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Due to the characteristic emission of phosphors, phosphor-converted LEDs have been employed to provide the requisite light sources for indoor plant growth in the optical agricultural industry. Herein, we prepared a series of Mn2+ co-doped NaSrB5O9:Dy3+ phosphors via a solid-state reaction method. These phosphors have significant three-band emissions at 467 nm (blue region), 606 nm (orange region), and 765 nm (far-red region), ascribed to the 4F9/2-6H15/2 and 4F9/2-6H13/2 transitions of the Dy3+ ions and the 4T1g(G)-6A1g(S) spin-forbidden transition of the Mn2+ ions, respectively, when excited by light of 376 nm (near-UV region). The co-dopant in the host material facilitates tunable photoluminescence (PL) due to energy transfer from the Dy3+ ions to the Mn2+ ions. The three emission peaks from the prepared phosphors well match with the absorption spectra of the photosynthesis pigments of plants, chlorophyll and phytochrome, which can absorb blue (400–500 nm), orange-red (550–700 nm), and infrared (IR) radiation, indicating that these phosphors have potential applications in the fabrication of plant-growth LEDs. Prior to the PL studies, the structure of the phosphors was determined by X-ray diffraction, refined by Rietveld method and chemically quantified by X-ray photoelectron spectroscopy.

Curcumin is a natural polyphenol obtained from Curcuma longa which has gained much attention in medical and scientific fields and is known for its wide range of therapeutic applications. But the natural herb mixtures with high subatomic sizes have low retention limits which does not permit the restorative medication to cross the lipid membranes, subsequently bringing about low bioavailability with confined proficiency. Nanobiotechnology has overcome the drawbacks of curcumin delivery to its targeted site through the use of antioxidant-rich, biodegradable SLNs as drug delivery vehicle with specificity and expanded bioavailability that will encourage the dynamic release of therapeutic ingredients into the body. Herein, optimized curcumin-loaded SLNs (CuSLNs) were developed. The morphological analysis of SEM has shown the average particle size was found to be in the range of 71–112 nm. The physicochemical characteristics of optimized CuSLNs were particle size of 106 nm, zeta potential of − 54 mV, polydispersity index of 0.429 which have confirmed the nanoparticle stability. The FTIR, DSC, and XRD results have suggested the lipids are compatible and confirmed the complete solubilization of curcumin in the lipid phase. Encapsulation efficiency and drug loading capacity of optimized formulation were 88.22 and 13.13, respectively. In vitro release studies have shown the controlled drug release rate of 88% compared with free curcumin and 81% of in vitro antioxidant activity which is compared with the ascorbic acid. The studies confirmed that the formulation of CuSLNs is a promising drug delivery system with controlled drug release, improved bioavailability with good stability.

Environmental issues: global warming, organic pollution, CO2 emission, energy shortage, and fossil fuel depletion have become severe threats to the future development of humans. In this context, hydrogen production from water using solar light by photocatalytic/photoelectrochemical technologies, which results in zero CO2 emission, has received considerable attention due to the abundance of solar radiation and water. Herein, a single-step thermal decomposition procedure to produce carbon-doped SnO2 nanostructures (C–SnO2) for photocatalytic applications is proposed. The visible-light-driven photocatalytic performance of the as-prepared materials is evaluated by photocatalytic hydrogen generation experiments. The bandgaps of the photocatalysts are determined by ultraviolet–visible diffused reflectance spectroscopy. The crystallinity, morphological features (size and shape), and chemical composition and elemental oxidation states of the samples are investigated by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy. The proposed simple thermal decomposition method has significant potential for producing nanostructures for metal-free photocatalysis.

Strategic way of regulating and changing the morphological structures of metal oxides always direct to be contributed with different electrochemical properties for redox reactions in energy storage systems. Here in, we have engineered the morphologically controlled zinc cobaltite and zinc oxide (ZnO/ZnCo2O4) composite via an in situ solvothermal route. By varying the reaction time of the solvothermal synthesis, the morphology of the composite has significantly been transformed from Chrysanthemum to Marigold -flower like ZnO/ZnCo2O4 composite. The morphological variations are identified by scanning electron microscopy (SEM) images. The two phases of composites are quantified by refinement of X-ray diffraction data and is endorsed by X-ray photoelectron spectroscopy. By using these two analyses, the non-stoichiometry of the elements (Zn, Co and O) have quantified. Two composites not only demonstrate different physico-chemical properties but also contribute different electrochemical properties. Low reaction time synthesized ZnO/ZnCo2O4 composite has shown higher specific capacitance than the higher reaction time synthesized composite. The ZnO/ZnCo2O4 composite indicates specific capacitance of 705.1 F g−1 (at 0.3 A g−1), which is due to the Co-rich, higher surface area and lower charge transfer resistance of the low reaction time synthesized composite against the counterpart.

The present work reports on the highly efficient microwave assisted Suzuki coupling reaction for obtaining pyromellitic diimide based symmetrical small molecules with donor-acceptor-donor (D-A-D) configuration. Electron rich bithiophene is employed as a donor and alkyl substituted pyromellitic diimide units are explored as acceptors to get the desired small molecules. In order to study the relation between chemical structures and material properties, the prepared compounds were characterized in detail using absorption spectroscopy, cyclic voltammetry and thermograviometric analysis. The compounds exhibited good thermal stabilities with high decomposition temperature. Photophysical investigations of the newly synthesized pyromellitic diimide based small molecules, suggests these materials as potential candidates for organic electronic applications.

Presently, photocatalytic hydrogen generation from water splitting has attractive limelight research towards accomplish green globalization (zero CO2 emission) and considered as fuel source of the future due to their high energy content. Heterogeneous semiconductor/metal hybrid structures are receiving increased attention because of their advanced optical, electrical, and catalytic properties, which result from synergic effects. Herein, we developed an approach to fabricate interwoven Cu core nanowires (Cu NWs) decorated with different weight of ZnO nanorods (ZnO NRs) for photocatalytic applications. The bandgaps of the prepared hybrid structures were calculated by using UV–Vis spectra, their crystalline nature was examined with XRD, the morphology of nanostructures was studied by SEM, and their elemental composition and oxidation states were analyzed by XPS. Their photocatalytic activity was investigated for the production of hydrogen and dye (Rhodamine B) degradation. The Cu NW–ZnO NR hetero-assemblies were found to exhibit high photocatalytic properties, due to the synergetic effects of the unique semiconductor/metal heterojunction. The optimized CuZ2 composite exhibited 7.2 times H2-production and 6.2 times degradation of RhB greater than pure ZnO, respectively. Moreover, ZnO-nanorods can harvest solar light to generate photoelectrons, with subsequent electron transfer through the Cu NWs that might favor photocatalytic processes for many energy applications.

Continuously increasing energy demand and growing concern about energy resources has attracted much research in the field of clean and sustainable energy sources. In this context, zero-emission fuels are required for energy production to reduce the usage of fossil fuel resources. Here, we present the synthesis of Pd-Ag-decorated reduced graphene oxide (rGO) nanostructures using a green chemical approach with stevia extract for hydrogen production and antibacterial studies under light irradiation. Moreover, bimetallic nanostructures are potentially lime lighted due to their synergetic effect in both scientific and technical aspects. Structural characteristics such as crystal structure and morphological features of the synthesized nanostructures were analyzed using X-ray diffraction and transmission electron microscopy. Analysis of elemental composition and oxidation states was carried out by X-ray photoelectron spectroscopy. Optical characteristics of the biosynthesized nanostructures were obtained by UV-Vis absorption spectroscopy, and Fourier transform infrared spectroscopy was used to investigate possible functional groups that act as reducing and capping agents. The antimicrobial activity of the biosynthesized Pd-Ag-decorated rGO nanostructures was excellent, inactivating 96% of Escherichia coli cells during experiments over 150 min under visible light irradiation. Hence, these biosynthesized Pd-Ag-decorated rGO nanostructures can be utilized for alternative nanomaterial-based drug development in the future.

Admirable studies have been established on the utilization of ligand-materials as bimetallic nanoparticles in the field of nanoscience and biotechnology. UV-Vis, XRD, HR-TEM, STEM-HAADF, EDS, FTIR, and DPPH analyses characterized the optical, structural, compositional morphological, and antioxidant properties of synthesized Cu-Ag nanostructures. The spectrum of UV-Vis exhibited absorption bands at 590 and 413 nm, which reflects the surface plasmon resonance of copper-silver nanostructures. Herein, our exploration of alkylamine stabilized copper/silver nanostructures while using hexadecylamine as capping material and their primary biomedical investigation on antimicrobial and antioxidant studies is reported. Cu-Ag bimetallic nanostructures were more effective against gram-negative bacteria E. coli and Klebsiella when compared to gram-positive bacteria. The antioxidant activity of Cu-Ag nanoparticles was comparable with Ascorbic acid.

With the rapid improvement of the global economy, the role of energy has become even more vital in the 21st century. In this regard, energy storage/conversion devices have become a major, worldwide research focus. In response to this, we have prepared two-dimensional (2D)-hierarchical sheet-like ZnCo2O4 microstructures for supercapacitor applications using a simple hydrothermal method. The 2D-hierarchical sheet-like morphologies with large surface area and smaller thickness enhanced the contact area of active material with the electrolyte, which increased the utilization rate. We investigated the electrochemical performance of sheet-like ZnCo2O4 microstructures while using Cyclic voltammetry (CV), Galvanostatic charge-discharge (GCD), and Electrochemical impedance spectroscopy (EIS) analysis. The electrochemical results demonstrated that the ZnCo2O4 electrode possesses 16.13 mF cm&minus, 2 of areal capacitance at 10 &micro, A cm&minus, 2 of current density and outstanding cycling performance (170% of capacitance is retained after 1000 cycles at 500 &micro, 2). The high areal capacitance and outstanding cycling performance due to the unique sheet-like morphology of the ZnCo2O4 electrode makes it an excellent candidate for supercapacitor applications.

Bimetallic nanomaterials have potential catalytic behaviour in hydrogenation, clean- energy production, catalysis and sensors due to their great stability, loftier activity unique electrical and chemical properties. Herein, we prepared Pd Ag bimetallic nanoparticles synthesized by using fungal extracted aqueous method, which is environmentally friendly cost-effective and simple procedure. The fabricated Pd Ag bimetallic nanoparticles were investigated by small area electron diffraction (SAED), transmission electron microscopy (TEM) X-ray photoelectron spectroscopy (XPS) and energy dispersive X-ray spectroscopy (EDX) analysis. The electrochemical response of uric acid (UA) at Pd-Ag/CPE was studied in 0.1 M phosphate buffer solution at various pH, concentration and scan rate was investigated. Compare to Bare CPE, the Pd Ag nanocomposite modified electrode displayed the highest electrocatalytic activity for the detection of UA A linear response in the range of 4.69–273 nM with remarkable detection limit of 5.543 nM (CDL = 3ϭ/M) and quantification limit of 16.64 nM (CQL = 10ϭ/M) was obtained. The established nanoparticles (Pd Ag) embedded with carbon paste electrode (Pd-Ag/CPE) makes a good analytical tool for the sensing of UA in the biological and pharmaceutical samples.

A flexible transparent conductive electrode (TCE) with silver nanowires (AgNWs) is an essential component in flexible optoelectronic devices. Considerable efforts have been made to improve the transmittance and sheet resistance of AgNWs TCE for large area applications. However, long-term usages of AgNW TCEs are limited by their poor thermal and chemical stabilities under different atmospheric conditions. In this work, we propose to improve the opto-electrical properties by fabricating AgNWs layer on a metal mesh (MM) polyethyleneterephthalate (PET) substrate (AgNW/MM/PET). A bilayer structure of the AgNW/MM/PET was fabricated by bar coating, and it exhibited excellent opto-electrical properties with a transmittance of 90.3% and a sheet resistance of 0.745 Ω/sq. In addition, the fabricated AgNW/MM/PET showed more stable electrical performances than mono layer TCEs with AgNWs or metal mesh on PET under various environmental conditions, such as light, temperature, and humidity. The AgNW/MM/PET electrodes with excellent opto-electrical properties could be a possible replacement for indium tin oxide for large area flexible optoelectronic applications.

Researchers have tried to further advance the utilization of bimetallic nanoparticles in the field of catalysis due to their high stability, reusability, superior activity, and unique electronic and optical properties as compared with mono-metallic nanomaterials. Moreover, due to the lack of availability and economic viability of mono-metallic nanoparticles, it is necessary to produce highly active ultra-small bimetallic nanoparticles for industrial applications. Cu/Pd bimetallic nanoparticles are synthesized by using a mild hydrothermal one-pot method involving an aqueous solution with hexadecylamine as a capping agent for hydrogenation of aromatic nitro compounds. The synthesized bimetallic Cu/Pd nanoparticles form a cluster of 5 ± 3 nm bimetallic particles, and Cu/Pd clusters have been measured to perform the catalytic performance of hydrogenation of 4-nitrophenol, methylene blue, and methyl orange. Cu/Pd nanoparticles have been treated with lactic acid to remove the residual capping agent on the surface, which results in two times better catalytic relay effect between aromatic nitro compounds and NaBH4 in aqueous media than Cu/Pd without lactic acid treatment.

Over the past few decades, increasing attention has been focused on overcoming the scarcity of fresh water resources, with the rapid effluents of dyes from modern chemical industries causing issues in photosynthetic activity of aquatic organisms. In the process of recycling wastewater, the degradation of dye pollutants such as 4-nitrophenol, methylene blue, and methyl orange has become more crucial. Noble metal (silver, gold, palladium, and platinum) materials have significant potential applications in the areas of water purification, conversion of automobile exhaust emissions, and catalysis. Ultra-small alkylamine-capped palladium nanoparticles (APd NPs) with sizes below 10 nm are synthesized using hexadecylamine (HDA) as a stabilizing material, and HDA can prevent the irreversible aggregation of small-sized nanoparticles in solution-based reactions. The fabricated ultra-small APd NPs are investigated using UV–Vis, XRD, SEM, TEM, FTIR and TGA studies. In the presence of NaBH4 as a reducing agent, the APd NPs achieve high catalytic performance toward the degradation of dye pollutants such as 4-nitrophenol, methylene blue and methyl orange. Catalytic activity of alkylamine capped palladium nanoparticles for organic pollutant degradation.

Transparent conductive electrodes (TCEs) based on hybrid structures (silver nanowires) have been compressively reconnoitered in next-generation electronics such as flexible displays, artificial skins, smart windows, and sensors because of their admirable conductivity as well as flexibility, which make them favorable substitutes to replace ITO (indium tin oxide) as a transparent conductor. Nevertheless, silver-based TCEs grieve from poor stability because of the corrosion and oxidation of silver in electrolytes. To overcome these issues, a RGO (reduced graphene oxide) layer on silver was promoted to resolve the difficulties of corrosion and oxidation in the electrolyte. Moreover, we successfully designed and demonstrated low-voltage WO3-based electrochromic devices (ECDs) with fabricated hybrid TCEs. The hybrid electrodes with RGO/silver nanowires/metal grid/PET (RAM) electrode exhibited improvements in the switching stability and optoelectronic properties, such as the sheet resistance (0.714 ohm/sq) as we...

Noble-metal-free sustainable energy conservation has been attracting considerable attention for environmental protection and remediation. Herein, we present a low-temperature ( O, N–O, C–O–W, and C–O–W–N, which can alter the oxidation state of tungsten and boost-up the photocatalytic properties of O-g-C3N4/WO3. The optimized photocatalyst (O-g-CNW-4) produces higher H2 evaluation (15,142 μmol/g), which is 4.7 times higher than that produced by mechanical mixing samples. The prepared samples have highly porous structures with pore diameters of 20–30 nm. The C O, N–O, C–O–W, and C–O–W–N linkage vibrations of the prepared samples are analyzed, and their chemical confirmations and elemental oxidation states are verified. The oxygen-doped g-C3N4/WO3 porous structures exhibit large surface-areas with a huge quantity of active surface sites, band-structure modulation, and effective visible-light-harvesting of the photoinduced charge carriers, which is useful for enhancing photocatalytic H2 production.

Over the past few years, the photogenic fabrication of metal oxide nanoparticles has attracted considerable attention, owing to the simple, eco-friendly, and non-toxic procedure. Herein, we fabricated NiO nanoparticles and altered their optical properties by doping with a rare earth element (lanthanum) using Sesbania grandiflora broth for antibacterial applications. The doping of lanthanum with NiO was systematically studied. The optical properties of the prepared nanomaterials were investigated through UV-Vis diffuse reflectance spectra (UV-DRS) analysis, and their structures were studied using X-ray diffraction analysis. The morphological features of the prepared nanomaterials were examined by scanning electron microscopy and transmission electron microscopy, their elemental structure was analyzed by energy-dispersive X-ray spectral analysis, and their oxidation states were analyzed by X-ray photoelectron spectroscopy. Furthermore, the antibacterial action of NiO and La-doped NiO nanoparticles was studied by the zone of inhibition method for Gram-negative and Gram-positive bacterial strains such as Escherichia coli and Bacillus sublitis. It was evident from the obtained results that the optimized compound NiOLa-04 performed better than the other prepared compounds. To the best of our knowledge, this is the first report on the phytosynthetic fabrication of rare-earth ion Lanthanum (La3+)-doped Nickel Oxide (NiO) nanoparticles and their anti-microbial studies.

TiO2 nanoparticles anchored on the reduced graphene oxide (rGO) nanocomposites were prepared by hydrothermal method and characterized by the X- ray diffraction (XRD) and transmission electron microscopy (TEM). An effective electrochemical sensing platform for the detection of Rifampicin based upon TiO2 nanoparticles anchored graphene oxide sheets modified glassy carbon electrode (TiO2/rGO/GCE) is reported. Moreover, the TiO2/rGO modified glassy carbon electrode showed an excellent selectivity towards the detection of an anti-tuberculosis drug (Rifampicin). The TiO2/rGO/GCE electrochemical sensing platform is found to exhibit linear range from 0.01 – 0.1 nM with a low limit of detection 0.03 μM. The fabricated TiO2/rGO/GCE sensor is explored high sensitivity, high stable and good reproducible towards the sensing of RIF and has the potential to be utilized as a clinical assay and pharmaceuticals.

Metallic copper is a dependable co-catalyst for improving photoactivity of TiO2 photocatalysis. Cu@TiO2 core shell nanowires (NWs) were prepared by wet chemical synthesis and characterized. The microscopy images clearly show core shell morphology in nano regime. X-ray diffraction studies reveal the metallic copper and anatase TiO2 crystallinity. The optical absorption spectra exhibit ultraviolet and visible light harvesting properties. X-ray photoelectron spectroscopy confirms the presence of oxidation states of metallic copper and titanium. The photocatalytic efficiency was investigated by degrading the methyl orange (MO) and 3 wt% Cu@TiO2 core shell NWs shows highest degradation rate (k=0.02905 min−1) with superior photocatalytic activity. This material could be surely meet the necessities to harvest solar energy for many energy-related applications.

Copper nanowire (Cu NW)-based flexible transparent electronics represent an enormous breakthrough for the development of efficient, scalable and facile processing techniques. From the standpoint of commercialization, a cost-effective and eco-friendly procedure for welding nanowires is imperative to fabricate Cu NW network-based transparent electrodes. In this study, a photonic welding method using a white flash light (WFL) technique was developed in-house for welding Cu NWs in order to produce highly conductive and transparent electrodes under ambient conditions. Flexible Cu NW films with sheet resistances of 128 Ω □−1 and transmittances of >95% at 560 nm on PET substrates were obtained by using light intensity of 1.0 J cm−2 with single pulse and an irradiation time of 5 ms. The WFL technique facilitates localized surface heating and subsequent welding at the junction of the Cu NWs with excellent stability, low sheet resistance and no damage to the polymer substrates. It is expected that the WFL technique will be widely applied to flexible printed and optoelectronic devices such as touch panel displays and solar cells.

Nanobiotechnology is emerging as a rapid growing field with its applications in nanoscience and technology for the purpose of built-up new materials at the nanoregime. Nanoparticles produced by plant extracts are more stable, and the rate of synthesis is faster than that in the case of other organisms. In this paper we report the biosynthesis of zinc oxide nanoparticles (ZnO NPs). Structural, morphological, particle size, and optical properties of the synthesized nanoparticles have been characterized by using UV–Vis spectroscopy, Fourier transform infrared spectroscopy, field emission scanning electron microscope, energy-dispersive X-ray spectroscopy, atomic-force microscopy, zeta potential, X-ray diffraction, and photoluminescence intensity. The UV–Vis spectrum showed an absorption peak at 380 nm that reflects surface plasmon resonance. The optical measurements were attributed to the band gap 3.19 eV at pH 12. The zeta potential value of −36.4 eV revealed the surface charge of green synthesized ZnO NPs. The antioxidant activity was estimated by both 1,1-diphenyl-2-picrylhydrazyl and reducing power assay. Green synthesized ZnO NPs showed maximum inhibition (65.23 %) and absorbance (0.6 a.u). This approach offers environmentally beneficial alternative by eliminating hazardous chemicals and promotes pollution prevention by the production of nanoparticles in their natural environment.

Bio-based green nanotechnology aims to characterize compounds from natural sources and establish efficient routes for the preparation of nontoxic materials that have applicability in biodegradable and biocompatible devices. The present study has investigated the use of Plectranthus amboinicus leaf extracts as reducing and capping materials for the green fabrication of silver, gold, and silver-gold (Ag, Au, and Ag/Au) metal and bimetallic nanoparticles. The catalytic behavior of these phyto-inspired nanoparticles was then assessed in terms of the reduction of 4-nitrophenol. Transmission electron microscopy was used to investigate the shape, morphology, distribution, and diameter of the phytomolecules capped with Ag, Au, and Ag/Au metal nanoparticles. The nature of the crystallinity of the nanoparticles was studied by small area electron diffraction (SAED) and x-ray diffraction analysis (XRD), and Fourier transform infrared (FTIR) spectroscopy was used to study the reduction and stabilizing involvement of the phyto-organic moieties in aqueous medium. The phyto-inspired Ag and Ag/Au nanoparticles demonstrated good antibacterial properties toward Gram-negative Escherichia coli and Pseudomonas spp. and Gram-positive Bacillus spp. and Staphylococcus spp. microorganisms using the well diffusion method. Notably, the Ag nanoparticles were shown to possess effective antibacterial properties.

Facile approach to synthesize the metal oxide nanoparticles is getting an increased attention in various biomedical applications such as, to treat antibiotic resistant diseases. Magnesium oxide nanoparticles (MgO·NPs) were synthesized by using Clitoria ternatea as the stabilizer in a green synthesis approach. The preliminary screening of MgO·NPs in the presence of C. ternatea extract was observed by UV–visible spectrophotometer. X-ray diffraction (XRD) pattern have proved the crystalline nature of the MgO·NPs; Photoluminescence (PL) measurement studies are used to identify the quality and defects in the crystal structure. FE-SEM with EDS has showed the size of 50–400 nm with specific binding energies. FT-IR has revealed the functional groups present in the plant extract and the peak at 521 cm−1 indicated the characteristic absorption bands of MgO·NPs. The DPPH activity and reducing power assay of biologically synthesized MgO·NPs could reach 65 % at a concentration of 150 µg/ml, respectively. From the results it was concluded that the biologically synthesized MgO·NPs exhibit good antioxidant activity.