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Due to environmental crisis and developed numerous portable electronic device and electric vehicles, it is necessary to find commercial alternative energy source to fulfil the future charge storage demand. In the present work, we have addressed the facile sol–gel root for the synthesis of Bismuth ferrite (BFO) along with modified carbon solution. The effect of carbon on structure, morphology and electrical properties on the BFO ceramic were investigated. XRD study reveals the prepared samples were found to be highly amorphous and rhombohedral structure. The morphology analysis demonstrates that the modified BFO nanoparticles size (∼20 nm) is smaller than pure BFO of size (∼30 nm) which helps to reduces the leakage current and improved electrical properties. Influence of carbon solutions on the BFO have been investigated for supercapacitor application. The modified BFO exhibited good electrochemical energy storage performance with a specific capacity of 678 Fg−1 at a scan rate of 5 mVsec−1 and excellent cyclic retention ∼90.5% even after 3000 cycles. In addition, the developed electrode materials are used to fabricate an asymmetric solid-state supercapacitor (ASC) device for demonstrating the practical applicability.

Understanding the concept of light–matter interaction in organic–inorganic nanostructures such as graphene and metal-halide perovskites has been explored to realize photonic and optoelectronic devi...

Lead-free Ba0.85Ca0.15Zr0.1Ti0.9O3 piezoelectric nanofiber was synthesized using the electrospinning technique. The surface of sintered BCZT nanofibers was modified by dopamine via the chemical coating method. Dopamine-modified BCZT nanofibers were used as fillers in polyvinylidenefluoride–hexafluoropropylene (PVDF-HFP) polymer matrix to cast flexible composite films by solution casting method. Nanofibers and composite films were analyzed by XRD and FE-SEM to investigate crystal structure and morphology, respectively. The broadband dielectric spectroscopy was carried out in composite films having 3.4–24.1 vol% BCZT nanofibers. The composite film having 24.1 vol% nanofibers showed a maximum dielectric constant (61 at 1 kHz) compared with other films. A flexible nanogenerator (NG) was fabricated using epoxy as a packing material. The developed NG tested in different tapping modes and exhibited maximum output voltage and power density around 10 V and 2.9 μW/cm3, respectively.

Phase pure BiFeO3 (BFO) and Bi0.98Ba0.02Fe1-xCrxO3 (x = 0.01, 0.02, 0.03, 0.04) nanoparticles were synthesized by a facile sol-gel route. X-ray diffraction data confirms rhombohedral R3c phase of BFO and Ba, Cr co-doped BFO nanoparticles with a slight distortion at higher dopant concentration. TEM images verified the higher crystallinity of the samples with a significant reduction in particle size (∼40 nm) with increasing Cr concentration. The band gap of pristine BFO nanoparticles was found to be 1.8 eV which increases remarkably to a maximum of 2.32 eV for Ba, Cr co-doped BFO nanoparticles. 57Fe Mossbauer spectroscopy confirmed that no mixed valance state of Fe was present in the Ba, Cr co-doped BFO nanoparticles. Hysteresis loops of all the samples revealed the weak ferromagnetic nature of the co-doped BFO nanoparticles. It was observed that the saturation magnetization increased by more than 3 times when Cr content was increased from 1% to 4%.

In present study, we have synthesized intrinsically conductive poly(1,6-heptadiynes) via cyclopolymerization technique, and further it is composited with the NiFe2O4 to fabricate pellet for electrical and electronic applications. The synthesized polymer I–V characteristics were obtained by two-probe measurement technique. The results suggest that the high current density of the synthesized polymer was in the range of 1.2 × 10–5–3.1 × 10–5 S/cm, which attributes to the potentially induced hoping charge-carrier mechanism within the conjugated poly(1,6-heptadiynes). NiFe2O4 and NiFe2O4/poly(1,6-heptadiynes) composite pellets were fabricated by utilizing hydraulic pelletizer. The sample’s electrical measurements were performed via broad-band dielectric impedance spectroscopy, wherein the composite permittivity was about ε = 45 (100 Hz to 10 kHz), which attributes to the NiFe2O4 and poly(1,6-heptadiynes) phases; further, this describes the capacitance, which improved from 0.3 to 0.1 pf at 1 kHz. Also, these results suggest the reduced equivalent series resistance (72.1–1 MHz), which attributes to the incorporated intrinsically conducting poly(1,6-heptadiynes). Thus, the reduced dissipation factor (DF = 0.0032) was observed from impedance characteristics of a nanocomposite. Moreover, the improved Q-factor was observed, which was about 8.1–310 at 1 kHz. The resistance and capacitance time constant was also computed to be about 0.29 μs at 1 kHz for NiFe2O4/poly(1,6-heptadiynes) nanocomposite. Furthermore, the nanocomposite-enabled capacitor gravimetric energy density and power densities were calculated to be about 0.00575 mJ/g and 9.91 W/g, respectively. Additionally, thermal threatening, that is, heat generated within the capacitor, Ploss is also estimated for the nanocomposite capacitor, which improved from 0.0006 to 8.9 × 10–6, and these results suggest improved nanocomposite thermal stability. Further, the delineated quantities were compared to the commercially available configurations of tantalum hybrid capacitors and Al and Ta electrolytic capacitors, including carbon electrochemical capacitors, which suggest that the reported nanocomposites could be a suitable candidate for electrical and electronic applications.

The successive ionic layer adsorption and reaction (SILAR) experimental process has been used to develop a high-efficiency electrode of MFe2O4 (M = Ni, Co and Mn) on substrates at ambient temperature. Structural, morphological and electrochemical properties have been investigated using x-ray diffraction (XRD), a scanning electron microscope (SEM) and an electrochemical test station, respectively. A morphology resembling the Hydrangea macrophylla flower has been observed and tuned with varying Fe concentration. The formation of MFe2O4 demonstrates the efficient electrochemical behavior and the specific capacitance has been evaluated as ∼1380, ∼972 and ∼815 Fg-1 for CoFe2O4 (CF), NiFe2O4 (NF) and MnFe2O4 (MF), respectively, at a current density of 1 Ag-1. Also, the developed electrodes maintain excellent cyclic retention of ∼92%, ∼89% and ∼86% for CF, NF, and MF, respectively, up to 5000 cycles. Further, asymmetric solid-state supercapacitor (ASC) devices have been fabricated using the best compositions of MFe2O4 as a positive electrode and carbon black (CB) as a negative electrode, and successfully illuminate a 1.8 V commercial LED.

We demonstrate a green, facile and rapid microwave-mediated process for fabricating carbon black (CB) incorporated Ni/Co hydroxide porous nanocomposites and study the effect of various mass loading of CB on supercapacitor performance. The structure and interactions between CB and Ni/Co hydroxide are characterized by using x-ray diffraction, Fourier-transform infrared spectroscopy and x-ray photoelectron spectroscopy, which suggest the miniaturization of the single-phase Ni/Co hydroxide formation time. A morphology study reveals that the addition of CB into Ni/Co hydroxide develops a loose network structure with well-defined architectural pores. In addition, the nanocomposites demonstrate noticeable improvements in porosity and atomic ratio of Ni/Co with an increasing percentage of carbon, which results in a higher diffusion of electrolytes, and hence electrical conduction. The developed electrode materials exhibit a maximum specific capacitance value of 1526 Fg-1 at current density 1 Ag-1 with excellent cyclic stability (92% retention at 5000 cycles), energy density (76 Wh Kg-1), power density (250 W Kg-1) and rate capability. A solid state asymmetric supercapacitor device is fabricated and utilized to brighten a commercial LED effectively for validating real usage.