Sr doped TiO2 photocatalyst for the removal of Janus Green B dye under visible light.

Hydrothermal synthesis of pristine and Sr doped TiO2 is proposed. The synthesized products were studied for their physiochemical properties. 3% Sr-TiO2 showed a narrow bandgap, which facilitate an increase in oxygen vacancies. The agglomerated morphology was tuned to a nanoball structure after doping with Sr ions. Surface area was increased for the Sr doped TiO2. The samples were used to reduce Janus Green B (JG) dye as a model pollutant. The pure TiO2 showed poor efficiency, while the prepared Sr-TiO2 photocatalyst showed enhanced efficiency with a corresponding increase in the rate constant values of the samples. Tuning of the bandgap, an improvement in the morphology and an increase in the surface area were the major positives of the Sr doped TiO2 samples compared to pure TiO2, 3% Sr-TiO2 is emerging as the best photocatalyst in reducing toxic pollutants. The 3% Sr-TiO2 is a promising candidate for water remediation in the future.

Gamma irradiation effect on photocatalytic properties of Cu and Sr ions codoped PbS.

Gamma-irradiation effects on photocatalytic action of PbS nanocrystallites codoped with Cu and Sr ions were performed for organic dye degradation. The physical and chemical characterizations of these nanocrystallites were examined employing X-ray diffraction, Raman, and field emission electron microscopic analysis. The optical bandgaps of gamma-irradiated PbS with co-dopants have shifted from 1.95 eV (pristine PbS) to 2.45 eV in the visible spectrum. Under direct sunlight, the photocatalytic action of these compounds against methylene blue (MB) was investigated. Observations indicated that gamma-irradiated Pb(0.98)Cu0.01Sr0.01S nanocrystallite sample exhibits a higher photocatalytic degradation activity of 74.02% in 160 min and stability of 69.4% after three cycles, suggesting that gamma irradiation could potentially influence organic MB degradation. This is due to combined action of high-energy gamma irradiation (at an optimzed dose), which causes sulphur vacancies, and defects created by dopant ions, which alter the crystal structure by inducing strain in the crystal lattice, hence altering the crystallinity of PbS.

Conversion and reducing agent effect on zero valent iron into Fe3O4 for photocatalytic degradation under UV light irradiation.

Conversion and reducing agent (NaBH4) effect on zero valent iron into Fe3O4 nanoparticles with diverse molar ratios of reducing agent was produced through chemical reduction technique. The structural, optical, vibrational analyses were executed via XRD, UV-Vis, Raman, and FT-IR analysis. The crystallite size obtained were 35 nm, 27 nm, and 18 nm for Fe:NaBH4 (1:1), Fe:NaBH4 (1:2) and Fe:NaBH4 (1:3). The morphology of the Fe:NaBH4 (1:1) was not in good orientation with higher dimensions. As explored in Fe:NaBH4 (1:2) and (1:3) samples, there is a proper growth of nanoneedles and nanosheets formation. This was due to the addition of reducing agent which greatly helped in enhancement of morphology. The prepared photocatalysts were tested to reduce Malachite Green (MG) under UV illumination. The pure dye solution obtained 57% efficiency after irradiation. Fe:NaBH4 (1:3) photocatalyst achieved 97% efficiency on reducing pollutants. The rate constant values calculated was 0.007, 0.013, 0.02 and 0.03 min-1 for pure, Fe: NaBH4 (1:1), Fe: NaBH4 (1:2) and Fe: NaBH4 (1:3) assisted MG samples. The as prepared photocatalyst is more potential one on removal of toxic pollutants from wastewater which is due to the better enhancement of nanoneedles and nanosheets oriented by the effect of reducing agent. The advantage of Fe3O4 nanoparticles for wastewater is that the removal of these nanoparticles can be ease with magnetic separation methods. On considering the advantage of removing of photocatalyst and efficiency, this prepared product is suitable one for wastewater remediation process in future days.

Investigation of optimum Mn dopant level on TiO2 for dye degradation.

Pristine and Mn-TiO2 photocatalysts was prepared employing sophisticated hydrothermal technique. TiO2, 0.2 M, 0.4 M Mn-TiO2 photocatalysts analysis were done by using standard characterization studies. The morphology of the pure TiO2 photocatalyst showed the large agglomeration of nanoparticles. While the dopant Mn ions influenced higher on host lattice TiO2. The 0.2 M Mn added TiO2 photocatalyst showed no agglomeration and nanoparticles size were decreased. On increasing dopant level, there is growth of nanorods along with nanoparticles which greatly helped in dye degradation. The prepared photocatalysts photocatalytic action was investigated on reducing MG dye. Prepared photocatalyst added dye mixtures were exposed under visible light and collected for every 15 min. 0.4 M Mn-TiO2- MG sample showed 96% efficiency on degrading MG dye. The dopant has increased electrons and holes recombination on host surface. 0.4 M Mn-TiO2-MG sample rate constant was higher than other samples and reaction system abide by Pseudo first order kinetics. 0.4 M Mn-TiO2 photocatalyst be an efficient and enthusiastic potential material to remove organic pollutants.

Effect of grinding time on bismuth oxyhalides optical and morphological properties influence on photocatalytic removal of organic dye.

Herein, we reported the synthesis of BiOX (X = Cl, Br) with different grinding time like 15 min and 30 min to analyze the evolution of physiochemical properties and the morphological evolution. The structural, optical, vibrational properties were examined by standard characterization studies. The formation of bismuth oxyhalides were confirmed by XRD and Raman studies. The crystallite size was decreased as in 30 min grinded sample whereas there is an influence of crystal structure. BiOCl (15 and 30 min) samples expelled the nanoflake like structure with the flakes arranged to form a nanoflower morphology. On comparing BiOCl (15 min), there is high orientation of nanoflakes on BiOCl (30 min) sample. As explored in BiOBr (15 and 30 min) samples, the development of nanoplates were found. The growth of nanoplates was enhanced in the better way in BiOBr (30 min) than BiOBr (15 min). The grinding time has explored a great influence on morphology. The photocatalyst test for prepared photocatalysts was performed to reduce the RhB dye. The photocatalysts showed 74%, 97%, 98% and 99.8% for BiOCl (15 min), BiOCl (30 min), BiOBr (15 min) and BiOBr (30 min). The rate constant value obtained was 0.008, 0.011, 0.021, 0.033 and 0.068 min-1. BiOBr (30 min) sample achieved higher rate constant value. The hierarchical nanostructures and narrow bandgap has made the samples to be a potential candidate to reduce the toxic pollutants with complete efficiency.

Surfactant induced copper vanadate (ß-Cu2V2O7, Cu3V2O8) for different textile dyes degradation.

In this study, pristine ß-Cu2V2O7, CTAB-ß-Cu2V2O7 and PVP-Cu3V2O8 were synthesized via hydrothermal method. The synthesized brown powder samples were exemplified using XRD, UV, PL, Raman and SEM studies. Further with XRD, we confirmed that the impurities were eradicated in addition of surfactant PVP. The bandgap obtained were 3.09 eV, 2.97 eV and 2.28 eV for ß-Cu2V2O7, CTAB-ß-Cu2V2O7 and PVP-Cu3V2O8. The morphology of ß-Cu2V2O7 was found to be cluster of nanoparticles with high level of agglomeration. While adding the surfactants (CTAB, PVP) the nano platelets were grown and uniformly arranged. The PVP-Cu3V2O8 sample exhibited 96%, 77% and 96% efficiency on reducing Methylene Blue, Rhodamine B and Malachite Green dyes. The enhancement of attaining complete efficiency by the PVP-Cu3V2O8 photocatalyst is attributed by the appropriate phase of host material and the PVP itself acted as a trapper for electron and hole which induced the rate of degrading toxic pollutants. The PVP-Cu3V2O8 photocatalyst will be enthusiastic and optimized aspirant for reducing organic pollutants and for wastewater management in future days.

Facile hydrothermal synthesis of MXene@antimony nanoneedle composites for toxic pollutants removal.

A new 2D transition metal carbides family noted that MXene with antimony (Sb) nano-needles composites have demonstrated potential applications for photocatalytic dye degradations applications. Single-step synthesis of novel structures two/one-dimensional MXene@antimony nanoneedle (MX@Sb-H) nanocomposite-based photocatalysts is produced employing hydrothermal technique. The preparations and characterizations were compared with hand mixture preparations of pure TiO2@Sb and MXene (MX@Sb-M). The crystallographic structure was identified employing X-ray diffraction (XRD) studies and main sharp XRD peaks were observed with diffraction angle with orientations planes for all three samples TiO2@Sb, MX@Sb-M and MX@Sb-H. The micro-Raman spectroscopy explored key vibration modes centered at 151.72 and 637.52 cm-1 corresponding to Ti and Sb hybrid composites respectively. Fourier transform infrared spectroscopy (FTIR) spectrum of functional group peaks at 609.16 and 868.80 cm-1 revealed Ti-OH/Sb-O-C stretching. The morphological investigations of horizontal growth for "Sb" nanoneedle on MXene nanosheets were explored by scanning electron microscopy (SEM). The degradation efficiency was calculated. The efficiency calculated were 27%, 38%, 68% and 82% for MB solution, TiO2@Sb added MB, MX-Sb-M added MB and MX-Sb-H added MB solution and the efficiency were 32%, 38%, 50% and 65% for pure RhB solution, TiO2@Sb added RhB, MX-Sb-M added RhB and MX-Sb-H added RhB solution. The photocatalytic activity of TiO2@Sb, MX@Sb-M and MX@Sb-H was examined. Among these MX@Sb-H nanocomposite was demonstrated the high photocatalytic action in expressions of rate stability of photocatalytic dye degradations.

Fabrication of Ce doped TiO2 for efficient organic pollutants removal from wastewater.

Pristine and Ce doped TiO2 nanoparticles were fabricated for toxic pollutants removal from wastewater. Pristine, 2% Ce and 4% Ce doped TiO2 photocatalysts were produced via hydrothermal route. 4% Ce doped TiO2 exhibited 2.41 eV bandgap which is smaller than pure TiO2. The morphology was also investigated and it was established that doping of Ce ions enhanced the surface roughness and reduced the particle size. The surface area was characterized through BET analysis and 4% Ce-TiO2 possess higher surface with large pore diameter which helped the photocatalytic activity. The prepared photocatalysts were investigated on reduction of pollutants from wastewater under visible light. Higher efficiency was obtained for 4% Ce-TiO2 photocatalyst for both model pollutants. The "k" value possessed was also higher for the doped TiO2 catalyst. These analysis reports the optimum level of ceria doping to enhance morphology, surface area and it increased activity than bare TiO2. 4% Ce-TiO2 will be the potential candidate for efficient wastewater management. The 4% Ce doped TiO2 photocatalyst provided 77% and 88% on reducing MB and RhB dyes. The dopant has developed higher surface area, morphology and good recombination rate which reduced the toxic pollutants and changed the wastewater to reuse.

Investigation of pure and g-C3N4 loaded CdWO4 photocatalytic activity on reducing toxic pollutants.

A facile synthesis of pristine and g-C3N4 loaded CdWO4 (Cadmium Tungstate) were reported and analyzed the effect of pollutants removal in wastewater. The samples were characterized and the morphology of the pristine sample showed the nanostructures with high cluster of layer formed. While adding PEG (Polyethylene glycol), the surface has exhibited less agglomeration and in g-C3N4 added sample the agglomeration was intensely reduced and nanostructures have been clearly found. Photocatalytic performance on cationic dye was investigated under visible light. The efficiency calculated for g-C3N4- CdWO4 sample was 85% for MB. The C/C0 plot gives better degradation. The kinetic study revealed pseudo first order reaction. The g-C3N4-CdWO4 sample exhibited higher "k" value which proved best efficiency on removing the pollutant. g-C3N4-CdWO4 sample will make better reduction on toxic pollutants and be a good candidate in futuristic applications. By carbon based derivates inclusion with photo active materials, the morphology and surface area was greatly improved and it enhances activity of host material and it will be the promising material for industrial applications.

Facile single-step synthesis of MXene@CNTs hybrid nanocomposite by CVD method to remove hazardous pollutants.

In the present work, facile preparation of MXenes based nanocomposite (MXene-CNTs) through catalytic chemical vapor deposition (cCVD) was demonstrated. The novel design of two and one-dimensional (2D/1D) MXene-CNTs composites for an extraordinary photocatalytic process for removal of Rhodamine B (RhB) using efficient photocatalytic dye degradations was compared to the performance of pure MXene. The surface morphological behavior of MAX, MXene and MXene-CNTs rational design of surface microstructure CNTs anchored on 2D materials MXene nanosheets product was characterized employing scanning electron microscopy (SEM). As-prepared direct growth CNTs by employing CVD method were in the size ranges of 40-90 nm as revealed from SEM images. The crystallographic structures of etching and delaminations of MAX and MXene-CNTs were observed for CNTs diffracted peaks at 2θ = 25.11° in support of (002) plan. The major C-O and (CC) stretching were confirmed. Prepared MXene and MXene-CNTs samples photocatalytic performance was investigated through photocatalytic Rhodamine B (RhB) dye degradation. MXene-based CNTs hybrid nanocomposites photocatalysts activity were estimated. The as-prepared pure MXene-RhB and MXene-CNTs-RhB materials calculated efficiency were 60 % and 75 %, respectively. The CVD preparations of new MXene-CNTs synthesis yield high and explored good successive cycles for hazardous pollutants.

Investigation of PEG directed Sb2WO6 for dyes removal from wastewater.

Pristine and polyethylene glycol assisted antimony tungstate (Sb2WO6) was developed via hydrothermal route. The pristine and surfactant assisted Sb2WO6 were further exemplified to reveal the properties of the samples. The bandgap calculated for Sb2WO6, 5 ml PEG- Sb2WO6, 10 ml PEG- Sb2WO6 was 2.78 eV, 2.66 eV and 2.21 eV. The 10 ml PEG assisted sample exhibited narrow bandgap. The Fourier transform infrared spectroscopy (FTIR) spectra of the samples showed metal vibrations and stretching of the water molecules adsorbed. The Raman spectra showed the vibrational modes present in Sb2WO6. The morphology was analyzed employing transmission electron microscope (TEM) for all samples. Pristine Sb2WO6 showed growth of nanorods with higher dimensions with high agglomeration. 5 ml PEG- Sb2WO6 showed the growth of nanorods with lesser agglomeration. 10 ml PEG assisted Sb2WO6 exhibited distinct growth of nanorods with no agglomeration on the surface. The elemental composition was examined employing X-ray Photoelectron Spectroscopy. Prepared product photocatalytic behaviour was tested employing Rhodamine B dye degrading. Different catalyst loading were investigated for degrading the toxic pollutants. 0.2 g 10 ml PEG-Sb2WO6 showed 81% efficiency on degrading the toxic pollutant from wastewater. The OH radicals are accountable for photocatalytic behaviour of prepared photocatalyst. The 10 ml PEG-Sb2WO6 has the good reusability behavior and stable properties after three cycles. The prepared 10 ml PEG- Sb2WO6 photocatalyst will be the potential candidate for the remediation of the water treatment.

Synthesis of pure and lanthanum-doped barium ferrite nanoparticles for efficient removal of toxic pollutants.

Treatment of wastewater for reuse is an important strategy undertaken to deal with water scarcity. In this study, pure and La-doped barium ferrites were produced using a facile hydrothermal technique. Lanthanum was doped at 1% and 2% molar ratio and the obtained product was analyzed for further confirmation of crystal structure, optical properties, vibrational properties, and morphology. X-ray powder diffraction pattern confirmed material formation. Bandgap energies were estimated from a Tauc plot. The vibrational properties of the pure and doped samples were examined by Fourier-transform infrared spectra. The pure barium ferrite sample showed a spherical agglomerated morphology. The 1% La-doped barium ferrite sample showed reduced agglomeration and the particles were attached together. The 2% La-doped barium ferrite sample showed small nanoballs with no agglomeration on the surface. The transmission electron microscopy images confirmed no agglomeration for the 2% La-BaFe2O4 sample. The M-H loop revealed the ferromagnetic behavior of the pristine and doped samples. The 2% La-BaFe2O4 sample had 24.53 m2/g surface area. The photocatalytic activity was examined employing degrading methylene blue under ultraviolet (UV) and visible light. Prepared product showed better efficiency on UV light exposure. The 2% La-doped barium ferrite sample exhibited almost 80% of efficiency under UV light and 85% efficiency under visible light toward toxic pollutants. The sample attained 0.02 min-1 rate constant value. The main advantage of ferrite samples is that the particles can be separated by magnetic methods and the water will be fit for reuse. The sample will be a promising candidate for use in the wastewater treatment.

Efficient photocatalytic degradation of hazardous pollutants by homemade kitchen blender novel technique via 2D-material of few-layer MXene nanosheets.

To attain elevated class MXene (Ti3C2Tx) through a homemade kitchen blender method, high shear mechanical exfoliation is highly required for the efficient delimitations of MXene nanosheets from bulk MAX (Ti3AlC2). We examine large-scale industrial productions of the MXene nanosheets, where combing the predicted 2D materials using a blender is a first-time novel approach with the delaminating solvent as a dimethyl sulfoxide (DMSO). And also manually created layered MXene systems (handmade) delaminating MXene sheets (MX-H) was furthermore employed for environmental dye-degradations applications. The materials characterizations was done for both the bulk MAX, MX-H and the MX-B. Additionally, the surface morphological studies like scanning electron microscopy (SEM) were investigated for both MX-H and MX-B as-prepared samples. SEM images indicated the high shear blander technique formations highly expanded/delaminated MXene (Ti3C2Tx) nanosheets compared to MX-H samples. FTIR technique is employed to identify -OH, C-H, C-O stretching vibrations for both materials. Raman spectroscopy analysis of MX-H and MX-B revealed 484.80 cm-1 Raman shift assigned to E1g phonon mode of (Ti, C, O). The ultraviolet UV visible absorption spectra explored pure and catalyst added Methylene Blue (MB) dye stock solution using annular type photoreactor with visible light source of 300 W. The comparatives of MAX, MX-H and MX-B samples was investigated as photocatalytic activity, The blender made (MX-B) sample revealed 98% of efficiency.

Pure and Ce-doped spinel CuFe2O4 photocatalysts for efficient rhodamine B degradation.

Wastewater management is becoming a serious issue worldwide. To enhance the reuse of wastewater, one has to remove toxic pollutants present in it. High amount of dye is present in wastewater, and to remove these dyes is the large scope of this research. Herein, we report production of pure and Ce-doped copper ferrite via hydrothermal route. The synthesized nanoparticles were collected and analyzed by basic characterization techniques. The bandgap energy calculated for pure, 1% Ce, and 2% Ce-doped CuFe2O4 was found to be 2.77, 2.57, and 2.36eV, respectively. Reduction in bandgap was attributed to the doping element. The shape and size of pure and Ce-doped products were investigated using a scanning electron microscope. Agglomeration was observed in the pure copper ferrite sample. In the Ce-doped sample, agglomeration was clearly reduced and the 2% Ce-doped CuFe2O4 sample showed growth of small nanoparticles. They showed complete growth and were arranged in a uniform manner without agglomeration. The surface area of the 2% Ce-CuFe2O4 sample was found to be 65.89 m2/g with 7.02 nm pore diameter. The photocatalytic activity of the prepared material was observed for rhodamine B degradation. The pure and catalyst-added dye was exposed under visible light. The samples were tested for UV. The efficiency obtained for pure dye solution, pristine CuFe2O4-added, and 1% Ce and 2% Ce-doped CuFe2O4-added dye solutions were 48%, 50%, 66%, and 88% within 2 h of irradiation. The 2% Ce-doped CuFe2O4 sample showed excellent photocatalytic activity as the bandgap and morphology were enhanced by doping an appropriate ratio of Ce ions.

Investigation on (Zn) doping and anionic surfactant (SDS) effect on SnO2 nanostructures for enhanced photocatalytic RhB dye degradation.

Herein we reported the effect of doping and addition of surfactant on SnO2 nanostructures for enhanced photocatalytic activity. Pristine SnO2, Zn-SnO2 and SDS-(Zn-SnO2) was prepared via simple co-precipitation method and the product was annealed at 600 °C to obtain a clear phase. The structural, optical, vibrational, morphological characteristics of the synthesized SnO2, Zn-SnO2 and SDS-(Zn-SnO2) product were investigated. SnO2, Zn-SnO2 and SDS-(Zn-SnO2) possess crystallite size of 20 nm, 19 nm and 18 nm correspondingly with tetragonal structure and high purity. The metal oxygen vibrations were present in FT-IR spectra. The obtained bandgap energies of SnO2, Zn-SnO2 and SDS-(Zn-SnO2) were 3.58 eV, 3.51 eV and 2.81 eV due to the effect of dopant and surfactant. This narrowing of bandgap helped in the photocatalytic activity. The morphology of the pristine sample showed poor growth of nanostructures with high level of agglomeration which was effectively reduced for other two samples. Product photocatalytic action was tested beneath visible light of 300 W. SDS-(Zn-SnO2) nanostructure efficiency showed 90% degradation of RhB dye which is 2.5 times higher than pristine sample. Narrow bandgap, crystallite size, better growth of nanostructures paved the way for SDS-(Zn-SnO2) to degrade the toxic pollutant. The superior performance and individuality of SDS-(Zn-SnO2) will makes it a potential competitor on reducing toxic pollutants from wastewater in future research.

Anionic surfactant assisted copper hydroxide for toxic dye removal from wastewater.

Wastewater treatment is the most important criteria that will deliberately reduce the water scarcity and to remove the organic pollutants from water. In this study, pure copper hydroxide (Cu(OH)2), 1% sodium dodecyl sulphate (SDS) and 2% sodium dodecyl sulphate (SDS) assisted Cu(OH)2 was prepared through co-precipitation technique. The prepared samples was investigated employing standard characterization studies. The X-Ray diffraction (XRD) pattern was confirmed with JCPDS card # 80-0656 with crystallite size of 25, 23 and 21 nm for pure Cu(OH)2, 1% SDS and 2% SDS assisted Cu(OH)2. The bandgap energy obtained for Cu(OH)2, 1% SDS and 2% SDS assisted Cu(OH)2 were 2.86 eV, 2.81 eV and 2.72 eV. The narrow bandgap of 2% SDS assisted Cu(OH)2 enhanced the photocatalytic activity than other two samples. The formation of nanoclusters and nanosheets were confirmed with Scanning Electron Microscopic (SEM) analysis. The thick clumsy nanosheets are formed as large nanoclusters in pure Cu(OH)2. Addition of SDS reduced the thickness of nanosheets and formed a little cluster. The prepared product photocatalytic performance was examined employing degradation of Methylene Blue (MB) dye. 2% SDS assisted Cu(OH)2 added MB dye solution was completely degraded with 98% efficiency. The reduce in particle size, high recombination of electron-hole pair with narrow bandgap made the 2% SDS assisted Cu(OH)2 candidate to give out potential output in eliminating the organic pollutants.

Rare earth metal (Sm) doped zinc ferrite (ZnFe2O4) for improved photocatalytic elimination of toxic dye from aquatic system.

Wastewater remediation is the serious topic that must be taken into concern which would be a most crucial problem that destroys the natural properties as well as it has some worse effect on living organisms. By doing better wastewater management, the scarcity of water for domestic purposes can be eventually managed. Dyes are main organic pollutant that must be removed from wastewater. Pristine, 1% Sm doped and 2% Sm doped ZnFe2O4 were prepared through simple co-precipitation method. The materials were further analyzed for its structure, optical properties, rotational properties and morphology studies. These analyses were investigated with respect to X-ray diffraction, UV-vis spectroscopy, photoluminescence and scanning electron microscopic studies. XRD pattern of Pristine, 1% Sm doped and 2% Sm doped ZnFe2O4 was matched with JCPDS Card #89-1012 with cubic phase. Bandgap energy of prepared samples were 1.7 eV, 1.65 eV and 1.47 eV. The prepared cationic dye was degraded with help of visible light irradiation. 2% Sm doped ZnFe2O4 nanoparticles easily removed 65% of dye within 1 h duration. 2% Sm doped ZnFe2O4 was tested for its reusability and efficiency was stable for more than three cycles. This shows the stability of the sample towards degrading the cationic dye. By the doping of Samarium, ZnFe2O4 nanoparticles enthusiastically removed cationic dye and it proves to be an efficient candidate in removing dyes and can help in wastewater treatment in upcoming era.

Influence of tin (Sn) doping on Co3O4 for enhanced photocatalytic dye degradation.

Wastewater remediation is one of the special issues that have been discussed in recent years and one of the main pollutants was dyes which totally changes the water behavior. To eradicate the organic compounds from the wastewater and reuse it, there are numerous steps have been taken into consideration. Dye degradation via photocatalysis is one of the promising technique with good efficiency. Pure and tin (Sn) doped Co3O4 was prepared employing co-precipitation technique. The structural, vibrational, optical and morphological analysis was done employing X-ray diffraction studies, Photoluminescence, Raman analysis and Scanning Electron Microscopic (SEM) studies. The well-defined nanoparticles were grown with 1 M Sn doped Co3O4. The photocatalytic activities of methylene blue dye under visible light were investigated by adding the samples (CS-1, CS-2, CS-3). 1 M Sn doped Co3O4 sample showed 75% efficiency towards dye degradation. The prepared 1 M Sn doped Co3O4 sample will be the best for photocatalytic activity. By doping Sn atoms the efficiency of the host is increased which will be the most promising candidate for the photocatalytic dye degradation applications.

PVP influence on Mn-CdS for efficient photocatalytic activity.

Wastewater treatment is the most serious problem in this upcoming era. A harmful effluent like organic dyes, heavy metals, acids from industries mixed in wastewater is deteriorating the environment. To get rid of these poisonous materials and to recycle wastewater for domestic purposes, there are many steps which included photocatalytic dye degradation. PVP assisted Mn-CdS nanoparticles was prepared by novel hydrothermal technique. The characteristic behavior of pure and PVP (1% and 2%) assisted Mn-CdS samples were studied by further analysis. The structural, optical, vibrational, morphological, chemical composition behavior of synthesized pristine and surfactant induced Mn-CdS nanoparticles were analyzed. UV-Vis spectra revealed the optical behavior of the prepared pure and PVP (1% and 2%) assisted Mn-CdS samples. The bandgap obtained was 2.2, 2.06 and 1.99 eV for pure Mn-CdS, 1% PVP-Mn-CdS and 2% PVP- Mn-CdS. The narrow bandgap is one of the advantage of the material. Mn-CdS, 1% PVP-(Mn-CdS) and 2% PVP- (Mn-CdS) morphology were further investigated by Scanning Electron Microscopic studies (SEM). The surfactant (PVP) was added to enhance the morphology development and decrease agglomeration on the surface and the SEM images revealed a clear evidence for enhancement of morphology in all three samples. 2% PVP-(Mn-CdS) sample showed a good development in morphology when compared with other two samples and the best sample showed formation of nanorods below the surface of nanoparticles. Further, Mn-CdS, 1% PVP-(Mn-CdS) and 2% PVP- (Mn-CdS) was indulged to investigate the cationic degradation. The photocatalytic activities of three samples were carried out with loading different amount of the catalysts and 30 mg catalyst 2% PVP- (Mn-CdS) loaded dye solution showed a considerable degradation of methylene blue dye. The 30 mg catalyst (2% PVP-Mn-CdS) showed 98% efficiency under visible light irradiation for about 2 h. The best candidate, 30 mg catalyst (2% PVP-Mn-CdS) investigated for its reusability. The catalyst showed almost 98% of efficiency up to three cycles which confirmed the level of potential of the sample. 2% PVP-(Mn-CdS) sample would be promising candidate in wastewater treatment. It can be further utilized for removing dyes from wastewater in wastewater remediation process.

A strategy to enhance the photocatalytic efficiency of α-Fe2O3.

The photocatalytic dye degradation of pure α-Fe2O3 and different concentration of Co doped α-Fe2O3 is explored. Facile hydrothermal method were employed to prepare pristine, 2% and 4% Co-Fe2O3 nanoparticles. Further, synthesized product confirmation studies were employed from X-ray diffraction, UV-vis spectrometry, Fourier-transform infrared, Raman, scanning electron microscope and transmission electron microscope studies. The rhombohedral nanoparticles developed were enhanced photocatalytic action. Photocatalytic dye degradation studies were analyzed for prepared three samples and the photocatalytic efficacy of the obtained photocatalysts was compared experimentally. Methylene blue dye was degraded under UV-light irradiation with 364 nm. The results showed that 4% Co doped α-Fe2O3 sample exhibited better dye degradation with 92% efficiency. The 4% doping of cobalt ions enhanced the photocatalytic property of Fe2O3 and is a good candidate for methylene blue dye degradation above 90%. In addition, strategy for photocatalytic efficiency enhancement was proposed.