Microwave engineered NiZrO3@GNP as efficient electrode material for energy storage applications.

Supercapacitors (SCs) have emerged as attractive energy storage devices due to their rapid charge/discharge rates, long cycle life, and high-power density. However, the development of innovative electrode materials to achieve high-performance remains crucial to meet future requirements in supercapacitor technology. In this work, we have explored the potential of a microwave-engineered NiZrO3@GNP composite as a promising electrode material for SCs. A microwave assisted hydrothermal approach was adopted for the fabrication of the NiZrO3@GNP nanocomposite. Structural and morphological investigations showed its structural richness and its chemical compositions. When applied as a SC electrode, this innovative combination exhibits battery-like behaviour with higher specific capacity (577.63 C g-1) with good cyclic stability, and good performance. We have assembled an asymmetric-type two-electrode SC device and analysed its electrochemical features. This NiZrO3@GNP device exhibits the specific capacity of 47 C g-1 with capacitance retention of 70% after 2000 charge-discharge cycles. Further research on optimizing the synthesis process and exploring different device configurations could pave the way for even higher-performance supercapacitors in the future.

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

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

Cleaner production of tamarind fruit shell into bio-mass derived porous 3D-activated carbon nanosheets by CVD technique for supercapacitor applications.

This paper reported the successful preparation and characterization of bio-activated carbon nanosheets (ACNSs) synthesized from tamarind (tamarind indicia) fruits shells (TFSs) by employing Chemical Vapor Deposition (CVD) tubular furnace. The preparation of pure ACNSs and also potassium hydroxide (KOH) activated carbon nanosheets (K-ACNSs) were made through a pyrolysis process with Argon (Ar) gas as an inert gas at 800 °C for 2h 30min, followed by further purifications of K-ACNSs. The scanning electron microscope (SEM) images of ACNSs and K-ACNSs explored with and without pores respectively. The SEM micrographs also explored 3D-porous microstructure sheets with thickness around 18-65 nm. Raman spectroscopy explored crystallinity, SP2 order and graphitization at 1577-1589 cm-1. The major functional groups were also observed. The photoluminescence (PL) was analyzed for K-ACNSs materials and revealed carbon emission broad peak value at 521.3 nm. As prepared ACNSs and K-ACNSs active materials was applied for three-electrode materials of energy storage supercapacitor analysis of cyclic voltammeter for -0.4 - 0.15 V at scan rates of 10-100 mV/s. The electrochemical impedance spectroscopy (EIS) was performed with low Rct values of K-ACNSs as 0.65Ω when compared to pure ACNSs as 5.03Ω. Mainly, the galvanostatic charge-discharge test carried out in ACNSs and KCNSs materials was corresponded to 77 and 245.03 F/g respectively, with respect to 1 A/g current density. Finally, we promise that this reported novel tamarind bio-waste into conductive porous carbon nanosheets could develop future energy storage applications of biomass-derived carbons.

Asymmetric polyhedron structured NiSe2@MoSe2 device for use as a supercapacitor.

The polyhedron-structured NiSe2@MoSe2 (NMS) were magnificently produced through hydrothermal method, which makes the active electrode very effective in accessing the redox active sites in the charge/discharge process in supercapacitor applications. Systematic studies of the structural and morphological features of the unique polyhedron NMS were performed. Laser Raman spectra reported the vibrational and rotational modes of NMS. NMS exhibited a maximum 1000 F g-1 (138.8 mA h g-1) specific capacitance at 1 A g-1 and attained a capacity retention of 77.67% for 5000 stable cycles at 10 A g-1 using 1 M KOH as an electrolyte. The well assembled asymmetric supercapacitor NMS hydrolyzed for 18 h//AC demonstrated an outstanding electrochemical performance with an improved 305 F g-1 specific capacitance attained at 1 A g-1 with a good cycle life of 87.35% and a capacity retention of over 5000 cycles. Herein, the combined contribution of both the Ni and Mo ions offers a richer redox chemistry, which is beneficial to a higher electrochemical activity. The experimental results indicate that the NMS electrode could be used as a high-performance electrode.

Nickel-cobalt hydroxide: a positive electrode for supercapacitor applications.

So far, numerous metal oxides and metal hydroxides have been reported as an electrode material, a critical component in supercapacitors that determines the operation window of the capacitor. Among them, nickel and cobalt-based materials are studied extensively due to their high capacitance nature. However, the pure phase of hydroxides does not show a significant effect on cycle life. The observed XRD results revealed the phase structures of the obtained Ni(OH)2 and Co-Ni(OH)2 hydroxides. The congruency of the peak positions of Ni(OH)2 and Co-Ni(OH)2 is attributed to the homogeneity of the physical and chemical properties of the as-prepared products. The obtained results from XPS analysis indicated the presence of Co and the chemical states of the as-prepared composite active electrode materials. The SEM analysis revealed that the sample had the configuration of agglomerated particle nature. Moreover, the morphology and structure of the hydroxide materials impacted their charge storage properties. Thus, in this study, Ni(OH)2 and Co-Ni(OH)2 composite materials were produced via a hydrothermal method to obtain controllable morphology. The electrochemical properties were studied. It was observed that both the samples experienced a pseudocapacitive behavior, which was confirmed from the CV curves. For the electrode materials Ni(OH)2 and Co-Ni(OH)2, the specific capacitance (C s) of about 1038 F g-1 and 1366 F g-1, respectively, were observed at the current density of 1.5 A g-1. The Ni-Co(OH)2 composite showed high capacitance when compared with Ni(OH)2. The cycle index was determined for the electrode materials and it indicated excellent stability. The stability of the cell was investigated up to 2000 cycles, and the cell showed excellent retention of 96.26%.

MnFe2O4 Nanoparticles as an Efficient Electrode for Energy Storage Applications.

In this study, solvothermal method was used for the synthesis of MnFe2O4 nanoparticles at different processing period of 7, 14, and 21 h. X-ray diffraction (XRD) pattern study confirms that MnFe2O4 nanoparticles correspond to the face-centered cubic spinel structure and belong to the Fd3m [227] space group. From Raman spectra analysis, two major peaks were observed at 476 and 616 cm-1, which correspond to the vibration modes of MnFe2O4 nanoparticles; especially, the broad peak at 620 cm-1 (A1g) corresponds to the symmetric stretching vibration of oxygen atoms at tetrahedral site. Infrared spectra (FTIR) analysis at 490 and 572 cm-1 can be attributed to the stretching vibration of tetrahedral groups of FeO4, and the vibration of octahedral groups of FeO6 belongs to the intrinsic vibrations of manganese ferrites. The uniformly distributed MnFe2O4 nanospheres (RT2) can be affirmed by field emission scanning electron microscopy images and confirmed by the high-resolution transmission electron microscopic studies. The electrochemical properties of synthesized MnFe2O4 nanoparticles investigated by cyclic voltammetry, impedance spectroscopy and galvanstatic charging and discharging (GCD) studies clearly predict the reversible faradaic reactions of MnFe2O4 nanospheres. Further, the MnFe2O4 nanospheres (RT2) exhibit high specific capacitance of 697 F g-1 at 0.5 A g-1 current density in galvanostatic charging and discharging profile and after 1000 cycles exhibits 79% retain ability of initial specific capacitance and hence can be considered as the efficient electrode for supercapacitor applications.

Synthesis of X3(PO4)2 [X = Ni, Cu, Mn] Nanomaterials as an Efficient Electrode for Energy Storage Applications.

In this study, a general and effective phosphorization strategy is demonstrated to enhance the super capacitor performance of Ni, Cu, and Mn transition metals. The composites such as Ni3(PO4)2, Cu3(PO4)2 and Mn3(PO4)2 were achieved by employing hydrothermal method mixing with ethylene glycol. These composite nanostructures were characterized by standard sophisticated techniques such as XRD, RAMAN, FTIR, UV, PL and SEM studies. X-ray diffraction (XRD) studies revealed the monoclinic crystallographic structure of the materials. The optical and vibrational properties of the product are characterized by photoluminescence and FTIR studies. These prepared materials have shown desired electrochemical stability. The above characterization indicates the functional groups and materials nature. The electrochemical properties of synthesized phosphate materials are analyzed by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and galvanostatic charging and discharging studies (GCD). The Cu3(PO4)2 electrode showed a remarkable specific capacitance of 232.025 F g-1 at a scan rate of 20 mV/s, which is expected to have a promising electrode for super capacitor applications. The GCD study of synthesized Cu3(PO4)2 nanostructure has also been tested for 1000 cycles at 10 A/g current density to evaluate the cyclic stability of the electrode and retains 94% of initial specific capacitance.

Low Surface Energy and pH Effect on SnO2 Nanoparticles Formation for Supercapacitor Applications.

The SnO2 nanoparticles formation by hydrothermal method at different experimental conditions such as temperature, pH, reaction time, and capping agent (cetyltrimethylammonium bromide), was studied. X-ray diffraction results confirmed regular rutile crystal structure of SnO2. The characteristic Raman peak observed at 635 cm-1 corresponded to A1g modes of Sn-O vibrations. The study of optical property using photoluminescence confirmed the emissive spectra of SnO2. The infrared peak observed at 618 cm-1 corresponded to Eu modes of Sn-O vibrations of TO phonon because of E⊥ to c-axis. Scanning electron microscope images clearly revealed the formation of complete SnO2 nanoparticles. The unique SnO2 nanoparticles stacked together to form microspheres at pH-5 showed high specific capacitance of 274.8 F/g at a current density of 0.5 A/g. The observed results confirmed the feasibility of SnO2 nanoparticles being used as appropriate positive electrode candidate for supercapacitor applications.

Structural, Optical and Magnetic Properties of NiO Nanopowders.

Nickel oxide (NiO) nanopowders were synthesized without using surfactant by chemical reduction technique. NaBH4 influence on structural, optical and magnetic properties of NiO product was investigated. XRD results revealed the formation of dominant single phase, cubic face centered nickel oxide. Raman peaks depicts the characteristic first-order transverse optical (TO) phonon, two phonon excitation (TO + LO), excitation (2LO) Raman mode vibrations of face centered cubic NiO. PL studies revealed the presence of strong emission band which is in good agreement with the intrinsic NiO product. FTIR studies explored metal oxygen vibrations of the obtained product. TEM results revealed the nanoscale product with spherical shape structures. VSM studies explored weak ferromagnetic behavior of the obtained product. High concentration of NaBH4 increases magnetization value and exhibits the typical weak ferromagnetic curve. Reducing agent played a vital role in the structural, optical and magnetic properties of the obtained NiO product.

Hexamine Role on Pseudocapacitive Behaviour of Cobalt Oxide (Co3O4) Nanopowders.

Influence of hexamine surfactant concentration on crystallite size, structure, morphology, vibrational and optical properties of cobalt oxide nanopowders were explored. The cobalt oxide nanopowders were synthesized by employing a simple chemical reduction method using cobalt (II) nitrate hexahydrate (Co(NO3)2 ·6H2O) as precursor and sodium borohydride (NaBH4) as reducing agent along with hexamine as surfactant. XRD studies revealed the formation of face-centered cubic (Fd3m) crystalline structure of Co3O4 with an average crystallite size of 8-18 nm. The observed prominent characteristic Raman active modes of A1g, Eg, and F2g revealed the formation of Co3O4 nanopowders. The optical properties of Co3O4 nanopowders are examined by photoluminescence spectra. The obtained IR results confirmed the formation of Co3O4 nanopowders. The band observed 569 cm-1 is the characteristic of the Co3+ ions in the octahedral hole vibration and the 665 cm-1 band is attributable to the Co2+ ions in the tetrahedral hole vibration in the cubic lattice. The estimated specific capacitance of the obtained Co3O4 nanopowders was 291 F/g at 10 mV/s which could be a potential candidate for pseudo capacitive nature of the active materials.

Fine cutting edge shaped Bi2O3rods/reduced graphene oxide (RGO) composite for supercapacitor and visible-light photocatalytic applications.

Bi2O3 rods/RGO composite has been synthesized by a simple precipitation and calcination method. The crystallnity, structural, and morphological features were studied by X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), and high resolution transmission electron microscopy (HR-TEM) techniques. The supercapacitor behavior was studied using cyclic voltammetry, galvanostatic charge discharge and impedance analysis, respectively. The Bi2O3 rods/RGO nanocomposite exhibits a maximum specific capacitance of 1041Fg-1 at a current density of 2Ag-1. The photocatalytic activity of Bi2O3 rods/RGO composite was evaluated by photocatalytic degradation of methylene blue (MB) dye under visible-light irradiation. The enhancement of photocatalytic properties of Bi2O3 rods/RGO composite attributed to the synergistic effect between Bi2O3 rods and graphene sheets which effectively prevents recombination of the photogenerated electron-hole pairs in Bi2O3 rods. The present study provides a new approach in improving the performance of Bi2O3 rods/RGO composite in energy and environmental applications.

Rambutan peels promoted biomimetic synthesis of bioinspired zinc oxide nanochains for biomedical applications.

A naturally occurring rambutan peel waste was employed to synthesis bioinspired zinc oxide nanochains. Rambutan peels has the ability of ligating zinc ions as a natural ligation agent resulting in zinc oxide nanochains formation due to its extended polyphenolic system over incubation period. Successful formation of zinc oxide nanochains was confirmed employing transmission electron microscopy studies. About 60% and ∼40% cell viability was lost and 50% and 10% morphological change was observed in 7 and 4 days incubated ZnO treated cells compared with control. Moreover, 50% and 55% of cell death was observed at 24 and 48 h incubation with 7 days treated ZnO cells and hence alters and disturbs the growth of cancer cells and could be used for liver cancer cell treatment.

Awareness and knowledge of common oral diseases among primary care physicians.

OBJECTIVE: The objectives of this study were to examine the level of awareness of the common oral disease amongst the primary care physicians in Chennai, India and to study the proportion of the routine oral examination among them. METHOD: This study was a cross-sectional, self administered, questionnaire survey which was done among 70 primary care physicians of Chennai, India. The questionnaire assessed the proportion of the routine oral examination and the knowledge and the awareness about the common dental problems among the primary care physicians. RESULT: This study showed moderate awareness about the signs and symptoms of the common oral diseases. There appeared to be a low awareness about the treatment of limited mouth opening and the causes of white patches. 85.9% of the doctors said that they routinely examined the oral cavity; 4.2% said that they sometimes did so. 4.2% of the sample said that they did not perform a routine oral examination, whilst another 4.2% said that they examined the throat only. CONCLUSION: The information which was gleaned from this study can help in developing a focused module which is aimed at the practising primary care physicians, and to suggest appropriate additions to the curriculum of the medical graduates, so as to enable an early detection, an appropriate referral, and an ultimately improved oral and general health of our population.

Interconnected V2O5 nanoporous network for high-performance supercapacitors.

Vanadium pentoxide (V(2)O(5)) has attracted attention for supercapcitor applications because of its extensive multifunctional properties. In the present study, V(2)O(5) nanoporous network was synthesized via simple capping-agent-assisted precipitation technique and it is further annealed at different temperatures. The effect of annealing temperature on the morphology, electrochemical and structural properties, and stability upon oxidation-reduction cycling has been analyzed for supercapacitor application. We achieved highest specific capacitance of 316 F g(-1) for interconnected V(2)O(5) nanoporous network. This interconnected nanoporous network creates facile nanochannels for ion diffusion and facilitates the easy accessibility of ions. Moreover, after six hundred consecutive cycling processes the specific capacitance has changed only by 24%. A simple cost-effective preparation technique of V(2)O(5) nanoporous network with excellent capacitive behavior, energy density, and stability encourages its possible commercial exploitation for the development of high-performance supercapacitors.