In the current study, Rhodamine B (RhB) dye was removed by electro-Fenton (EF) process using iron-doped SBA-15 (Fe-SBA-15; SBA: Santa Barbara Amorphous) mesoporous silica as a heterogeneous catalyst. ...This catalyst was prepared with the help of ferric nitrate nonahydrate as a forerunner by wet impregnation method. Various techniques of characterization such as XRD and N2 adsorption-desorption isotherms were performed to confirm the presence of iron particles in the pores of the catalyst. These characterization methods were also used to examine the morphological properties and textural arrangement of the synthesized material. In the batch study of EF process, 750 mL working volume of RhB dye was taken. Anode and cathode used in the process were graphite electrodes respectively with effective area of 25 cm2 each. To maximise the process efficiency, the effect of initial pH, applied voltage, electrode spacing, the concentration of supporting electrolyte and Fe-SBA-15 dosage were investigated and optimized. The optimum conditions obtained were pH of 2, voltage of 8 V, an electrode spacing of 3 cm and Fe-SBA-15 dosage of 15 mg L−1. At the end of 3 h electrolysis, maximum RhB removal of 97.7% and TOC removal of 35.1% were achieved for 10 mg L−1 RhB concentration. In a batch study with real wastewater, 97% of color and 39% of TOC were removed at optimum conditions. Utilization of EF heterogeneous catalyst Fe-SBA-15 is an alternative technique for the elimination of dyes from solution.
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•Fe-SBA-15 was prepared using wetness impregnation method and was characterized using various techniques.•Effective degradation of rhodamine B dye by Fe-SBA-15 at acidic conditions.•Fe-SBA-15 is a stable heterogeneous EF catalyst.•Heterogeneous EF process is effective than conventional EF process.
The composite hydrogel electrolytes developed from conducting polymers own superb/excellent conductive, self-healing, and mechanical properties. However, it is still challenging to exploit them in ...energy storage devices. To address this issue, novel poly(acrylamide)/poly(3,4-ethylenedioxythiophene): poly(styrene sulfonate) (PEDOT:PSS) composite hydrogel electrolytes were developed through free radical polymerization in which sodium montmorillonite clay was added as a physical crosslinker. The different amounts of PEDOT:PSS were added to the composite hydrogel electrolytes. The structure of the synthesized composite hydrogel electrolytes was investigated by X-ray diffraction (XRD) analysis. The surface morphology of the composite hydrogel electrolyte was examined with the field emission scanning electron microscopy (FESEM) and elemental composition was determined using energy-dispersive X-ray spectroscopy (EDX). The ionic conductivity was measured at ambient temperature. Among the synthesized electrolytes, PEDOTAAM34 achieved the highest ionic conductivity of 13.7 × 10−3 S/cm at room temperature. Furthermore, electrochemical studies were performed by sandwiching the composite hydrogel electrolytes between symmetric carbon-coated graphite electrodes. The fabricated AC/PEDOTAAM34/AC based symmetric supercapacitor attained the highest specific capacitance of 327 F/g at 3 mV/s and 385.4 F/g (energy density of 53.57 Wh/kg at a power density of 100.08 W/kg) at 100 mA/g current density. The self-healable characteristics of symmetric supercapacitors were confirmed by powering up a light-emitting diode (LED).
•Synthesis of novel poly (acrylamide)/(PEDOT: PSS) composite hydrogel electrolytes.•Physical crosslinking enhanced the self-heal ability.•Mixed ionic and electronic conductivity improves the efficiency of supercapacitor.•Self-healable supercapacitor successfully powers up the light emitting diode.
Ternary nanocomposites of polypyrrole (PPy) incorporated with cobalt oxide nanograin (Co3O4), and silver (Ag) nanoparticles were synthesized by hydrothermal methodology and further utilized in ...supercapattery as a positive electrode material. The synthesized ternary nanocomposites (Ag/Co3O4@PPy), as well as their counterparts (Co3O4@PPy and PPy), were analyzed by various analytical techniques such as field emission scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction and X-ray photoelectron spectroscopy. The electrochemical characterizations such as cyclic voltammetry, galvanostatic charge-discharge and electrochemical impedance spectroscopy studies were performed using standard three electrodes cell system in potassium hydroxide (1 M KOH) electrolyte to evaluate the best performing electrode material. Electrochemical studies revealed that the ternary nanocomposites provided much higher specific capacity, low charge transfer and Warburg resistance compared to Co3O4@PPy and pure PPy. The best performing nanocomposite, (Ag/Co3O4@PPy) was used as a positive electrode material for the fabrication of supercapattery which delivered the highest energy density of 24.79 Wh kg−1 and a corresponding power density of 554.40 W kg−1 at a current density of 0.7 A g−1. Moreover, the supercapattery of ternary nanocomposites showed 153.67% of capacity retention even after 3000 cycles. Hence, the synthesized ternary nanocomposites have significant potential to be used in highly stable supercapattery.
Since last decade, momentous development has been made in the biomedical field. However, the contribution of polymer hydrogels as drug delivery carrier cannot be ignored. Crosslinking of natural and ...synthetic polymer has established promising characteristics in stimuli sensitive hydrogels for targeted drug delivery application. In this work, we synthesized N-succinyl chitosan and characterized via Fourier transform infrared (FTIR) spectroscopy, Nuclear magnetic resonance (NMR) spectroscopy, X-ray diffraction (XRD), and differential scanning calorimetry (DSC). Then, we synthesized N-succinyl chitosan-g-Poly (acrylamide-co-acrylic acid) hydrogel via chemical crosslinking of N-succinyl chitosan, acrylamide and acrylic acid. Crosslinking was performed using free radical mechanism. Here, N, N’-methylenebisacrylamide (MBA) and ammonium persulfate (APS) were used as crosslinking agent and initiator, respectively. The hydrogels were synthesized by varying the concentration of monomers, initiator, and crosslinking agent. The chemical interactions in the synthesized hydrogel network were evaluated by FTIR, XRD, and DSC. Field emission scanning electron microscope (FESEM) showed porous morphology of hydrogels. The yield %, gel contents, and gel time were thoroughly examined and excellent results were found. The rheology study was performed to measure the mechanical strength. Moreover, swelling study revealed that hydrogels were highly swellable and depended on the various concentrations of initiator, monomers, and crosslinking agent. The results also showed that pH, type and concentration of salt solutions have strong influence on the swelling properties. Hydrogels expressed reversible swelling behavior in buffer solutions and buffer and salt solutions. Furthermore, theophylline was encapsulated during the synthesis of hydrogel and encapsulation efficiency was found in the range of 59–83%. In addition, theophylline release was observed in buffer solutions of pH 1.2 and pH 7.4. The results revealed the significant effect of pH and hydrogel composition on drug release. The theophylline release was found in the range of 14–24% in buffer solution pH 1.2 and 67–93% in buffer solution pH 7.4. The drug release data showed good fitting to Ritger- Peppas model and release kinetics followed non-Fickian anomalous transport mechanism and relaxation of polymers (case II transport). It was also observed that theophylline maintained its chemical activity after in vitro release. According to the observed facts, synthesized hydrogels can be adapted for their prospective exploitation in targeted drug delivery applications.
In diesel engines, waste cooking oil that obtained from the restaurant has been reused efficiently by mixing alcohols for having it less viscous and dense, despite transesterification or preheating ...to biodiesel. This framework made an attempt to develop an alternate for diesel with Waste cooking oil Methyl Ester (WME) by adding Tyre Pyrolysis Oil (TPO) and Cerium oxide (CeO2) as a reuse fuel. For this objective, five blends are prepared W50T50CeO2100, W60T40CeO2100, W70T30CeO2100, W80T20CeO2100 and W90T10CeO2100 and analyzed regarding the emission and performance characteristics. From the result, it was obvious that this alternate blended fuel that used on the engine at the whole load spectrum has increased greenhouse emission (NOx), whereas attains lesser emission in smoke, CO2, CO and HC emission than diesel. By the addition of these biodiesels i.e. WME with TPO and CeO2, the BTHE poses an improved performance on entire loads yet still maintains lower regarding diesel. Subsequently, the SFC has enhanced performance when compared over diesel fuels. Hence, the harmful emissions and fossil fuel dependence can be reduced effectively by our proposed blended biodiesel fuels, and thereby makes the environment hazards free from contaminating the land and water resources.
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•The machining of magnesium alloy requires attention due to chip ignition risk.•Turning of magnesium alloy is carried out under dry and MQL cutting conditions.•This study uses Taguchi ...based GRA technique for choosing optimal cutting parameters.•Feed rate is the most dominant factor for the multi-objective characteristics.
Recent research in the field of magnesium has brought out the enormous potential in terms of their applications and machining process. Lightness and high strength-to-weight ratio of such materials have led to an increased interest in their use in automobile and aerospace industries. In this paper investigation on turning of magnesium alloy using uncoated tungsten carbide cutting insert in dry and minimum quantity lubrication (MQL) cutting conditions have been presented. This work includes input parameters like cutting conditions, cutting speed, feed and depth of cut as cutting factors and the responses of tool flank wear, surface roughness, cutting force and cutting temperature have been optimized by grey relational analysis. The optimization has been performed firstly as mono-objective optimization by using Taguchi method; secondly as multi-objective optimization through Taguchi based grey relational analysis (GRA). The mono-objective optimization results gave the combination of 40 m/min cutting speed, 0.10 mm/rev feed rate and 0.5 depth of cut when run under MQL for optimizing the tool wear and cutting temperature and also the same combination optimized cutting force when operated under dry condition. The optimal condition for surface roughness was at 140 m/min cutting speed, 0.10 mm/rev feed rate, 0.5 depth of cut at MQL. GRA technique provided optimum condition i.e. 90 m/min cutting speed, 0.1 mm/rev feed rate and 0.5 mm depth of cut at MQL that minimized the output responses.
The research work was conducted to synthesize transparent self-cleaning coatings by using organic Polydimethylsiloxane (PDMS) polymers and inorganic nano-Calcium carbonate (CaCO3) fillers that can be ...fabricated easily on the glass panel via spray-method and cured under room temperature. The coating system has been developed with a low-cost nano-CaCO3 and simple process which is targeted to keep the cost at lower side. The self-cleaning and durability of nano-CaCO3 coating systems after 4 month of outdoor exposure have been investigated. From the obtained result, the transmission of 0.8 wt % of nano-CaCO3 coated substrate was slightly degraded by 7% only indicating that its excellent self-cleaning effect. Higher loading ratio of nano-CaCO3 contributes to larger capillary pressure (Pc) and air-pockets which have deteriorated the water hammer pressure of rainfall impact (PWH) and fog. Therefore, the Water Contact Angle (WCA) of coating system was degraded by 2% only and exhibits a great anti-fog property.
•A facile method to prepare self-cleaning coating that cured at room temperature.•High transparency nano-Calcium Carbonate coatings approximately 90% in UV–Vis region.•Only 7% of transparency loss for coated glass after 4 month of outdoor exposure.•Only 1.57%–2.20% of hydrophobic loss for coated glasses after 4 month.•A great anti-fog property of coated glass plates under extended fog exposure.
A dye-sensitized solar cell (DSSC) is the alternative photovoltaic technology for the replacement of the standard photovoltaic liquid electrolyte-dependent cell. Gel polymer electrolyte (GPE) was ...used in this research to replace the volatile liquid electrolyte. This GPE has been developed using terpolymer type Poly(vinyl butyral-co-vinyl alcohol-co-vinyl acetate) P(VB-co-VA-co-VAc), iodine (I2), sodium iodide (NaI), and ethanol. The findings from X-ray diffraction (XRD) showed the effect of NaI on the crystalline content of the electrolyte systems. Samples showed higher conductivity with a lower degree of crystallinity. Differential scanning calorimetry (DSC) analysis revealed the slight decrease in melting temperature (Tm) upon addition of NaI salts. The thermogravimetric analysis (TGA) showed that GPE ′s thermal stability decreases as NaI salt content increases. Fourier-transform infrared (FTIR) results indicated that P(VB-co-VA-co-VAc) interacted with NaI. The highest room temperature ionic conductivity of 3.22 × 10−3 S cm−1 by the sample with 30 wt % NaI. Temperature-dependent findings showed that all GPE samples adhere to the Arrhenius equation in the temperature range from 303 K to 373K and found the lowest activation energy obtained by the sample with 30 wt % NaI as 0.066 eV. Dielectric and modulus properties of all samples have been studied. DSSC fabricated using the electrolyte containing 30 wt% NaI has achieved the highest conversion efficiency of 4.01% with maximum JSC value of 12.52 mA cm−2, VOC of 0.61 V, and fill factor (FF) of 51.8%.
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•Efficiency enhancement in a DSSC with terpolymer type and NaI salt is reported.•Incorporation of NaI improves the properties and performance of P(VB-co-VA-co-VAc) GPEs.•Improvement in Dapp value of I3− based GPE by the increased NaI content.•30 NaI:70 P(VB-co-VA-co-VAc) (wt.%) mixture produced maximum JSC and 4.01% efficiency.
Gel polymer electrolytes using imidazolium based ionic liquids have attracted much attention in dye-sensitized solar cell applications. Hydroxypropyl cellulose (HPC), sodium iodide (NaI), ...1-methyl-3-propylimidazolium iodide (MPII) as ionic liquid (IL), ethylene carbonate (EC) and propylene carbonate (PC) are used for preparation of non-volatile gel polymer electrolyte (GPE) system (HPC:EC:PC:NaI:MPII) for dye-sensitized solar cell (DSSC) applications. The highest ionic conductivity of 7.37 × 10(-3) S cm(-1) is achieved after introducing 100% of MPII with respect to the weight of HPC. Temperature-dependent ionic conductivity of gel polymer electrolytes is studied in this work. XRD patterns of gel polymer electrolytes are studied to confirm complexation between HPC polymer, NaI and MPII. Thermal behavior of the GPEs is studied using simultaneous thermal analyzer (STA) and differential scanning calorimetry (DSC). DSSCs are fabricated using gel polymer electrolytes and J-V centeracteristics of fabricated dye sensitized solar cells were analyzed. The gel polymer electrolyte with 100 wt.% of MPII ionic liquid shows the best performance and energy conversion efficiency of 5.79%, with short-circuit current density, open-circuit voltage and fill factor of 13.73 mA cm(-2), 610 mV and 69.1%, respectively.
A random poly(methyl methacrylate-co-butyl acrylate-co-acrylic acid) P(MMA-co-BA-co-AA) was synthesized via emulsion polymerization utilizing thermally-activated persulfate radicals. The successful ...synthesis of high molecular weight copolymer at high monomer conversion rate was confirmed by NMR study. Various techniques were employed to characterize the structure, electrical and thermal properties of copolymer. The removal of unreacted monomers from the end product by casting technique was rationalized from the disappearance of CC FTIR characteristic peak in the cast film. The drying of the emulsion above the glass transition temperature (Tg=24°C) yields an amorphous film with smooth surface morphology. The suitability of the formed continuous film as a base polymer for iodide-based electrolytes in dye sensitized solar cell (DSSC) fabrication was investigated. The polymeric solid state electrolytes (PSSE) were formulated by varying the doping concentrations of sodium iodide (NaI) in fixed ratio of iodine (I2) and mixtures of ethylene carbonate: propylene carbonate (EC:PC, 1:1). The DSSC fabricated using PSSE with 15wt.% NaI showed the highest solar-to-electrical energy conversion efficiency (η) of 3.22% under 100mWcm−2 sunlight intensity. This implies that the physico-chemical properties of the synthesized copolymer are suitable for the development of photoelectrochemical device.
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•We have synthesised ultra-high molecular weight copolymer based on acrylates.•Highest conversion efficiency of 3.22% at 1 Sun, and prolonged durability is attained.•It is not always true that copolymer with large molecular weight will obstruct electrochemical function.
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