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Nanoparticles of tungsten oxide are widely used in advanced chemical processes but the application of tungsten oxide (WO3) in photocatalysis is limited. To increase their application in photocatalysis, nanostructured tungsten oxide (W-1) is co-doped with silver and copper (W-2), and nanocomposites with g-C3N4 (W-3) and CNTs (W-4) are synthesized. Structural, elemental, and morphological analyses of prepared samples were carried out using different characterization techniques like XRD, SEM, FTIR, EDX, and Mott-Schottky. The bandgap of WO3 is 2.75 eV which is reduced to 2.32 eV by doping and composite formation. The degradation of crystal violet and chlorpyrifos is done to check the photocatalytic performance of prepared materials under the light bulb energy. Photodegradation experiment shows 83.33 % and 41 % degradation of CV and chlorpyrifos respectively. The higher degradation ability is shown by CNTs composites because they have smaller crystallite size (12.81 nm) as compared to other photocatalysts. In the presence of CNTs, the rate of recombination of holes and electrons decreases, resulting in the enhancement of photocatalytic activity. The research reveals that W-4 exhibits promising potential for applications in the photodegradation of organic wastes. [ABSTRACT FROM AUTHOR]

Carbon-based materials have a broad range of applications. Among various carbon-based materials, reduced graphene oxide (rGO) is one of the facile options for supercapacitor (SCs) fabrication. The main reason is that it offers excellent conductance and enhanced surface redox reactivity. Therefore, there is a significant possibility that this material will boost the electrochemical efficiency of pseudocapacitive materials based on transition metals. Using the sonication route, we have synthesized NiO/CoFe 2 O 4 composite and decorated it with rGO. After structural and morphological analysis, the prepared electrode materials were subjected to electrochemical energy storage efficiency studies. The obtained data showed that the NiO/CoFe 2 O 4 @rGO exhibited a higher specific capacitance of 911.25 Fg-1 as compared to other electrode materials (such as NiO/CoFe 2 O 4 , NiO, and CoFe 2 O 4). Moreover, it was observed that NiO/CoFe 2 O 4 @rGO has low equivalence series resistance (ESR) as 0.29 Ω, in comparison to NiO/CoFe 2 O 4 , NiO, and CoFe 2 O 4. The enhanced conductivity of rGO and the good crystallinity of NiO and CoFe 2 O 4 are responsible for the excellent efficiency of the NiO/CoFe 2 O 4 @rGO electrode material. According to the obtained results, the NiO/CoFe 2 O 4 @rGO nanocomposite is an effective capacitive material for supercapacitors fabrication. [Display omitted] [ABSTRACT FROM AUTHOR]

The classical co-precipitation technique was carried out for the preparation of cobalt ferrite (CFN), and Ag-doped cobalt ferrite (AgCFN). Composite with graphitic carbon nitride (AgCFN@gCN) was prepared by employing the ultrasonication method. Photocatalytic degradation activity of synthesized materials was evaluated using crystal violet (coloured compound) and benzimidazole (colourless compound) under sunlight. Various physiochemical methods such as UV–Visible, XRD, SEM, and FT-IR spectroscopy were employed for the characterization of prepared samples. XRD was used for structural characterization. The prepared nanomaterials were sized up to be < 09 nm. FT-IR spectroscopy was exploited for the functional group characterization. Surface morphology was perceived through Scanning Electron Microscope. Optical analysis was carried out using a UV–Visible spectrophotometer. The photodegradation efficiencies for crystal violet and benzimidazole were ascertained to be in the order of CFN < AgCFN < AgCFN@gCN, under sunlight. Among the synthesized photocatalysts, AgCFN@gCN was discovered to have the highest photocatalytic degradation efficiency of 52.72% and 84.21% for benzimidazole and crystal violet, respectively. The higher catalytic activity of AgCFN@gCN can be associated with its high surface area and the presence of active sites of the gCN sheets. Role of electrons (e−), holes (h+), and hydroxyl radicals (O H ∗ ) in the photocatalytic activity was also assessed. [ABSTRACT FROM AUTHOR]

In this investigation, cobalt substituted Magnesium–Zinc ferrites were successfully synthesized by using the co-precipitation technique. The prepared spinel ferrites were characterized by using Scanning electron microscopy (SEM), Ultraviolet–Visible analysis, X-ray powder diffractometer (XRD) and Fourier-transform infrared spectroscopy (FTIR). Confirmation of formation of a single-phase spinel structure was assessed by the XRD and FTIR. Crystallite size, evaluated from X-ray analysis, of MZF, MZF1, MZF2, MZF3 is 9.72 nm, 7.21 nm, 8.49 nm and 8.30 nm respectively. Cluster formation and agglomeration of powdered samples of Co substituted Mg–Zn ferrites were represented through the SEM images. The optical bandgap range was calculated from the Ultraviolet–Visible spectrum. The photocatalytic activity was assessed through the photodegradation of coloured and colourless pollutants under sunlight. This paper focuses on the photocatalytic degradation of harmful compounds like benzimidazole and methylene blue. The photocatalytic activity of Mg–Zn ferrites as a photocatalyst was enhanced by the substitution of cobalt in it. Especially, MZF3 with the highest cobalt content gave the maximum photodegradation of methylene blue. Hence, we conclude that Mg 0.5 Zn 0.5 Co x Fe 2 O 4 works as a potential catalyst in wastewater treatment. [Display omitted] [ABSTRACT FROM AUTHOR]

The breakdown of the coloured and colourless organic dyes under natural sunlight was investigated by the prepared photocatalysts. Cobalt aluminate (CoAl 2 O 4 , CA) and nickel doped cobalt aluminate (Ni–CoAl 2 O 4 , NCA) were well synthesized by an easy pechini route. Ultra-sonication route was followed to prepare composite with carbon nanotubes (CoAl 2 O 4 @CNT, NCA@CNT). The prepared catalysts were comprehensively characterized by various techniques. Spinel structure and functional groups of synthesized photocatalysts was confirmed by XRD and FT-IR techniques. The surface morphology of the synthesized materials was analyzed via SEM. The optical properties of fabricated photocatalysts were investigated via UV–Visible spectroscopy. NCA@CNT nanocomposite exhibited greater photocatalytic activity than doped and undoped photocatalysts. NCA@CNT exhibited 92.7%, 88.77%, and 63.34% photodegradation of crystal violet, methylene blue, and benzoic acid respectively. A scavenger experiment was carried out to figure out efficient photoactive species taking part in the photodegradation of organic pollutants. [Display omitted] • Simple facile route was adopted to prepare CoAl2O4@CNT Nanocomposite, a new photocatalyst. •XRD and SEM confirmed the structural and morphological aspects. •Solar light induced catalytic degradation of coloured and colorless compounds was investigated. [ABSTRACT FROM AUTHOR]

• Wet chemical routes are used for the synthesis of CuBi 2 O 4 and Bi 2 S 3. • Ultrasonication route is used to synthesize CuBi 2 O 4 /Bi 2 S 3 and CuBi 2 O 4 /Bi 2 S 3 /rGO. • XRD and FTIR confirmed the structural and spectral properties. • CuBi 2 O 4 /Bi 2 S 3 /rGO ternary composite showed excellent catalytic activity. Water pollution is the major issue to be resolved nowadays. To overcome water pollution, the use of nanotechnology proved to be an emerging field. In this project, CuBi 2 O 4 (CB-1) and Bi 2 S 3 (CB-2) were prepared by simple hydrothermal and chemical precipitation routes respectively. To enhance the effectiveness of the photocatalyst, the synthesis of CuBi 2 O 4 /Bi 2 S 3 (CB-3) and CuBi 2 O 4 /Bi 2 S 3 /rGO (CB-4) nanocomposite were carried out by ultrasonication method. Different physiochemical techniques were used to characterize the as prepared catalysts. The photocatalytic activity of fabricated catalysts was then checked for methylene blue degradation. Among all the samples, CB-4 showed the best photocatalytic performance (90.47 %) as it has low band gap energy than other fabricated materials. Therefore, the fabricated nanocomposite can be employed as a promising photocatalytic material for future use. [ABSTRACT FROM AUTHOR]

Nickel ferrites (NF), silver doped nickel ferrites (AgNF), and a composite of silver doped nickel ferrites with reduced graphene oxide (AgNF@rGO) were prepared through the co-precipitation method. The X-ray diffraction analysis was carried out to confirm the structure of prepared materials, and the crystallite size of prepared ferrites was less than 10 nm. FT-IR spectroscopy was performed for the confirmation of functional groups present in the synthesized materials. The surface morphology of prepared samples was investigated via scanning electron microscopy. Optical analysis was carried out with the help of UV–Visible spectroscopy. Thermogravimetric analysis was performed to check the thermal stability. The photocatalytic degradation of methylene blue under solar light irradiation was studied. The AgNF@rGO composite showed 76% degradation of coloured compound (methylene blue) and 50% degradation of colourless compound (benzimidazole). The enhanced photocatalytic degradation efficacy of AgNF@rGO was ascribed to the reduced graphene oxide sheets, which provided a large surface area and the ability to trap electrons from the conduction band. As a result, the decreased recombination rate of electrons and holes enhanced the degradation ability of the composite based photocatalyst. A scavenging experiment was also performed to determine the most photoactive species taking part in the degradation process. In comparison among all prepared samples, AgNF@rGO showed the maximum photocatalytic activity. It was because of the large surface area of the AgNF@rGO. It was investigated that AgNF@rGO is the most effective catalyst for the degradation of coloured and colourless organic pollutants. [Display omitted] [ABSTRACT FROM AUTHOR]

A ternary nanocomposite CuCo 2 O 4 /Co 3 S 4 @CNTs is synthesized to degrade industrial effluents. Copper cobaltite and cobalt sulfide were synthesized by adopting the coprecipitation method. The binary nanocomposite CuCo 2 O 4 /Co 3 S 4 and ternary composite CuCo 2 O 4 /Co 3 S 4 @CNT were prepared by ultrasonication. The prepared samples were used to degrade organic dye i.e. crystal violet (CV) to investigate the photocatalytic activity. The observed percentage degradation of crystal violet is 56.6%, 50.0%, 81.65%, and 90% by copper cobaltite, cobalt sulfide, their binary composite, and CNTs-based nanocomposite, respectively. The percentage degradation of the ternary composite was highest within 140 min of irradiation of visible light. The significant photocatalytic activity of CNTs based nanocomposite is because of the presence of CNT which prevents the recombination rate of charge carriers and serves as an electron mediator allowing rapid transfer of electrons from copper cobaltite to cobalt sulfide and provides greater surface area for degradation reaction. CuCo 2 O 4 /Co 3 S 4 @CNT could be a potential candidate for advanced photocatalytic applications because it is stable over 4 successive cycles. [ABSTRACT FROM AUTHOR]

• NiFe 2 O 4 was successfully synthesized via co-precipitation route. • Various physio-chemical techniques were employed to characterize the prepared samples. • The prepared photocatalysts were used for the degradation of pendimethalin under sunlight. • rGO based nanocomposite showed maximum degradation efficiency. • Gd doping and insertion of rGO sheets help to enhance the photo-degradation ability of nickel ferrite. NiFe 2 O 4 (F-1) and rare earth metal (Gd) doped NiFe 2 O 4 (F-2) were prepared via a co-precipitation approach. Gd-NiFe 2 O 4 @rGO (F-3) was prepared via an ultrasonication route for the degradation of pendimethalin under sunlight. The structural confirmation of as-fabricated samples was done via XRD. The Tauc plot of F-1 showed a bandgap energy of 2.79 eV and F-2 exhibited a bandgap energy of 2.63 eV. The optical band gap was lowered due to the presence of rare-earth metal ions. NiFe 2 O 4 and Gd-NiFe 2 O 4 showed 48.88 %, and 61.11 % degradation of pendimethalin. Gd-NiFe 2 O 4 @rGO nanocomposite showed the highest degradation efficiency. It exhibited 84.44 % degradation of pendimethalin in 140 min at the rate of 0.01 min−1. The reason for the greater activity is due to the insertion of rare earth (Gd) ions and rGO sheets in the nickel ferrite. The doping with rare earth metal ions lowers the recombination of electrons and holes which was further supported by the addition of carbonaceous material. The surface area of the nickel ferrite was improved by rGO sheets and in turn more active sites were formed on the surface of the catalyst which fastens the rate of reaction. [ABSTRACT FROM AUTHOR]

An easy approach was employed to synthesize nickel and cobalt-doped zinc ferrite (NCZF) by co-precipitation route to check photocatalytic activity. The ultrasonication method is used to synthesize nanocomposite of nickel and cobalt-doped zinc ferrite with CNT. The photodegradation of methyl violet was carried out under solar light radiations to examine the performance of a synthesized photocatalyst. Moreover, the synergistic combination of NCZF and CNTs can lower the charge carrier recombination and increase charge separation, both of which result for excellent photocatalytic activity. Methyl violet was used to accomplish the photocatalysis of ZF, NCZF, and NCZF@CNT. The fabricated samples were characterized by FTIR, XRD, and SEM. UV- Visible analysis was also employed to examine the optical properties of the synthesized material. [ABSTRACT FROM AUTHOR]

The present study investigates the photocatalytic activity of NiCoPrFe 2 O 4 and Cd-NiCoPrFe 2 O 4 synthesized by the self-ignition sol-gel process. NiCoPrFe 2 O 4 @CNTs was prepared via ultrasonication approach. Methyl violet was used as a dye to examine the photodegradation activities of synthesized photocatalysts under visible light. The spinel crystalline structure is confirmed by XRD. The morphology of the as prepared samples was observed via scanning electron microscopy. NiCoPrFe 2 O 4 , Cd-NiCoPrFe 2 O 4 , and NiCoPrFe 2 O 4 @CNTs showed 55.46%, 78.29%, and 85.96% percentage degradation of methyl violet respectively. The photocatalytic performance of CNT based nanocomposite is found to be increased due to the enhanced charge separation property of CNT. • The sol-gel method was used for the preparation of NiCoPrFe2O4. • XRD and FTIR corroborate the structure and composition of elemental features. • SEM analysis confirms the morphology of the material. • NiCoPrFe2O4@CNT composite had shown excellent result is the photo-degradation of methyl violet. [ABSTRACT FROM AUTHOR]