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Bi0.617Y0.05Cu3Ti4O12(BYCTO) was successfully synthesized through an economically semi-wet route using metals nitrates, acetate, and TiO2 precursor and sintered at 1173 K for 8 h. The single phase of ceramic was authorized by XRD analysis. The crystallite size of BYCTO ceramic was calculated to be 62.3 nm through XRD measurement. The particle size obtained by TEM analysis was to be in the range of 55 ± 7 nm. The average grain size observed through the SEM technique was 0.783 μm. The route means square roughness, as well as average roughness, were determined to be 0.224 μm and 0.179 μm by atomic force microscope. The dielectric constant (ɛ′) of BYCTO was measured to be 1481 at 307 K and 100 Hz. The tangent loss (tan δ) was observed to be in the range of 0.13–0.29 at all selected temperatures (307–487 K) and 10 kHz which is lower than that of Bi2/3Cu3Ti4O12. The oxidation state of all metal present in the ceramic material was verified by XPS analysis.

Polycrystalline Bi36Fe2O57 (BFO) ceramic was prepared by an economical chemical route. The X-ray powder diffraction analysis shows the formation of single-phase BFO ceramic. Nanosized formation of BFO ceramic particles was characterized by XRD as well as TEM and had particle size 76 ± 10 nm range. The sillenite type Bi36Fe2O57 shows better photocatalytic activity for the methylene blue (MB) dye degradation under visible light exposure than the perovskite-based BiFeO3 due to the low band gap(1.8eV) of the former. The photocatalytic mechanism of MB degradation over Bi36Fe2O57 ceramic can be explained by the Langmuir-Hinshelwood model which reflects the adsorption-controlled photocatalytic process.

We report simultaneous crystal growth and deposition of upconverting Yb3+/Er3+ doped NaYF4 film (UCF) on conducting and non-conducting substrates by one-step hydrothermal method. The characteristics such as film topography, morphology, crystallographic phase and upconverting luminescence intensity were found to depend both on the chelating agent and nature of the substrate. The characteristics of the prepared films varied interestingly when either the chelating agent or the substrate was changed. The upconversion emission intensities were found to increase with decreasing film roughness. Further, current investigation demonstrated that the NaYF4 films deposited using EDTA or DTPA chelating agents on ITO substrate and EGTA chelating agent on PG substrate were more uniform and resulted in greater upconverted emission intensities. We envision plausible use of current technology in the development of affordable optical platforms for several optoelectronic applications.

Bi2Fe4O9 crystalline ceramic was successfully synthesized through a soft chemical route at lower sintering temperature for analysis of photocatalytic behavior with respect to adsorption of Congo Red (CR) in the presence of UV-VIS irradiation. The single-phase formation of Bi2Fe4O9 ceramic was confirmed by powder X-ray diffraction studies and particle size observed by TEM analysis was found to be 148 ± 5 nm which reveals the crystalline nature of the materials. Additionally, the photocatalytic activity of Bi2Fe4O9 ceramic was evaluated by the degradation of Congo Red in presence of visible light. The optical band gap (Eg) of the synthesized materials was found to be 1.8 eV. It exhibited greater photocatalytic activity than other synthesized materials like BiFeO3 as well as TiO2 due to a smaller band gap (1.8 eV). Furthermore, process variables such as pH.

In this study, pyrolysis of agricultural residues, such as rice straw (RS), wheat straw (WS), and sugarcane bagasse (SB), was performed in a fixed-bed reactor. The experiments were carried out at varying operating conditions, such as temperature, heating rate, biomass particle size and sweeping gas flow rate, such that the bio-oil yield could be maximized. Small particle size and high heating rate contributed to more bio-oil yield as compared to large particle size and low heating rate. Physicochemical properties of bio-oil samples, evaluated in a comparative manner with maximum focus devoted on analyzing the chemical constituents through GC–MS and FTIR analysis. Biochar was also examined through different physicochemical techniques (e.g., HHV, pH, SEM–EDX, FTIR, CHNS, ICP-AES) for understanding pyrolysis mechanism and its practical usability. Analysis of non-condensable gas through GC-TCD, revealed co-existence of H2, CO, CO2 and CH4 molecules, with greater percentage of H2 and CH4 at high temperature resulted enhancement in calorific value.

Bismuth ferrite nanostructure, BiFeO3, (BFO) belonging to perovskite family, was synthesised by a chemical route sintering temperature at 800°C for 6 h. The crystalline phase of the materials was i...

Ultra-small (1.6 nm), water-soluble, white light-emitting (WLE), highly stable (∼8 months) BSA templated metallic (Mg0) nanoclusters (fluorescent magnesium nanoclusters = FMNCs) is developed using the green and facile route. Synthesis was facilitated by the reduction of magnesium salt, where template bovine serum albumin is utilized as a reducing agent and ascorbic acid act as a capping agent to impart stability in water, thereby obtaining stabilized Mg0 nanoclusters In solution, stabilized Mg0 nanoclusters produce white light (450–620 nm with FWHM ∼120 nm) upon 366 nm light excitation. This white light emission was found to have a CIE coordinate of 0.30, 0.33 [pure white light CIE (0.33, 0.33)]. Taking advantage of WLE and ultrasmall size, FMNCs were used for in vitro fluorescence imaging of HaCaT cell lines, yielding blue (τ = 2.94 ns, with a relative of QY = 1.2 % w.r.t QS), green (τ = 3.07 ns; relative quantum yield of 4.6% w.r.t R6G) and red (τ = 0.3 ns) images. Further, incubation of FMNCs with HEK293 (Human embryonic kidney cell) and cancerous MDA-MB-231 (Breast cancer cell line) human cell lines yielded 100 % cell viability. Current work is envisioned to contribute significantly in the area of science, engineering, and nanomedicine.

A new organic complex (ANNBA) was synthesized using the solvent-free, solid-state reaction involving anthranilamide (AN)

The development of a sensitive α-NaYF4:Yb3+,Er3+ solid-phase upconverting platform (UCP) was realized using Moringa oleifera leaf extract for selective detection of the trivalent arsenic ion [As(III)] contamination in drinking water. The presence of polyphenols in the leaf extract were shown to induce luminescence resonance transfer (LRET), thereby diminishing the Er3+ emission (red and green band) when activated by 980 nm excitation. However, the addition of As(III) species interrupted the LRET process and restored the emissions proportionately. This feature allowed the platform to selectively detect arsenic pollution in water below the safe limit of 10 ppt. The uniqueness of UCP lies in monitoring the As(III) contamination in samples containing heavy ions (Cd2+ and Hg2+) also, without an apparent effect on the signal reproducibility. The UCP was also found to be insensitive to other interfering ions including Pb2+, H2PO4−, F−, Cl−, Ca2+, Mg2+, Sn2+, Cr6+, Fe2+ and Co2+, if present.

The development of a sensitive α-NaYF4:Yb3+,Er3+ solid-phase upconverting platform (UCP) was realized using Moringa oleifera leaf extract for selective detection of the trivalent arsenic ion [As(iii)] contamination in drinking water. The presence of polyphenols in the leaf extract were shown to induce luminescence resonance transfer (LRET), thereby diminishing the Er3+ emission (red and green band) when activated by 980 nm excitation. However, the addition of As(iii) species interrupted the LRET process and restored the emissions proportionately. This feature allowed the platform to selectively detect arsenic pollution in water below the safe limit of 10 ppt. The uniqueness of UCP lies in monitoring the As(iii) contamination in samples containing heavy ions (Cd2+ and Hg2+) also, without an apparent effect on the signal reproducibility. The UCP was also found to be insensitive to other interfering ions including Pb2+, H2PO4-, F-, Cl-, Ca2+, Mg2+, Sn2+, Cr6+, Fe2+ and Co2+, if present.

A low cost polyvinyl alcohol-glutaraldehyde cross-linked hydrogel beads were prepared and used for color removal from model industrial effluent containing Congo Red dye, using adsorption technique. The adsorption studies were performed using batch and fixed-bed reactor. Developed adsorbent, achieved adsorption capacity as high as ~34 mg of dye per gram of bead (condition: pH 6 and 45 °C). These beads were re-used for 7 times (many more runs possible) to remove the color from model dye effluent, without much loss in removal efficiency. Batch studies revealed a multi-layer adsorption governed by Harkins Jura model. Whereas the adsorption kinetics followed fractal like pseudo second order model, controlled by intraparticle diffusion phenomena. The fixed bed studies revealed steeper break through curves during adsorption operation when high dye influent rates and low bed height were used. This behaviour by the fixed bed reactor was best explained by the Thomas mathematical model. Studies further demonstrated that an external and internal mass diffusion become no more rate limiting during these experiments.

The development of a sensitive alpha-NaYF4:Yb3+, Er3+ solid-phase upconverting platform (UCP) has been realized using Moringa oleifera leaf extract for selective detection of arsenic (As III) contamination in drinking water. The presence of polyphenols in the leaves extract is shown to induce luminescence resonance transfer (LRET), diminishing thereby the Er3+ upconverting red and green emissions activated by 980 nm excitation. However, addition of As3+ species interrupts the LRET process and restores emission proportionately. This feature allows platform to selectively detect arsenic pollution in water below the safe limit of 10 ppt. The uniqueness of UCP lies in monitoring the As3+ contamination in samples containing heavy ions (Cd2+, Hg2+) as well, without apparent effect on the signal reproducibility. UCP is also found to be insensitive to other interfering ions like Pb2+, H2PO4-, F-, Cl-, Ca2+, Mg2+, Sn2+, Cr6+, Fe2+ and Co2+, if present.

Fluorescent atacamite nanoclusters (FANCs) have been developed and modified with silica for Drosophila salivary gland tissue imaging and photothermally induced cell death of osteosarcoma MG-63 cells. FANCs were synthesized with Moringa oleifera leaf extract without using any hazardous reducing and external capping agents. FANC was further used to evaluate light absorption, fluorescence emission, band gap, and magnetic properties as the first report on such nanoclusters. Upon excitation with a 350 nm light source, FANCs exhibited fluorescence at 460 nm, with a relative quantum yield of 0.3%. Besides, silica-encapsulated fluorescent atacamite nanoclusters (SEFANC) manifested remarkable improvement in emission, quantum yield (1.7%), shelf-life (15 d), biocompatibility, and photostability. Concomitantly, it has also increased the absorption in the near-infrared region and demonstrated high heat generation potential (42 °C → 50 °C). The above results suggest that FANC can be a potential candidate in the area of nanomedicine for a number of applications such as bioimaging, photothermal therapy, etc.

In this study, we have synthesized fluorescent carbon quantum dots (J-CQDs) from Jatropha fruit by using a one-pot hydrothermal approach, for the first time. The as-synthesized J–CQDs exhibited bright blue fluorescence emission with a high quantum yield of 13.7 %. Furthermore, the synthesized fluorescent J-CQDs have been used as a fluorometric sensor for the detection of pesticides. The sensing of pesticides is based on the irreversible catalytic inhibition of acetylcholinesterase (AChE) enzyme with a controlled fluorescence quenching process. The thiocholine was mainly triggered by the decomposition of DTNB to form yellow-colored TNBA. Further, TNBA gradually quenched the fluorescence emission spectra of added J-CQDs via dynamic quenching. The catalytic activity of AChE was inhibited in the presence of OPs, leading to the recovery of the fluorescence signal. Thus, a sensitive and selective nanoprobe was designed for the sensing of OPs (chlorpyrifos) along with a detection limit 2.7 ng/mL. Apart from this, the proposed sensing method has been successfully applied for pesticide detection in environmental and agricultural samples with acceptable recovery. Thus, the delivered result suggests that our probe is simple in design, having a short reaction time, and could be proficiently used in further analytical and environmental applications in the future.