-n junction for efficient CO2 photoreduction.

RGO supported ZnO/SnO2 Z-scheme heterojunctions with enriched ROS production towards enhanced photocatalytic mineralization of phenolic compounds and antibiotics at low temperature

In the present study, the excellent photocatalytic activity of n-ZnO/n-SnO2 heterojunction integrated with reduced graphene oxide nanosheets was explored towards the elimination of different organic pollutants viz. p-bromophenol, bisphenol A, and ofloxacin from water. n-ZnO/n-SnO2 heterojunction was decorated with a different weight percentage of reduced graphene oxide via a facile refluxing method. The structural, morphological and optical properties of the as-prepared n-ZnO/n-SnO2 heterojunction-reduced graphene oxide nanocomposites were investigated systematically. XRD, Raman and FT-IR confirmed the hexagonal wurtzite and tetragonal rutile structures of ZnO and SnO2 crystals in different nanocomposites. Cube and spherical-shaped surface structures were demonstrated by TEM and FE-SEM analysis for ZnO and SnO2, respectively. The maximum photocatalytic productivity of nanocomposite with 5 wt% reduced graphene oxide was observed at about 98.64 % and 98.50 % towards the elimination of p-bromophenol and bisphenol A, respectively after 180 min exposure of UV light. Similarly, this productivity was also observed at about 99.13 % towards the elimination of ofloxacin after 120 min irradiation of UV light. The outstanding photocatalytic activity of nanocomposite with 5 wt% reduced graphene oxide has been proven by the presence of homotypic n-ZnO/n-SnO2 and reduced graphene oxide nanosheets owing to the synergistic effect amongst them resulting in remarkable separation of charge carriers, which is responsible for the larger rate of reactive oxygen species generation and enhanced photodegradation of p-bromophenol, bisphenol A and ofloxacin. In this study, the results illustrated that the photocatalytic degradation of p-bromophenol, bisphenol A and ofloxacin using n-ZnO/n-SnO2 heterojunction-reduced graphene oxide nanocomposites is predominantly based on the hydroxyl radicals and superoxide radical anion as main reactive oxygen species as compared to 1O2. A reasonable photodegradation mechanism using prepared nanocomposites under investigation has also been proposed.

Flower-like nickel‑cobalt-layered double hydroxide nanosheets deposited on hierarchically porous graphitic carbon nitride for enhanced electrochemical energy storage

Herein, flower-like nickel‑cobalt-layered double hydroxide nanosheets (f-NiCo-LDH) were deposited on porous graphitic carbon nitride (g-CN) by using F127 as the structure modulating agent and through a facile refluxing method. Benefiting from the binary composition and hierarchically porous structure, the optimized f-NiCo-LDH/g-CN2 composite delivered high specific capacitance of 2933.3 F g−1 at 0.5 A g−1, high rate capability of 410 F g−1 at 50 A g−1, and stable cycling behavior with 75.3% capacitance retention after 7000 cycles. When the f-NiCo-LDH/g-CN2 composite was assembled as cathode in asymmetric capacitor with activated carbon as the anode, the hybrid supercapacitor could deliver a maximum energy density of 52.7 Wh kg−1 at the current of 0.5 A g−1. Therefore, the superior capacitive properties as well as the simple preparation strategy of the as-prepared f-NiCo-LDH/g-CN2 material indicate its promising application as high-performance electrode for supercapacitors.

Synthesis of metal organic framework modified with carboxylated attapulgite and adsorption properties for organic dye

PurposeThe purpose of this study was to prepare carboxylated attapulgite (APT-COOH) and then be used as one of the ligands to prepare metal organic framework (MOF) hybrid materials to reduce the cost of MOF materials and improve the dispersed condition of APT. And then the materials were used to enrich anionic dye Congo red from aqueous solution.Design/methodology/approachThe MOF hybrid materials were designed by means of facile reflux method rather than hydrothermal method, characterized by Thermogravimetric Analysis (TGA), Fourier Transform Infrared (FTIR) Spectrometer and pore structure. The dispersed degree of APT-COOH in the MOF materials was validated according to adsorption efficiency for Congo red.FindingsDue to introduction of APT-COOH, the microenvironment of the MOF materials changed, leading to different adsorption behaviors. Compared to the MOF material without APT-COOH, the adsorption capacities of the hybridized MOF materials with different amounts of APT-COOH introduced increased by 4.58% and 15.55%, respectively, as the initial concentration of Congo red solution of 300 mg/L. Meantime, hybridized MOF materials were suitable to remove Congo red with low concentration, while the MOF material without APT-COOH was appropriate to enrich Congo red with high concentration.Research limitations/implicationsThe microstructure of MOF hybrid materials in detail is the further and future investigation.Practical implicationsThis study will provide a method to reduce the cost of MOF materials and a theoretical support to treat anionic dyes from aqueous solution.Originality/valueAPT-COOH was prepared and used as one of the ligands to synthesize MOF material to improve the dispersed degree of APT-COOH and reduce the cost of the MOF materials. The adsorption efficiency was greatly enhanced with low concentration of Congo red solution, and the results indicated that hydrogen bonding, electrostatic interaction, and p-p conjugation were involved in the adsorption process. The prepared MOFs materials exhibited excellent adsorption efficiency, which made the present materials highly promising and potentially useful in practical application as adsorbents to enrich anionic dyes such as Congo red from aqueous solution.

A Facile Approach for the Synthesis of SrTiO3/g‐C3N4 Photo‐catalyst and its Efficacy in Biodiesel Production

AbstractVisible light active photocatalysts have attracted a lot of interest due to their simple chemical workup and recyclability. In this study, the role of Strontium Titanate/graphitic Carbon Nitride composite (SrTiO3/g‐C3N4) was investigated for the pretreatment of waste frying oil (WFO) to reduce high free fatty acids (FFAs) for biodiesel production. SrTiO3/g‐C3N4 photo‐catalyst was synthesized through the facile refluxing method and its activity was also compared with simple graphitic carbon nitride (g‐C3N4). Experimental results revealed that SrTiO3/g‐C3N4 possesses higher efficiency as compared to g‐C3N4. Photo‐catalyst was characterized through SEM‐EDX, XRD and FT‐IR. Maximum conversion of FFAs (85 %) was achieved at 1 % catalyst dose, 800 rpm stirring speed, 3 : 1 methanol to oil ratio, and 4 hours of reaction time. Esterified WFO was converted to waste frying oil methyl esters (WFOME) by using CaO‐KOH heterogeneous catalyst. The maximum yield of WFOME was obtained at 1.25 % catalyst dose, 65 °C, 600 rpm, 2 h of reaction time, and 12 : 1 methanol to oil ratio. Physicochemical analysis of WFOME revealed that it is in accord with ASTM standards.

Facile preparation of Porous aromatic frameworks PAF-56 membranes for nanofiltration of dyes solutions

Porous aromatic frameworks (PAFs), possessing a high specific surface area, inherent porosity, nanosized channels and diverse structure, exhibit extraordinary potential in various fields. Herein, PAF-56 membranes were in situ fabricated on modified polyvinylidene fluoride (PVDF) membranes by a mild and facile refluxing method (62 ℃) and applied in nanofiltration. The influence of reaction time, reactant concentrations and catalyst concentration on the PAF-56/PVDF membranes were explored. The PAF-56/PVDF membranes showed a remarkable rejection (>95.08 %) and permeability (>40 L m-2h−1 bar−1) for dyes (Mw > 319) solutions. The membrane also exhibited excellent reusability and chemical stability, indicating great potential for actual separations.

Fabrication of MIL-53(Al)/Ag/AgCl plasmonic nanocomposite: An improved metal organic framework based photocatalyst for degradation of some organic pollutants

Metal organic framework (MOF) based MIL-53(Al)/Ag/AgCl nanocomposite (NC) was synthesized as a novel plasmonic photocatalyst via a facile reflux method. The as-prepared NC was characterized by various techniques. The photocatalytic efficiency of MIL-53(Al)/Ag/AgCl was investigated by photo-degradation of six cationic and anionic dyes. The effect of different factors including weight ratio of NCs, illumination time, and initial dye concentration on the photocatalytic performance of MIL-53(Al)/Ag/AgCl were experimentally investigated. The MIL-53(Al)/Ag/AgCl(10%) exhibited the highest catalytic performance for photo-degradation of different dye contaminants. Results indicated about 80–100% of tested dyes were removed by MIL-53(Al)/Ag/AgCl under LED-light irradiation in 90 ​min. Because of heterojunction between the Ag/AgCl nanoparticles (NPs) and MIL-53(Al), the MIL-53(Al)/Ag/AgCl NC showed higher photocatalytic ability. The results confirmed that due to some considerable features of MIL-53(Al)/Ag/AgCl such as high surface area, surface plasmon resonance effect, and recyclability, the introduced NC acts as a high performance photocatalyst for degradation of dyes in aqueous solutions.

A high sensitive and selective fluorescent probe for dopamine detection based on water soluble AgInS2 quantum dots

Herein, a water soluble AgInS2 quantum dots (AIS QDs) with high sensitive and selective for dopamine (DA) were prepared through a clean and facile reflux method with the mercapto propionic acid (MPA) and polyethyleneimine (PEI) used as the co-modifiers. The fluorescence quench of as-fabricated AIS QDs displayed an excellent selectivity and sensitivity to the DA and they showed a good linear relationship with the low detection limit (2.84 nm) in the range of 0.5–300 μmol/L. The mechanism of fluorescence quench may attributed to the photoinduced electrons migrated from AIS QDs to dopamine quinone, which originated from the oxidization of DA by ambient O2. Our work shows a promising prospect of designing and preparing AIS QDs used as the fluorescence sensors for DA detection.

MOFs-Derived Porous NiFe2O4 Nano-Octahedrons with Hollow Interiors for an Excellent Toluene Gas Sensor.

Toluene is extensively used in many industrial products, which needs to be effectively detected by sensitive gas sensors even at low-ppm-level concentrations. Here, NiFe2O4 nano-octahedrons were calcinated from NiFe-bimetallic metal-organic framework (MOFs) octahedrons synthesized by a facile refluxing method. The co-existence of p-Phthalic acid (PTA) and 3,3-diaminobenzidine (DAB) promotes the formation of smooth NiFe-bimetallic MOFs octahedrons. After subsequent thermal treatment, a big weight loss (about 85%) transformed NiFe2O4 nanoparticles (30 nm) into NiFe2O4 porous nano-octahedrons with hollow interiors. The NiFe2O4 nano-octahedron based sensor exhibited excellent gas sensing properties for toluene with a nice stability, fast response, and recovery time (25 s/40 s to 100 ppm toluene), and a lower detection limitation (1 ppm) at 260 °C. The excellent toluene-sensing properties can not only be derived from the hollow interiors combined with porous nano-octahedrons to favor the diffusion of gas molecules, but also from the efficient catalytic activity of NiFe2O4 nanoparticles.

Constructing a Z-scheme Heterojunction of Egg-Like Core@shell CdS@TiO₂ Photocatalyst via a Facile Reflux Method for Enhanced Photocatalytic Performance.

A well designed and accurate method of control of different shell thickness and electronic transmission in a Z-scheme core@shell system is conducive to obtaining an optimum photocatalytic performance. Herein, the Z-scheme heterojunction of egg-like core@shell CdS@TiO2photocatalysts with controlled shell thickness (13 nm, 15 nm, 17 nm, 22 nm) were synthesized by a facile reflux method, and the CdS@TiO2 structure was proved by a series of characterizations. The photodegradation ratio on methylene blue and tetracycline hydrochloride over the 0.10CdS@TiO2 composites with TiO2 shell thickness of 17 nm reached 90% in 250 min and 91% in 5 min, respectively, which was almost 9.8 times and 2.6 times than that of TiO2 and CdS on rhodamine B respectively under visible light. Besides, the higher total organic carbon removal ratio indicated that most of the pollutants were degraded to CO2 and H2O. The Z-scheme electronic transfer pathway was studied through radical species trapping experiments and electron spin resonance spectroscopy. Moreover, the relationship between shell thickness and photocatalytic activity demonstrated that different shell thickness affects the separation of the electron and holes, and therefore affected the photocatalytic performance. In addition, the effects of pollutants concentration, pH, and inorganic anions on photocatalytic performance were also investigated. This work can provide a novel idea for a well designed Z-scheme heterojunction of core@shell photocatalysts, and the study of photocatalytic performance under different factors has guiding significance for the treatment of actual wastewater.

Exceptional photocatalytic activity for g-C3N4 activated by H2O2 and integrated with Bi2S3 and Fe3O4 nanoparticles for removal of organic and inorganic pollutants

Herein, hydrogen peroxide activated graphitic carbon nitride (agCN) was combined with Fe3O4 and Bi2S3 to fabricate agCN/Fe3O4/Bi2S3 nanocomposites via facile refluxing method, as visible-light-induced photocatalysts for photodegradations of anionic and cationic dyes such as MO, RhB, MB, and photoreduction of Cr(VI). The fabricated samples were explored by XRD, EDX, XPS, TGA, SEM, TEM, HRTEM, VSM, PL, FT-IR, BET, and UV-vis DRS. Photocatalytic activity of the nanocomposite with 20% of Bi2S3 was 16.6, 40.4, 19.5, and 12.5 times more than that of the pristine gCN in removal of RhB, MB, MO, and Cr(VI), respectively. A plausible photocatalytic mechanism on the agCN/Fe3O4/Bi2S3 nanocomposites was proposed by construction of n-n heterojunction between gCN and Bi2S3. Also, stability of the magnetic hybrid was characterized through cyclic photocatalytic tests.

Synergistic Enhancement in Antibacterial Activity of Core/Shell/Shell SiO2/ZnO/Ag3PO4 Nanoparticles

AbstractNovel core/shell/shell SiO2/ZnO/Ag3PO4 nanoparticles (SZA‐NPs) were prepared through a facile reflux method involving sequential deposition of ZnO and Ag3PO4 to SiO2 spheres. The obtained SZA‐NPs were systematically characterized and used as the dual‐functional antibacterial agents for disinfection. Under visible‐light irradiation, the SZA‐NPs exhibit enhanced antibacterial activity for of Escherichia coli DH5α (E. coli) compared to that of Ag3PO4 or SiO2/ZnO in liquid phase and on agar plates. Quantitative analysis of Ag+ release from SZA‐NPs confirms the minor contribution of released silver ions to the antibacterial efficiency. On the other hand, chemical scavengers and photoluminescence studies suggest that radical oxygen species (ROS) also make major contribution to E. coli cell death. The enhanced antibacterial activity of the SZA‐NPs under visible‐light irradiation can be attributed to the synergistic effect of released silver ions and ROS generated from the excellent band matching between Ag3PO4 and ZnO. This work paves a new way for future design of highly efficient visible‐light induced antibacterial agents.