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The design and engineering of plasmonic metal nanocomposite photocatalysts offer an operative approach for highly efficient CO2 photoreduction. Herein, the authors report a plasmonic 3D flower-like...

Synthesizing nanomaterials at the expense of solar energy and the associated energy generation have utmost significance as far as environmental sustainability is concerned. Here, sunlight-assisted ...

Efficient production of hydrogen through photocatalytic water splitting requires innovative catalyst design. One of the potential ways to enhance the photocatalyst's efficiency is to prepare metal oxide heterostructures. Herein, we report fabrication of a novel heterostructure consisting of oxides of cesium, bismuth, titanium and zinc (Cs2O–Bi2O3–TiO2–ZnO) by a simple solution combustion method. Diffusion pathway of charge carriers in the as-synthesized Cs2O–Bi2O3–TiO2–ZnO is investigated by high resolution Valence Band X-Ray Photoelectron Spectroscopy (VB-XPS) and electron spin resonance studies. On the basis of analytical findings and redox potential values of each photocatalytic component, a plausible mechanism is proposed showing the formation and diffusion of charge carrier. The results suggest that the charge carrier migration follows the heterojunction approach among TiO2, Bi2O3, and ZnO and the Z-scheme approach between each of them and Cs2O. The performance of the as-obtained catalytic system is investigated by quantifying the photocatalytic formation of oxygen and hydrogen gases, as well as photoelectrochemical water oxidation under simulated sunlight irradiation. In addition, the apparent quantum efficiency is estimated as high as 1.56% at 420 nm. The high apparent quantum efficiency is primarily ascribed to the synergetic effect between Z-scheme and heterojunction operative in the as-prepared heterostructure.

Synthesis of metal oxide nanostructures through combustion routes is a promising technique owing to its simplicity, rapidity, scalability, and cost-effectiveness. Herein, a sunlight-driven combustion approach is developed to synthesize pristine metal oxides and their heterostructures. Sunlight, a sustainable energy source, is used not only to initiate the combustion reaction but also to create oxygen vacancies on the metal oxide surface. ZnO nanostructures are successfully synthesized using this novel approach, and the products exhibit higher photocatalytic activity in the decomposition of methyl orange (MO) than ZnO nanostructures synthesized by the conventional methods. The higher photocatalytic activity is due to the narrower band gap, higher porosity, smaller and more uniform particle size, surface oxygen vacancies, as well as the enhanced exciton dissociation efficiency induced by the sunlight. Porous Fe3O4 nanostructures are also prepared using this environmentally benign method. Surprisingly, few-layer Bi2O3 nanosheets are successfully obtained using the sunlight-driven combustion approach. Moreover, the approach developed here is used to synthesize Bi2O3/ZnO heterostructure exhibiting a structure of few-layer Bi2O3 nanosheets decorated with ZnO nanoparticles. Bi2O3 nanosheets and Bi2O3/ZnO heterostructures synthesized by sunlight-driven combustion route exhibit higher photocatalytic activity than their counterparts synthesized by the conventional solution combustion method. This work illuminates a potential cost-effective method to synthesize defective metal oxide nanostructures at scale. Copyright - 2019 American Chemical Society. This study was supported by University Grants Commission, India, under University with Potential for Excellence (UPE) program at University of Mysore, UGC JRF (Award No. F.19-1/2013(SA-I)), and Deanship of Scientific Research (DSR) at King Fahd University of Petroleum & Minerals (KFUPM) through project no. DF181021. Scopus

A novel NLO compound (E)-1-(5-chlorothiophene-2-yl)-3-(4-dimethylamino) phenyl) prop-2-en-1-one has been synthesized by adopting claisen schmidt condensation reaction method and the single crystals are grown using slow solvent evaporation technique. The FT-IR spectrum confirms the various functional groups present in the compound. The crystal structure was studied by XRD method, which reveals that the compound crystallizes in Monoclinic crystal system with a space group P21/n and the corresponding lattice parameters are a = 7.595 (2) Å, b = 17.441 (4) Å, c = 10.917 (3) Å, α = 90o, β = 102.500 (12)o, γ = 90o. UV-Visible spectrum shows that the crystal is transparent in the entire visible region. Refractive index of the crystal was determined using Brewster’s angle method. Thermal stability of the material was determined from TG/DTA test. The Second harmonic generation efficiency of the crystal was estimated using NLO test and the efficiency was found to be 0.84 times that of UREA.

A novel heterocyclic compound, 1-(4-methoxy phenyl)-2-((5-(1-(naphthalen-1-yloxy) ethyl) -[1,3,4]-oxadiazol-2-yl) sulfanyl) ethanone was synthesized using standard method and chemical structure of the synthesized compound was identified using FTIR spectrum. Needle shaped single crystals have been grown using solution growth technique. The grown crystals were characterized using single crystal XRD, UV-visible and Thermal analysis. The crystal structure study shows that the compound crystallizes in Monoclinic crystal system with a space group of P21/a and cell parameters are determined. UV-Visible study shows that the crystal is transparent in the entire visible region. The thermal stability of the material was determined by TG and DTA analysis.

Bio-hydrothermally synthesized ZnO nanoparticles (NPs) were coated ex situ on degummed silk fibers and subjected for X-ray diffraction, Scanning Electron Microscopy, and Energy dispersive spectroscopic characterization. Both coated and/uncoated fibers were sterilized by autoclave and ethylene oxide. Effect of coating and sterilization on mechanical properties of fibers was evaluated measuring its tensile strength. Antibacterial efficacy of coated fibers was assayed against Staphylococcus aureus. PXRD of uncoated and ZnO NPs coated fibers fairly differ, with former exhibiting highly amorphous nature and latter showing additional ZnO peaks at 34.42° and 36.41° corresponding to (002) and (101) planes with decreased amorphousness. SEM demonstrated spherical and agglomerated NPs on entire fiber surface and EDS confirmed presence of Zn. Coated fibers had significant improvement in tensile strength, measuring 2.2 N/m2 against 0.82 N/m2 of uncoated silk fibers. Autoclaving affected tensile strength of both coated and uncoated fibers detrimentally though coated fibers showed better resistance. Antibacterial activity of coated fibers was excellent on day 2 (1.9 cm zone of inhibition), which gradually declined by 6th day showing that coated fibers have consistent antibacterial activity against S. aureus. Hence, coating with ZnO NPs caused improvement in mechanical properties and antibacterial properties of degummed silk fibers, which could be a potent biomaterial for biomedical applications.

A facile fabrication and processing of cerium oxide-graphene oxide (CeO2-GO) hybrid nanocomposites without the use of any surfactant or any organic solvents using chemical method and treatment with microwave irradiation technique are reported. In-situ hexagonal nano cerium oxide particles embedded on the layered surface of GO sheets were investigated for the photodegradation of dyes, removal of chromium Cr(VI) ions and against antibacterial studies. The results imply that hybrid nanocomposites shows enhanced 5-folds of photocatalytic activities in UV (ultraviolet) light irradiation and exhibited rapid efficiency in the elimination of chromium ion better than the pure GO and CeO2, which are inhibited by competent photosensitive electron inoculation and controlling the electron-hole recombination. The synergetic effect of CeO2-GO composites played a vital role in showing better results against model bacterium than GO and CeO2 are due to higher physical interaction endorsed to the stress of membranes acute by piercing edges, large surface area, and higher adsorptive conditions of graphene oxide sheets tailored with ceria particles. The amount of charge transferred at the interface increases with the concentration of O atoms, demonstrating the interaction between CeO2 and GO is much stronger than CeO2 and GO are due to the decrease of the average equilibrium distance between the interfaces. The CeO2-GO interface staggered band alignments existing between the CeO2 surfaces and GO which shows an excellent synergism. The structure and morphology of composites were tested by X-ray diffraction (XRD), Fourier transform infrared (FTIR), Raman, X-ray photoelectron spectroscopy (XPS), and high-resolution transmission electron microscope (HR-TEM).

Limited light absorption, inefficient electron-hole separation, and unsuitable positions of conduction band bottom and/or valence band top are three major critical issues associated with high-efficiency photocatalytic water treatment. An attempt has been carried out here to address these issues through the synthesis of direct Z-scheme Cs2O-Bi2O3-ZnO heterostructures via a facile, fast, and economic method: solution combustions synthesis. The photocatalytic performances are examined by the 4-chlorophenol degradation test under simulated sunlight irradiation. UV-vis diffuse reflectance spectroscopy analysis, electrochemical impedance test, and the observed transient photocurrent responses prove not only the significant role of Cs2O in extending light absorption to visible and near-infrared regions but also its involvement in charge carrier separation. Radical-trapping experiments verify the direct Z-scheme approach followed by the charge carriers in heterostructured Cs2O-Bi2O3-ZnO photocatalysts. The Z-scheme charge carrier pathway induced by the presence of Cs2O has emerged as the reason behind the efficient charge carrier separation and high photocatalytic activity. Qatar University, Shenzhen Polytechnic, Southern University of Science and Technology, King Fahd University of Petroleum and Minerals, Excellent Young Talents Fund Program of Higher Education Institutions of Anhui Province, Ministry of Science and Technology of the People's Republic of China, National Natural Science Foundation of China Scopus

This article reports the influence of sintering temperature on the structural, dielectric and ferroelectric properties of lead-free Ba0.98La0.01Na0.01TiO3 ceramics synthesized by conventional solid-state reaction technique. The calcination of the ceramic powders has been accomplished using microwave system at 1000 °C for 30 min and sintered at four different temperatures, i.e., 1250, 1300, 1350 and 1400 °C for 4 h. The XRD analysis along with Rietveld refinement confirms that all samples show a single phase tetragonal structure. The confirmation of tetragonal phase structure has been carried out using Raman study. The elemental composition and chemical states of the sintered pellets have been determined using XPS study. The investigation of Scanning Electron Microscopy (FE-SEM) revealed that the grain size increases with rising sintering temperature. The temperature and frequency dependence of dielectric properties has been investigated using Impedance spectroscopy in the frequency range of 60 Hz −1 MHz and temperature range of RT to 150 °C. The Ba0.98La0.01Na0.01TiO3 ceramic sintered at 1350 °C obtains the optimum dielectric constant of 2583 and dielectric loss

A new chalcone, 1-(3,4-dimethoxyphenyl)-3-(3-hydroxyphenyl)prop‑2-en-1-one (3), was synthesized, characterized by spectroscopy (IR, 1H, 13C NMR, LC-MS) and single crystal X-ray diffraction method. The compound crystallizes in the monoclinic crystal system (space group C2/c) with unit cell dimensions a = 34.940(6) A, b = 5.4090(9) A, c = 16.668(3) A, β = 108.400(8)°, Z = 8, and V = 2989.1(9) A3. The dihedral angle between the terminal phenyl ring is 16.39 (10)o and intramolecular hydrogen bond of the type C-H…O is observed. The intermolecular hydrogen bonds (O-H…O and C-H…O) and short contacts of the type C-H…π were involved in the crystal structure stabilization. The O-H…O and C-H…O intermolecular hydrogen bond generates R22(18) and R22(14) ring motifs, respectively. The intercontacts in the crystal packing were analyzed using Hirshfeld surfaces method using 2D fingerprint plots and electrostatic potential surfaces. The major intercontact contributing to the Hirshfeld surfaces are found to be from H…H and C…H. In addition, the thermal analysis shows two-step degradation of the 3.

Despite numerous reports have investigated the effect of morphology on the properties of nanomaterials, its role in tuning nanomaterials properties is still not clear to date. This work introduces a unique attempt to explore the correlation among morphology, surface defects (oxygen vacancies), and properties of nanomaterials. To achieve this task, three different morphologies of ZnO nanoflowers were prepared via hydrothermal method by varying the concentration of diethylamine. It was observed that a change in ZnO nanoflowers morphology results in changes in their optical, photocatalytic, and antibacterial properties. Photoluminescence and X-ray photoelectron spectroscopy analyses reveal the presence of oxygen vacancies (VO) in ZnO nanoflowers with a concentration varies with respect to morphology. VO concentration plays a key role in tuning ZnO band gap and the concentration of reactive oxygen species and thereby tuning optical, photocatalytic, and antibacterial properties of ZnO nanoflowers. Our results suggest that VO concentration, morphology, and properties of ZnO nanoflowers are correlated.

This study demonstrated a solvothermal method of growth of three different morphologies of zinc oxide nanoparticles (ZnO NPs): i) flower-like nanorod and nanoflakes, ii) assembled hierarchical structure, and iii) nano granule. Oleic acid (C 18 H 34 O 2 ), gluconic acid (C 6 H 12 O 7 ) and tween 80 (C 64 H 124 O 26 ) were used as surfactant/capping/reducing agent for the formation of different morphologies of nanoparticles. The as-synthesized ZnO NPs were characterized by different physicochemical techniques such as UV–vis (UV–vis) spectroscopy, X-ray diffraction (XRD), fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray (EDX) analysis and dynamic light scattering (DLS) studies. Further, the antioxidant and antimicrobial activity of these nanostructures was evaluated. The antioxidant activity of these nanostructures was assessed via 2,2-diphenyl,1-1 picrylhydrazyl (DPPH), 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) and H 2 O 2 free radical scavenging activity. The in vitro antimicrobial activity of the obtained nanostructures was demonstrated against both gram negative ( Escherichia coli ) and gram positive ( Staphylococcus aureus ) bacterial genera. This study revealed antioxidant and antimicrobial properties of different structures of ZnO NPs suggesting their biomedical and industrial applications.

Oxygen vacancies (VO) as intrinsic defects play a key role in determining zinc oxide (ZnO) properties. Herein, ZnO nanorods with uniform morphology have been synthesized via hydrothermal method. The obtained nanorods appear semitransparent in SEM images indicating their electron semitransparent nature (ESN). Dye sensitized solar cells (DSSCs) studies reveal the superior electron transport property of the prepared nanorods further confirming their ESN. XPS, optical absorption, and DSSCs results suggest that the origin of ESN is the presence of an appropriate amount of VO in the ZnO nanorods. Moreover, the obtained ZnO nanorods exhibit excellent photocatalytic activity in decomposition of phenol under sunlight irradiation which is attributed to VO. Our study introduces a fundamental insight into the role of VO in inducing ESN as a new property for ZnO.

Carbon nanotubes (CNTs) possess outstanding properties that could be useful in several technological, drug delivery, and diagnostic applications. However, their unique physical and chemical properties are hindered due to their poor solubility. This article review's the different ways and means of solubility enhancement of single-wall carbon nanotubes (SWNTs). The advantages of SWNTs over the multi-walled carbon nanotubes (MWNTs) and the method of non-covalent modification for solubility enhancement has been the key interest in this review. The review also highlights a few examples of dispersant design. The review includes some interesting utility of SWNTs being wrapped with polymer especially in biological media that could mediate proper drug delivery to target cells. Further, the use of wrapped SWNTs with phospholipids, nucleic acid, and amphiphillic polymers as biosensors is of research interest. The review aims at summarizing the developments relating to wrapped SWNTs to generate further research prospects in healthcare.

Pure and alkaline metal ion (Mg, Ca, Sr, Ba) doped Cerium oxide nanostructures were successfully synthesized by hydrothermal method. The structural, optical and compositional studies of the prepared nanoparticles were undertaken by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), photoluminescence (PL), Raman, X-ray photoelectron spectroscopy (XPS) and TEM analyses. The photocatalytic activity of prepared nanoparticles was analyzed using methylene blue dye. XRD pattern reveals that the prepared nanoparticles are polycrystalline nature and there is no any by-product related peaks were observed for the doped samples. The incorporation of dopants into the CeO2 nanoparticles was confirmed through PL, Raman and XPS spectra. The enhanced photocatalytic activity for the alkaline metal doped samples was observed compared to pure cerium oxide nanoparticles.

In this work, a direct Z-scheme Cs2O–Bi2O3–ZnO heterostructure without any electron mediator is fabricated by a simple solution combustion route. Cs2O is chosen as a sensitizer to expand the light absorption range, and in addition, its conduction band minimum (CBM) and valence band maximum (VBM) positions are suitable to construct a direct Z-scheme system with ZnO and Bi2O3. Structural and elemental analyses show clear evidence for heterostructure formation. The Z-scheme charge carrier migration pathway in Cs2O–Bi2O3–ZnO is confirmed by high resolution XPS and ESR studies. The fabricated heterostructure exhibits a good ability to split water to H2 and O2 under simulated sunlight irradiation without any sacrificial agents or co-catalysts and has excellent photostability. The apparent quantum efficiency of the optimized Cs2O–Bi2O3–ZnO heterostructure reaches up to 0.92% at 420 nm. The excellent efficiency of this fabricated heterostructure is attributed to the efficient charge carrier separation, the high redox potential of the CBM and VBM benefiting from a direct Z-scheme charge carrier migration pathway and the extended light absorption range.

In this work, cerium oxide (CeO2) nanostructures have been synthesized using a sunlight-assisted combustion method from cerium nitrate hexahydrate and glycine as precursors. The synthesized sunlight-assisted cerium oxide (CeO2-SA) nanopowder has been characterized using X-ray diffraction, scanning electron microscopy, transmission electron microscope, UV–Visible spectroscopy, Raman spectroscopy, photoluminescence spectroscopy, and Nitrogen adsorption–desorption isotherm. In this method of synthesis, natural sunlight is used as energy source to ignite the reaction and the product is obtained immediately. The synthesized CeO2-SA has a fluorite-like cubic crystal structure and spongy morphology with irregular pores. It is also found that CeO2-SA possesses a smaller particle size, narrower band gap and lower recombination rate than bulk CeO2. The crystalline size of CeO2-SA nanoparticles was obtained to be 4.9 nm. The optical band gap for CeO2-SA was found to be 2.98 eV. The BET Surface area for CeO2-SA was found to be 19.7 m2/g which is 5.3 times greater than the surface area of bulk CeO2 (3.7 m2/g). Around 91% degradation of methylene blue dye (MB) is observed. Therefore, CeO2-SA exhibits higher photocatalytic efficiency towards the degradation of MB than bulk CeO2.

Retraction Note: The Editor-in-Chief has retracted this article [1] because it significantly overlaps with a previously published article from the same authors [2]. Yallappa Sangappa disagrees with this retraction. The other authors have not responded to correspondence regarding this retraction.

Silicon carbide (SiC) is recognized as a notable semiconductor because of its outstanding characteristics, for instance wide-bandgap, outstanding magnetic properties, extraordinary chemical inertness, high thermal, mechanical, optical and electronic properties, generally utilized in solid-state lighting and power electronics because of its insufficient inherent carrier and high thermal conductivity under high-power/high-temperature/high-voltage or other such harsh environments. In the present review the authors discuss SiC and their physico-chemical properties as a new generation SiC functional materials and ceramic matrix composites with the primary purpose of improving their wide range of recent applications. However, it is to be noted that the biocompatibility and other such recent applications of SiC have been seldom understood by the researchers in spite of the fact that there is an ample scope for such studies on SiC. In the present review, the authors focus on the comprehensive overview of the introduction to ceramic materials, its classifications, properties of ceramics and 3D-printed composite ceramic materials followed by state-of-art of silicon carbide along with their structure, its polytypes, properties and defects in SiC. Further multidisciplinary applications of SiC nanoarchitectures have been systematically summarized, including photocatalytic technology, membrane technology gas- chemical sensing, field emission transistors, nanoelectronics, medical implants, biosensing and so on. Finally, the future prospects and research directions of SiC nanoarchitectures are proposed.

This study describes the synthesis of silver nanoparticles (AgNPs) using aqueous silk fibroin (SF) solution obtained from Bombyx mori silk under gamma radiation environment. The obtained AgNPs were characterized using UV–visible (UV–Vis) spectroscopy, X-ray diffraction (XRD) measurements, dynamic light scattering experiment (DLS) and transmission electron microscope (TEM) images. The UV–Vis absorption spectra of the samples confirmed the formation of AgNPs by showing surface plasmon resonance (SPR) band in the range of (= 428–435 nm. The XRD study revealed metal silver with the face-centered cubic (FCC) crystal structure. DLS measurements showed the dose-dependent average size of the AgNPs. TEM images showed formed AgNPs are nearly spherical in shape with smooth edges. From this study, it was found that the increasing radiation dose increases the rate of reduction and decreases the particle size. The size of the AgNPs can be tuned by controlling the radiation dose.

We report the synthesis of TiO2 and Cobalt doped TiO2 (CoT) thin films by sol–gel process and the influence of dopant incorporation onto the structural, optical and electrical properties of the host lattice is analysed. The XRD analysis shows the reduction of crystal size with increasing Co dopant concentration. FESEM analysis confirmed the agglomeration of particles in CoT films upon Co doping. Vibrational modes of the anatase phase of TiO2 along with the weak intensity peaks for cobalt doped samples have been identified in Raman spectroscopy. The average transmittance of the films decreases with an increase in the surface roughness and decrease in the crystallinity of the films. Red shift in the energy gap is observed with the increase in the cobalt dopant concentration due to the defect state formation in the band gap. Surface roughness of the samples increases from 0.646 to 6.486 nm. Room temperature photoluminescence (PL) measurements confirmed the increase of F+ colour centres in cobalt doped films. I–V measurements indicate the ohmic behaviour of TiO2 films with the increase of resistivity from 2.707 × 103 to 7.699 × 103 Ω-cm for the samples with cobalt content. The increase in resistivity due to dopant incorporation is significant from its application point of view and is evaluated using grain boundary model. It was observed that by increasing cobalt doping level in TiO2 the surface trap density increases and implicitly the conductivity decreases.

In the present investigation, anisotropic silver nanoparticles (AgNPs) were synthesized using silk fibroin (SF) obtained from Bombyx mori silk without any reducing agent under UV-B environment. The...

In this study, a series of RE3+:YVO4 catalysts were successful synthesized by environmentally friendly mild hydrothermal and supercritical hydrothermal techniques. The rare earth-doped YVO4 photocatalysts were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, photoluminescence spectroscopy. The X-ray diffraction analysis reveals that the as-prepared YVO4 crystals are of tetragonal phase. Further, the Fourier transform infrared spectroscopy result shows the absence of OH– molecules. The photoluminescence spectroscopy curves and UV–Vis spectra suggest that the band gap energy of YVO4 is shifted to lower energy level due to doping of Nd3+ and Er3+ ions. The catalytic activities of the as-prepared RE3+:YVO4 samples were tested for the photodegradation of amaranth aqueous dye solution under sunlight irradiation. Remarkably, the rare earth-doped YVO4 nanocrystal sample showed outstanding photocatalytic degradation activities than undoped YVO4 nanocrystal sample with good reusability. Under full spectrum irradiation, the as-prepared Nd3+-doped YVO4 nanocrystals exhibited about 83% degradation efficiency. The apparent rate constant k for as-prepared Nd3+-doped YVO4 nanocrystals with 50 mg of photocatalyst exhibits highest k value (0.32 min−1), which is 2.9% higher than pure YVO4 nanocrystals (0.11 min−1).

The development of heterostructured semiconductor photocatalysts makes a noteworthy advancement in environmental purification technology. In this work, a novel heterostructured Bi2O3−CeO2−ZnO, fabricated by a combination of microwave-assisted hydrothermal and thermal decomposition methods, showed an enhanced photocatalytic activity for Rhodamine B (RhB) degradation under sunlight, as compared to pristine ZnO, Bi2O3, CeO2, and commercial Degussa TiO2-P25. The obtained products were thoroughly characterized by various techniques including X- ray powder diffraction (PXRD), field emission scanning electron microscopy (FE-SEM), elemental color mapping, energy-dispersive X-ray spectroscopy (EDAX), Raman spectrometry, Fourier transform infrared (FT-IR) spectroscopy, UV–visible diffuse reflectance spectroscopy (UV–vis DRS), and photoluminescence (PL) spectroscopy. PXRD analysis reveals that the heterostructure has the monoclinic lattice phase of α-Bi2O3, the cubic phase of CeO2 and the hexagonal wurtzite phase of ZnO. FE-SEM images show that Bi2O3−CeO2−ZnO has an ordered mixture of nanorod and nanochain structures. EDAX, elemental color mapping, Raman and FT-IR analyses confirm the successful formation of the heterostructured Bi2O3−CeO2−ZnO. The UV–Vis DRS results demonstrate that Bi2O3−CeO2−ZnO exhibits wide visible-light photoabsorption in 400–780 nm range. Moreover, the reduction in PL intensity of the heterostructured Bi2O3−CeO2−ZnO, when compared to the pristine Bi2O3, CeO2, and ZnO, indicates enhanced charge separation. The study on the mechanism displayed that the improved photocatalytic activity of Bi2O3−CeO2−ZnO could be attributed to (1) the efficient separation of photoinduced electrons and holes of the photocatalysts, caused by the vectorial transfer of electrons and holes among ZnO, CeO2 and Bi2O3, and (2) the wide visible-light photoabsorption range. This study introduces a new class of promising sunlight-driven photocatalysts.

The effect of gamma irradiation on hydrothermally synthesized BaTiO3 nanoparticles has been investigated. Gamma irradiation was carried out at room temperature from 0, 50, 100, 150, 200 kGy to a maximum dose up to 250 kGy, source being 60Co gamma radiations. The structure, size and chemical changes of the BaTiO3 were studied using X-ray diffraction, Fourier-transform infrared spectrophotometry (FTIR) techniques and scanning electron microscopy (SEM). The optical band gap has been computed by UV–Visible spectroscopy data. From the results obtained, it is evident that the gamma irradiation increases the crystallinity, whereas the particle size of BaTiO3 nanoparticles is altered. UV–Visible spectroscopy shows a noticeable change in the energy band gap due to gamma irradiation. Significant changes in anharmonicity constant computed using FTIR data due to irradiation has been observed. SEM shows the size and deviation from uniformity of particles.

In the present work, assembly and fabrication of nano-sized Zinc Sulphide (ZnS) particles grown on Graphene Oxide (GO) by the facile sol-gel method treated with microwave irradiation and assisted by hydrothermal processing. The production of high quality and self-assembled ZnS-RGO hybrid nanocomposites without the use of any surfactants/templates are been reported. Synthesis, interaction, kinetics and mechanism of hybrid ZnS-RGO composite are been studied. The results show that the photodegradation efficiency of brilliant blue under UV light irradiation for hybrid nanocomposite was better than GO and ZnS are reported. The photocatalytic activity strongly depended on the coverage of ZnS nanoparticles on the surface of graphene oxide sheets and the synergic adsorptive interaction between ZnS and GO. The enhancements of photo-catalysts activity are attributed to high migration efficiency of photoinduced electrons and inhibited charge carrier's recombination due to electronic communication between ZnS and GO. The nanocomposite having large surface area and microporous in nature played a vital role in absorptive activity are confirmed by BET surface area measurement. In addition, photoluminescence spectra of nanohybrids of ZnS-RGO composites displayed the surface plasma resonance and fluorescence quenching property. XRD, FT-IR, Raman spectroscopy, UV–visible spectroscopy, SEM with EDS, XPS, TEM and HR-TEM confirmed the structure and morphology of nanocomposite.

The orthorhombic perovskite, Gadolinium aluminum oxide (GdAlO3, GAP) material was successfully prepared by hydrothermal supercritical fluid method using co-precipitated gel of GAP. All experiments were carried out in the pressure and temperature ranges of 100–150 MPa and 180–650 °C respectively. The as-prepared GAP samples were systematically characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), X-ray spectroscopy (EDS), thermo gravimetry (TGA) and differential thermo gravimetry analysis (DTA). The XRD profile confirms fully crystalline and orthorhombic nature of as-prepared materials, which is well correlated to the reported results. The SEM studies reveal that the GAP materials synthesized at 650 °C/150 MPa for 92 hrs possesses polycrystalline nature with average particle size in the range of 5–20 µm. The DTA shows a crystallization peak at 361 °C at this temperature the agglomerated GAP gel starts to crystallize into polycrystalline GAP materials. When compared with other methods, like sol-gel and solid-state reactions our crystallization temperature is very much lower and feasible. This work not only demonstrates a simple way to fabricate GAP polycrystalline materials from co-precipitated gels but also shows a possible utilization of same technique for synthesis of other high temperature materials.

Zinc oxide (ZnO) nanoflowers have huge potential for various applications. However, the growth mechanism of ZnO nanoflowers is still under debate despite various growth mechanisms having been proposed. The aim of this study is to investigate the growth mechanism of different morphologies in a single sample; hopefully, this might help to understand the exact growth mechanism of ZnO nanoflowers. Herein, two models are proposed: (I) the growth mechanism of different morphologies (shapes) in a single sample; and (II) the growth mechanism of different sized ZnO flowers in a single sample. The present work also investigates the mechanism for how morphology assists in tuning the properties of nanomaterials, which is still unclear to date. New insight into the relationship between morphology and native defects has been introduced in this work. XPS, photoluminescence, and FT-IR analyses reveal the presence of oxygen vacancy defects in the structures of the materials prepared, with respect to their morphology. These defects act as self-dopants. Therefore, a change in their concentration results in tuning the band gap and thereby the photocatalytic activity.

Thymus vulgaris leaf extract was used as a stabilizer and reducing agent in the green, facile, and biomimetic hydrothermal decomposition reaction for the fabrication of zinc oxide-silver nanocomposites (ZnO-Ag NCs). The nanocomposite (NC) as an active agent was integrated into poly(3-hydroxybutyrate-co-3-hydroxyvalerate)-chitosan (PHBV-CS) in a highly precise ratio of solvent mixture by ultrasonication without the aid of any coupling agent to fabricate the novel degradable biopolymer (BP) nanocomposite via solvent casting method to enhance the mechanical properties and antimicrobial activity and with the lowest immigration rate to improve the shelf life of poultry items. The ZnO-Ag NCs as a nanoactive agent in the food packaging preserved food safety by controlling its spoilage. The morphology, physical, mechanical, barrier, antibacterial, and migration properties of the nanocrystals were assessed via several characterization methods to show the enhancement of the prepared polymer in various aspects of properties. The NCs BP were used for potential sensory evaluation of chicken breast refrigerated over a period of 15 days. The data demonstrated that these bio-based nanocomposites show great antimicrobial activity that offers perspectives for the replacement of traditional petrochemical-based polymers currently used for food packaging of poultry items.

Rational design of photocatalyst with wide solar-spectrum absorption, negligible electron-hole recombination, and maximized redox potential is an essential prerequisite for achieving commercial-scale photocatalytic H2 production. This contribution combines surface plasmon resonance and Z-scheme charge transport in a single photocatalyst (Ag-ZnO-CeO2 heterostructure) aiming to improve its performance for photocatalytic H2 production. The Ag-ZnO-CeO2 heterostructure is fabricated via sunlight-driven combustion and deposition approaches. The successful construction is confirmed by several characterization techniques. The Z-scheme configuration is verified by in situ irradiated XPS and ESR analyses. Ag plays dual rules as an electron mediator to facilitate the Z-scheme charge transport and plasmonic material to maximize the light absorption in the visible region. The designed photocatalyst exhibits significantly enhanced photocatalytic activity for H2 production (18345 μmol h−1 g−1) under simulated sunlight irradiation. This work offers the opportunity of constructing efficient Z-scheme photocatalyst from wide bandgap semiconductors with full-visible light response, suppressed electron-hole recombination, and optimized redox potential.

Graphene oxide (GO) is sp2 bonded carbonaceous antibacterial substance acting by surface contact. Here, we assayed antibacterial efficiency of GO against two nosocomial pathogens, Staphylococcus au...

(2E)-1-(anthracen-9-yl)-3-(4-chlorophenyl)prop-2-en-1-ones and (2E)-1-(anthracen-9-yl)-3-(4-nitrophenyl) prop-2-en-1-ones crystallize in the monoclinic crystal system with space group P2 1 /c. Single-crystal X-ray diffraction data for both the compounds were collected on an X’Calibur CCD area detector diffractometer (Oxford Diffraction) using MoKa radiation (λ= 0.7107 A) at 293(2) K. The crystal structures were solved by direct methods and refined by full-matrix least-square procedures to a final R value of 0.0468 [I] and 0.0486 [II]. The crystal structures as elucidated by X-ray diffraction methods show the presence of a few intermolecular interactions, and the nature and energetics associated with these interactions have been characterized using PIXEL software.

In the present work, magnetite (Fe 3 O 4 , avg. ~70 nm) synthesis employing Azadirachta indica (neem) leaf extract is reported originally using hydrothermal conditions and the results obtained were compared with that of D -glucose. Fourier transform infrared spectroscopy confirms the presence of polysaccharides and proteins in the extract which act as both surfactants and reducing agents, aided the formation of magnetite nanostructures. Authors also reported the selective doping of Zn, Cu and Co on nickel ferrite for the enhancement of adsorptive dye removal property, adopting and investigating the use of eloquent one-step green hydrothermal approach ( T =180 °C, t =4 h, pH=12) with sodium dodecyl sulfate as surfactant. X-ray diffraction studies reveal that all the materials synthesized are isometric spinel structures and furthermore, morphological evidences using scanning electron microscopy are accounted. Adsorptive dye removal ability of synthesized materials was investigated using trypan blue as a probe. It was evident from the results that magnetite using neem extract showed enhanced adsorption ability (75%) than that of D -glucose (62%). Also, exponential increase in dye removal efficiency from 55% to 81% due to the presence of copper in nickel ferrite was duly noted.

One of the most recognized and widely used treatment modality in cancer is radiation therapy which depends on the radiosensitivity of tumour tissue. Over the past few years there has been lot of interest in the use of formulations to enhance radiotherapeutic effects, especially using metallic (mainly gold) based nanoparticles. Our goal here is to fabricate nanoparticles (NPs) that can be delivered to tumor tissue to increase its radiosensitivity. This would increase efficiency of radiation absorption by the tumor tissue and reduce radiation doses delivered during radiotherapy. This could potentially decrease radiation exposure related side effects to patients. We have achieved this by synthesizing nanoparticles of high Z elements such as gold, silver and a more efficient bimetallic silver-gold size ranging from 3nm to 72nm using chemical reduction and hydrothermal method. The synthesized metallic nanoparticles were characterised using Ultraviolet (UV)-Visible Spectroscopy, Fluorescence spectroscopy and Dynamic Light Scattering. The metallic nanoparticles showed radiosensitizing activity in colloidal form by absorbing radiations when irradiated by 60Co source which emits two gamma rays of energy 1173keV and 1332keV Based on our results, we are of the opinion that such radio-sensitizing agent if injected into the tumour tissue would increase radiation absorption and enhance treatment effect with lower therapeutic radiation dosage.

The colloidal silver nanoparticles (AgNPs) were synthesized in situ under white light at room temperature using aqueous silk fibroin (SF) obtained from Bombyxmori silk. The UV-visible spectroscopy revealed the formation of AgNPs by showing a typical surface Plasmon resonance (SPR) band at 422 nm from the UV-visible spectra. The transmission electron microscope (TEM) images show that the formed nanoparticles were spherical in shape with smooth surfaces. The particle diameter was around 35-40 nm. Further the X-ray diffraction (XRD) analysis confirms the nanocrystalline phase of silver with face centered cubic (FCC) crystal structure. The biogenic silver nanoparticles exhibited significant antibacterial activity against human bacterial pathogens Bacillus subtilis, Staphylococcus aureus, Salmonella typhi and Escherichia coli.

A series of PVA/CMC polymer composite films with different amounts of NiCuZnFe2O4 (nickel–copper–zinc–ferrite) was prepared by means of solution-casting technique. These films were characterised using various techniques like X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), ultraviolet–visible spectroscopy (UV–visible) and AC electrical conductivity measurements. Recorded XRD pattern at room temperature shows an increase in amorphousity of the matrix with concentration of NiCuZnFe2O4 nanoferrite. Microstructural parameters were computed using an in-house program employing XRD data. UV–visible spectra show that the optical absorption of the PVA/CMC nanocomposite films in the UV region is quite high. FTIR spectra show the stretching of the major vibration bands associated with organic–inorganic chemical groups present in the nanoferrite-doped polymer blends. Measured AC electrical conductivity of prepared samples shows that the added nanoferrite does increase the ionic conductivity at...

In the present work, a simple and systematic approach for the reduction of graphene oxide (GO), that converts to chemically modified graphene at low temperature (T = 200 °C) using ultrasonication assisted mild solvothermal method without the use of any surfactants/stabilizers has been employed. Graphene Oxide sheets are reduced in polar and non-polar organic liquid media under ultrasonication and thermal process conditions, which aids in active high yield chemically modified few layers graphene sheets with tunable C/O ratios dependent on the boiling point of the solvent. The reaction time, temperature, auto generated pressure in the reaction vessel and the reducing power of the solvents influenced the extent of reduction of graphene oxide sheets to modified graphene sheets. This study examined the dispersion behavior of graphene oxide in a polar solvent and non-polar, as well as the differences in the behavior in various solvents related to the solubility parameter. The chemically modified graphene produces a flexible morphology with a large surface area and micro porous distribution resulting in “sheets/flakes like” materials generated by very simple ultrasonication and thermal exfoliation of the reduced graphene oxide sheets in a wide variety of organic solvent.

Study on the effect of microwave irradiation on structural and physical properties of bivoltine silk fibroin films were carried out. This characteristic analysis was done using X-Ray Diffraction, FT-IR spectroscopy and SEM imaging. The study reveals that the microwave irradiations on silk film for various dosage intervals enhances the cross-linkage between the silk chains and helps in gaining its structure back. This regeneration of silk fibroin films make them more brittle in nature. Further, such cross-linking isolates the residual lithium ion in the matrix and this is evident by the results of analytical studies carried out.

Liquid crystals are anisotropic materials with a distinct phase of matter observed between the crystalline (solid) and isotropic (liquid) states. The introduction of heteroatoms can result in large changes in the corresponding liquid-crystalline phases and in the physical properties of the observed phases. In present work, we synthesized new array of heterocyclic compounds with various alkoxy substituents using p-hydroxy benzaldehyde as the precursor, these were taken to next step for alkylation with different alkyl bromides (C n H 2n+1 Br) where n=3,4,5,6,7,8,10,12,14,16,18 to form O -alkylated benzaldehyde and finally they were cyclised to reach our goal of synthesizing various derivatives of Isoxazoline.

Zinc Oxide-Graphene Oxide (ZnO-GO) nanocomposite have been fabricated by facile, low-temperature wet chemical process assisted with microwave irradiation and used for the photo degradation of Brilliant Blue under UV-Vis light radiation. The in-situ formed ZnO nano wires were randomly decorated on the surfaces and the edges of graphene oxide sheets, simultaneously reduced directly capable of forming the graphene sheets. The lattice constants and band gap energy of ZnO has been altered compared with pure nano-sized ZnO particles, which are confirmed by XRD. The graphene oxide sheets were anchored/tailored with ZnO particles and the photo degradation of Brilliant Blue were performed under UV-Vis light radiations. The results shows that graphene oxide hybridized with ZnO could produce an efficient photo-catalytic activity and the degree of photocatalytic activity enhancement strongly depends on bonding of ZnO nanowires and GO. The enhancements of photocurrent and photo catalytic activity attributed to the suppression of charge carrier's recombination resulting from the interaction between ZnO and GO. The optical, structural and morphology of the pure ZnO and ZnO-GO nanostructures were systematically studied by X-ray diffraction (XRD), Fourier Transformation Infrared spectroscopy (FTIR), UV-Vis spectroscopy, Raman spectroscopy, Photoluminescence spectroscopy, Energy dispersive spectroscopy (EDS), field emission scanning electron microscopy (FESEM).

Surface plasmon resonance effect, Fenton’s reaction, plant extract, and nanoparticles have all proven to be efficient in killing or reducing the activity of numerous microorganisms. To study the synergetic effects among these key parameters, Ag-ZnO-Fe3O4 nanocomposites have been synthesized via solution combustion approach in the presence of aqueous extract of Thymus vulgaris leaves. The successful construction of Ag-ZnO-Fe3O4 nanocomposite and its purity were confirmed by X-ray diffraction, X-ray photoelectron spectra, and energy dispersive X-Ray spectroscopy analyses. Dynamic light scattering and transmission electron microscopy measurements showed that the size of the obtained particles is in the nanoscale. The synthesized nanocomposite showed broad inhibition against the selected bacteria and yeast under LED light. UV–vis absorption measurement showed that the heterostructure exhibits broad plasmonic peak centered around 434 nm. Hot charge carriers are generated in Ag under LED light illumination and separated through Ag-ZnO heterojunction resulting in the production of a considerable amount of OH radicals as confirmed by ESR analysis. Moreover, Ag acts as H2O2 donator and photogenerated electrons provider for the Fenton’s reaction, resulting in the generation of much more OH radicals. Therefore, Ag-ZnO-Fe3O4 nanocomposite shows improved microbial activity under LED light illumination.

Due to unique electron transport properties, nanostructured catalysts with certain morphology, such as nanotube, nanosheet and nanorods, have shown outstanding photocatalytic performance. Herein, preparation of ternary photocatalytic architecture is demonstrated using a facile microwave-assisted hydrothermal method. The as-prepared ternary photocatalyst (denoted as Bi2S3/MoS2/TiO2) comprises bismuth sulfide (Bi2S3) nanorods, molybdenum sulfide (MoS2) nanosheets, and titanium dioxide (TiO2) nanotubes. The photocatalytic performance of the as-prepared nanocomposite is evaluated by monitoring water splitting and dye degradation. The results show that the Bi2S3/MoS2/TiO2 exhibits stable and highly efficient photocatalytic hydrogen production under visible light, and photocatalytic degradation of methylene blue (MB) under sunlight. The photocatalytic performance of Bi2S3/MoS2/TiO2 is much better than that of TiO2, MoS2, or Bi2S3. The improved performance is correlated to the high surface area and the formation of the double Z-scheme heterostructure, which together render abundant catalytic sites and efficient charge separation with strong redox capability. Additionally, X-ray photoelectron spectroscopy and electron spin resonance spectroscopies, combined with reactive species trapping experiments, confirm that the surface charge transport in Bi2S3/MoS2/TiO2 occurs through the double Z-scheme approach. This work paves the way for designing more photocatalytic systems with double Z-scheme for high efficiency and wide practical applications.

The crystallographic study of 2,2’-((4-bromophenyl)methylene)bis(3-hydroxy-5,5-dimethylcyclohex-2-en-1-one) reveals that the compound crystallizes in the centrosymmetric space group $$P2_{1}/c$$ . In the solid state, the structure of the title compound exhibits two strong intramolecular $$\hbox {O}{-}\hbox {H}\cdots \hbox { O}$$ hydrogen bonding interactions. Further, molecules of the title compound are self-assembled by weak intermolecular $$\hbox {C}{-}\hbox {H}\cdots \hbox {O}, \pi \cdots \pi $$ and $$\hbox {H}\cdots \hbox { H}$$ and $$\hbox {C}{-}\hbox {H}\cdots \hbox { Br}$$ contacts. Various intermolecular interaction that exist in the crystal structure and their energetics are quantified using PIXEL, DFT and QTAIM analyses. Six different motifs are identified from the PIXEL calculation. Lattice energy calculation suggests that the dispersion energy has the highest contribution for the crystal formation. The relative contributions of various intermolecular contacts in the title compound and its closely related analogs are evaluated using Hirshfeld surface analysis and the decomposed fingerprint plots. The common packing features exist between the title compound and its related analogs are identified. The quantitative molecular electrostatic potential surface diagram depicts the potential binding sites which are in good agreement with the crystal structure of the title compound. The structures of title compound in gas and solvent phases are compared with the experimental structure and reveals that they are superimposed very well. The vibrational modes of the monomer and four most stabilized dimers are characterized using both the experimental and DFT calculations. The UV-Vis spectrum is calculated using time dependent-DFT (TD-DFT) method and compared with experimental spectrum. The results indicate that the calculated energy of absorbance and oscillator strength correlate well with the experimental data. SYNOPSIS. Synthesis and crystal structure analysis of 2,2’-((4-bromophenyl)methylene) bis(3-hydroxy-5,5-dimethylcyclohex-2-en-1-one) are reported. Molecules of this compound are self-assembled by intermolecular $$\hbox {C}{-}\hbox {H}\cdots \hbox {O}$$ , $$\pi \cdots \pi $$ and $$\hbox {H}\cdots \hbox { H}$$ and $$\hbox {C}{-}\hbox {H}\cdots \hbox { Br}$$ interactions. The relative contributions of various intermolecular interactions in the bromo derivative and its closely related analogs are quantified using theoretical approaches.

The synthesis of metal nanoparticles by eco-friendly procedures is a need of nanotechnology today. One such important approach which shows enormous potential is based on the in situ synthesis of gold nanoparticles (AuNPs) using silk fibroin (SF) extracted from Bombyx mori silk. The UV-visible absorption spectra confirmed the reduction of gold ions to gold nanoparticles by showing characteristic surface Plasmon resonance (SPR) in the wavelength range λ = 530-545 nm. The X-ray diffraction (XRD) measurement study suggests the synthesized metal gold nanoparticles are FCC crystal structure. Further, the transmission electron microscopy (TEM) images showed that the formed AuNPs are spherical, rod, hexagonal and triangle in shapes.

This review is an audit of various Carbon fibers (CF) surface modification techniques that have been attempted and which produced results with an enhancement in the interfacial characteristics of CFRP systems. An introduction to the CF surface morphology, various techniques of modifications, their results and challenges are discussed here. CFs are emerging as the most promising materials for designing many technologically significant materials for current and future generations. In order to extract all the physic-mechanical properties of CF, it is essential to modulate a suitable environment through which good interfacial relation is achieved between the CF and the matrix. The interface has the utmost significance in composites and hybrid materials since tension at the interface can result in a deterioration of the fundamental properties. This review is aimed to provide a detailed understanding of the CF structure, its possible ways of modification, and the influence of interfacial compatibility in physic-mechanical and tribological properties. Both physical and chemical modifications are illustrated with specific examples, in addition to the characterization methods. Overall, this article provides key information about the CF based composite fabrication and their many applications in aerospace and electronics- where light weight and excellent mechanical strength are required.

The synthesis of metal nanoparticales by environmentally friendly processes is an important aspect of nanotechnology today. One such approach that shows immense potential is based on the in situ synthesis of gold nanoparticles (AuNPs) using naturally available materials such as aqueous silk fibroin (SF) obtained from Bombyx mori silk. The UV-visible absorption study revealed the formation of AuNPs by showing characteristic surface plasmon resonance (SPR) band at 525 nm. The X-ray diffraction (XRD) analysis study suggests the synthesized gold nanoparticles are FCC crystal structure. The transmission electron microscopy (TEM) images showed that the formed AuNPs are spherical in shape with smooth edges.The synthesis of metal nanoparticales by environmentally friendly processes is an important aspect of nanotechnology today. One such approach that shows immense potential is based on the in situ synthesis of gold nanoparticles (AuNPs) using naturally available materials such as aqueous silk fibroin (SF) obtained from Bombyx mori silk. The UV-visible absorption study revealed the formation of AuNPs by showing characteristic surface plasmon resonance (SPR) band at 525 nm. The X-ray diffraction (XRD) analysis study suggests the synthesized gold nanoparticles are FCC crystal structure. The transmission electron microscopy (TEM) images showed that the formed AuNPs are spherical in shape with smooth edges.