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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., (Copyright © 2014 Elsevier B.V. All rights reserved.)

In this study, we developed an innovative, flexible, organic-inorganic hybrid composite nanogenerator, which was used to drive a self-powered microwire-based pH sensor. The hybrid composite nanogenerator was fabricated using ZnO nanowire and piezoelectric polymer poly(vinylidene fluoride), through a simple, inexpensive solution-casting technique. The fabricated hybrid composite nanogenerator delivered a maximum open-circuit voltage of 6.9 V and a short-circuit current of 0.96 μA, with an output power of 6.624 μW under uniaxial compression. This high-performance, electric poling free composite nanogenerator opens up the possibility of industrial-scale fabrication. The hybrid nanogenerator demonstrated its ability to drive five green LEDs simultaneously, without using an energy-storage device. Additionally, we constructed a self-powered pH sensor, using a ZnO microwire powered with our hybrid nanogenerator. The output voltage varied according to changes in the pH level. This study demonstrates the feasibility of using a hybrid nanogenerator as a self-powered device that can be extended for use as a biosensor for environmental monitoring and/or as a smart, wearable, vibration sensor in future applications.

Transition metal oxide-based magnetic nanocomposites attract great attention due to their unique properties and applications in the field of energy storage. Herein, we present a facile microwave procedure for the synthesis of CuFe2O4 (CF) and CuFe2O4 incorporated with reduced graphene oxide CuFe2O4/rGO (CG) as potential electrode materials for hybrid supercapacitor. The structure and morphology of CF and CG nanoparticles are examined. The electrochemical performance is studied in 6 M aqueous KOH electrolyte using cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), and electrochemical impedance spectroscopy (EIS) techniques. The attractive CG nanocomposite exhibits high specific capacity of 800 C/g at a current density of 2 A/g and better cycling stability when compared to pure CF, due to the formation of nanostructure composed of ferrite nanoparticles homogeneously incorporated onto rGO sheets. Furthermore, the practicability of CG electrode is investigated by the fabrication of CG and activated carbon. The hybrid supercapacitor device shows excellent electrochemical performance with specific energy of 18.3 Wh/kg and a specific power of 455 W/kg. It is noteworthy that the cyclic stability is excellent with a capacity retention of ~98% after 3000 cycles manifesting the superiority of CG electrode. The proposed device demonstrates the potential to fabricate other metal oxides with activated carbon via a facile synthesis method for promoting application in energy storage materials and promoting new opportunities of binary nanocomposite. [ABSTRACT FROM AUTHOR]

The manuscript presents structural, optical and magnetic properties of CuFeO nanoparticles obtained employing a simple co-precipitation method in aqueous solution. Influence of ferric chloride concentration on the structural, optical and magnetic properties of CuFeO nanoparticles was investigated. XRD results clearly revealed the spinel tetragonal copper ferrite structures. The observed characteristic Raman E, F and A phonon mode of vibrations revealed the tetragonal copper ferrite structures. The observed PL results explored inverse spinel copper ferrite emission peaks in the range of visible region. IR result revealed the metal oxygen intrinsic vibrations of octahedral and tetrahedral sites in the spinel copper ferrite structure. SEM analysis clearly revealed the spherical shape morphology particles sizes are in the nano scale range. VSM studies clearly revealed that copper ferrite exhibit weak ferromagnetic behaviour. It was found that the ferric chloride concentration added to copper chloride precursor in the ratio of 1:1, 1:2 and 1:3 during the synthesis process played a significant role in structural and magnetic properties of the obtained product. [ABSTRACT FROM AUTHOR]

CuMn 2 O 4 nanoparticles were successfully synthesized by adopting solvothermal method with optimum hydrothermal processing temperature maintained at 160 °C for 12 h. The synthesized CuMn 2 O 4 nanoparticles structure, morphology, optical and electrochemical properties were analyzed with respect to varying the hydrothermal temperature. The product dominant XRD peak observed at 35.8° matches well with corresponding planes of standard data. The IR vibrational modes of Mn-O and Cu-O band were authenticated by the peak appearance at 526 and 630 cm −1 . The rice-like morphology formation of CuMn 2 O 4 nanoparticles prepared at 160 °C hydrothermal processing temperature revealed the superior behavior of electrochemical properties. The electrochemical studies carried out to estimate the specific capacitance of CuMn 2 O 4 nanoparticles (MX3) at low scan rate 10 mV/s showed an excellent specific capacitance value of 520.4 F/g. The GCD studies of synthesized rice-like morphology CuMn 2 O 4 nanoparticles (MX3) revealed superior specific capacitance of 577.9 F g −1 at 0.5 A g −1 and retain its 98% capacitance as 571.6 F g −1 at 1 A g −1 current density. [ABSTRACT FROM AUTHOR]

The monodispersed CuFe 2 O 4 nanoparticles were synthesized and optimized by employing solvothermal method and were studied by employing X-ray diffraction (XRD) method. The obtained products have tetragonal crystalline cubic-spinel type structure belonging to I 4 1 / a m d space group. The Raman and infrared studies analyzed the different vibration and starching modes of metal-oxide and the pure phase of the obtained CuFe 2 O 4 nanoparticles. The morphology nature of monodispersive CuFe 2 O 4 nanoparticles can be easily identified from field-emission scanning electron microscopy images, and the role of different molarities of KOH at 1, 5, and 10 M (BS1, BS2, BS3) can be clearly observed. The X-ray Photon spectroscopy (XPS) studies the oxidation states of the Cu-2p, Fe-2p and O-1s in CuFe 2 O 4 nanoparticles, which validates the XRD data and supports the crystalline formation. The specific capacitance of BS1 is 189.2 F/g at current density 0.5 A/g. As the current density increases, the diffusing rate of electrolyte ions into the electrodes will reduce, which is reflected in the specific capacitance of CuFe 2 O 4 nanoparticles. The cyclic stability of CuFe 2 O 4 nanoparticles (BS1) exhibits 84% retention after 1000 cycles of galvanostatic charging and discharging studies and the pattern of curve remains the same, which indicates very good coulomb efficiency after long cycles. • The specific capacitance of CuFe 2 O 4 is 189.2 F/g at current density 0.5 A/g. • CuFe 2 O 4 exhibits 84% retention after 1000 cycle's. • It exhibits very good coulomb efficiency after long cycles. [ABSTRACT FROM AUTHOR]

At present scenario, the design of newer energy storage devices primarily focuses on superior capacity, rate performance, cost-effectiveness and stability. Among the other available Bi-Transition Metal oxides (BTMO's), NiFe 2 O 4 is a favorable material for electrochemical supercapacitor (SC) applications due to the presence of two metal moieties. The strategy of combining carbon-based material with the metal ferrite improves the electrochemical behavior. Herein, we fabricated reduced graphene oxide (rGO) decorated with NiFe 2 O 4 nanoparticles using a commercially available microwave device. The as-prepared NiFe 2 O 4 /rGO (NG) nanocomposite exhibits a high surface area with increased porous nanoparticles that allow fast ion- diffusion which favors the electrochemical activity. Further, we have explored the use of bare and NiFe 2 O 4 /rGO samples for SC electrode application. The NG nanocomposite electrode material exhibits better electrochemical characteristics including a high specific capacity of 1320 Cg−1 at a current density of 1 Ag−1 and long cycle stability with 94% capacitance retention after 5000 cycles when compared to bare NF in alkaline (6 M KOH) electrolyte. In addition, we have assembled NG based full cell SC device using NG and activated carbon (AC) as electrodes. The fabricated SC device shows the high specific capacity and remarkable cyclic stability. It also exhibited an energy density of 75 Whkg−1 at a power density of 2343 Wkg−1 respectively. Hence, the proposed NG electrode material promotes new opportunities for utilizing this composite material as a promising electrode material for future energy storage devices. [Display omitted] • Nickel ferrite/rGO binary nanocomposite and Nickel ferrite nanoparticles prepared using microwave method is proposed. • NG nanocomposite shows high specific capacity of 1320 Cg−1 when compared to that of bare NF. • NG nanocomposite exhibits 94% capacitance retention after 5000 cycles at 4 Ag−1. • The fabricated supercapacitive device l exhibits energy density of 75 Whkg−1 at a power density of 2343 Wkg−1. [ABSTRACT FROM AUTHOR]

[Display omitted] • Antimony revealed rhombohedral crystal structure formation with D 3 d 5 (R 3 ¯ m) space group situated on symmetry C 3v sites. • In-plane longitudinal vibration (110.67 cm−1; E g) and out of plane vibration (A 1g ; 147 cm−1) revealed pure antimony. • The solution resistance value of Sb-NMP is 1.67 Ω and good conductive in nature. • Pure Sb (1.96 Ω) and Sb-Ball (1.93 Ω) exhibited low solution resistance value. • Sb-NMP showed exceptional HER performance with high stability of 80% retention. Modern research focuses exclusively on the search for relatively inexpensive, highly efficient electrocatalytic materials for the electrocatalytic hydrogen production water splitting reactions. Antimony is a chemical element having four allotropes with three oxidation states. Antimony is a semi-metal with elemental antimony. Recently, elemental antimony (Sb) with an extensive light absorption was recognized as good electrocatalytic for hydrogen evolution reactions. This study focuses on preparation and characterization of antimony nanoparticles for hydrogen evolution activities as explored. We report the structural, optical, vibrational, electrochemical properties of the pristine antimony nanoparticles for efficient catalytic material for electrochemical water splitting applications. The prepared antimony nanoparticles revealed the rhombohedral crystal structure formation with D 3 d 5 (R 3 ¯ m) space group situated on symmetry C 3v sites. In Raman studies, the peak appeared at 110.67 cm−1 corresponds to in-plane longitudinal vibration (E g) and at 147 cm−1 for out of plane vibration (A 1g) for pure antimony. The synergic effect of NMP and ultrasonication yields highly homogeneous antimony nanoparticles as evidenced from morphological analysis. From electrochemical impedance analysis, the solution resistance value of Sb-NMP is 1.67 Ω, which was small in comparison to the pure Sb (1.96 Ω) and Sb-Ball (1.93 Ω) and exhibited the good conductive nature of Sb-NMP nanomaterials. From electrochemical HER analysis, we found that the Sb-NMP showed the low 246 mV@10 mA/cm2 overpotential with low 186 mV/dec Tafel slope value. Furthermore, the chronoamperometry study exposed that the electrocatalyst Sb-NMP delivered an exceptional HER performance with high stability of 80% retention for continuous three hours measurements. Therefore, this study may perhaps facilitate the growth of antimony nanoparticles which can be used as an HER catalysts for improving the electrocatalytic HER activity. [ABSTRACT FROM AUTHOR]

• Nanocube MnSn(OH) 6 achieved 525F/g specific capacitance at 5 mV/s. • Yielded an outstanding LSV result of 281 mA/g for 10 mV/s. • Superior stability over 5 h of electrochemical OER activity. High performance MnSn(OH) 6 electrodes employing solvothermal processing route for energy conversion was explored. Single phase tetragonal MnSn(OH) 6 nanocubes were validated from sharp diffraction peak of crystal plane (2 0 0). Interaction with photons and nanocubes emissive character was deliberated. The characteristic Mn-O, Sn-O and OH vibrations of MnSn(OH) 6 nanocubes were evaluated. Uniform nanocube formation and its dispersive nature were examined. Fabrication of scalable high performance MnSn(OH) 6 electrodes was achieved by standard coating method and systematically analyzed to evaluate its electrocatalytic performance for energy applications. 525F/g specific capacitance at 5 mV/s achieved in favor of uniform nanocube morphology of MnSn(OH) 6 electrode. Obtained product yielded an outstanding linear sweep voltammetry (LSV) result of 281 mA/g for 10 mV/s whose electrical conductivity, electron mobility and charge transfer kinetics were investigated by electrochemical impedance spectra (EIS) and the superior stability over 5 h of electrochemical oxygen evolution reaction (OER) activity also proposed. High performance MnSn(OH) 6 nanocube synthesis and fabrication was achieved for electrochemical energy conversion application. [ABSTRACT FROM AUTHOR]

A SeO 2 nanostructure was prepared employing stabilized solvothermal method for water oxidation process in three electrodes cell set-up. Reducing agent influence on material morphology and its domination on electrochemical properties were investigated. Tetragonal structure of SeO 2 was confirmed from the crystal plane of (211) through X-ray diffraction (XRD) study. Reducing agent concentration was highly dominated the particle size and shape which was explored by field emission scanning electron micrograph (FESEM) images. The superior electrochemical specific capacitance of 572 F/g at 10 mV/s was afforded by SeO 2 nanoparticles synthesized via 15 M NaBH 4 by cyclic voltammogram (CV) study. The highest water oxidation performance of 292 mA/g at 10 mV/s was also demonstrated by the same electrode from linear sweep voltammogram (LSV), with better charge transfer and excellent stability. The exceptional performance of the SeO 2 electrocatalyst prepared by using highest NaBH 4 concentration evidenced its great role for potential applications. Image 1 • Superior electrochemical specific capacitance of 572 F/g at 10 mV/s was afforded by SeO 2. • Highest water oxidation performance of 292 mA/g at 10 mV/s was demonstrated. • Better charge transfer and excellent stability was afforded by SeO 2. [ABSTRACT FROM AUTHOR]

• Unique layered structural property enhanced electrochemical performance. • Increased specific capacitance of 1100 Fg−1 at 0.5 A/g at 0.5 V. • Better rate capability and stability achieved within studied range. • Product explored enhanced stability and retains 98.1% after 2000 cycles. Material storage property enrichment with good electrochemical performance is a foremost challenge. Cobalt hydroxide and reduced graphene oxide (rGO) composite synthesized via chemical precipitation method showed improved specific capacitance and cycle stability. The unique rGO layered structure in composite enhanced overall electrochemical performance. Raman spectra revealed disordered rGO structure and A 1g mode of Co(OH) 2 in composite. rGO/Co(OH) 2 electrode showed increased specific capacitance of 1100 Fg−1 at 0.5 Ag−1 with better rate capability and good stability (98.1%) after 2000 cycles. These results proved that rGO/Co(OH) 2 is a perfect electrode for electrochemical energy storage applications. [ABSTRACT FROM AUTHOR]

• Novel cost effective and greener microwave synthesis of Cu 2 O/MoS 2 /rGO is proposed. • Sheets of MoS 2 /rGO composite were wrapped over Cu 2 O nanoparticles for better performance. • Cu 2 MG exhibits enhanced supercapacitive behaviour with excellent cyclic stability. Novel Cu 2 O/MoS 2 /rGO nanostructure has been synthesized using simple and cost-effective microwave method. SEM and TEM observations confirm spherically-shaped Cu 2 O nanoparticles coated simultaneously with MoS 2 and rGO thin layers. The nanocomposite electrode exhibits high specific capacitance of 388F/g with excellent cyclic stability of 95.6% retained over 3000 charge–discharge cycles. The as-fabricated nanomaterial is a potential candidate for supercapacitor applications. [ABSTRACT FROM AUTHOR]