Android Based Bluetooth Appliance Control Mechanism 1

Abstract The proposed algorithm basically is an android application which possesses the capability to control any sort of electrical appliances remotely over the Bluetooth. The control mechanism mainly refers to the switching (on / off) of the appliances. It emphasizes on creating a virtual switch board, giving the user an exact experience of what he does regularly when switching off his bedroom lamp or his air -conditioner and for a lot of other household appliances

Charge Compensation Mechanism and Multifunctional Properties of Bi1-xBaxFeO3 (x=0, 0.05, 0.1) Ceramics

The charge compensation mechanism of Ba2+ ion doped BiFeO3 (BFO) has been studied here in detail. The most common problem of high leakage current of ceramic BFO was noticeably resolved by significant reduction of charge defects through Ba2+ doping. The leakage current density of Bi1-xBaxFeO3 (x = 0, 0.05, 0.1) was found to be reduced to similar to 3.13 x 10(-8) A cm(-2) for x = 0.1 from a value of 2.26 x 10(-4) A cm(-2) for x = 0 at an applied field of 500 V cm(-1). This reduction of leakage current was caused by the reduction of charge defects which was verified through the X-ray photoelectron spectroscopy (XPS). The dielectric and ferroelectric properties of undoped and Ba2+ doped BFO were also studied here explicitly and correlated with charge compensation mechanism. The structural and vibrational characterization proved the phase pure formation and the presence of metal-oxide bonds. The optical characterization showed the reduction in energy band gap with increased Ba2+ doping in BFO (2.18, 1.71 and 1.56 eV for x = 0, 0.05 and 0.1, respectively). Another common problem of BFO, namely low remanent magnetization, was also significantly resolved through Ba2+ doping in it and the strong antiferromagnetic BFO started showing weak ferromagnetic nature with increased doping concentration. (C) 2022 The Electrochemical Society (''ECS''). Published on behalf of ECS by IOP Publishing Limited

Barium titanate based paraelectric material incorporated Poly(vinylidene fluoride) for biomechanical energy harvesting and self-powered mechanosensing

Being a superior dielectric material exhibiting low loss, x = 0.4 composition of Ba1-xSrxTiO3 nanoparticles have been widely used as fillers in poly(vinylidene fluoride) (PVDF) for efficient flexible dielectric and electrical energy storage application. The mentioned composition of the material is also very attractive choice of interest to the researchers due to its ability of ferroelectric to paraelectric phase transition. Due to its paraelectric nature, Ba0.6Sr0.4TiO3 has not been used for mechanical energy harvesting application till date. Here we have used Ba0.6Sr0.4TiO3 particles as fillers in PVDF matrix for efficient mechanical energy harvesting purpose. In the present work, along with the flexible dielectric, ferroelectric and energy storage applications, the developed composite films have been explicitly used for efficient biomechanical energy harvesting, powering small elec-tronic devices and pressure sensing. The fabricated nanogenerator successfully generated a maximum output voltage and output power density of 15 V and 6.75 mu W/cm2 respectively on repeated human finger tapping. The obtained output power has been clearly explained on the basis of polar phase formation and consideration of stress concentration effect

Strategies Involved in Enhancing the Capacitive Energy Storage Characteristics of Poly(vinylidene fluoride) Based Flexible Composites

Functional Materials and Devices Division (FMDD) With the progress of the daily lifestyle of modern human being, the need for flexible dielectric energy storage devices for high field applications has become inevitable. PVDF and its co-polymers, which exhibit excellent flexibility, high breakdown strength, good piezoelectric and ferroelectric properties and low cost, have become very useful in this purpose and hence being investigated widely all over the world. Different strategies including versatile device fabrication techniques and momentous materials engineering have been employed to promote the energy storage characteristics of PVDF based composites. In this paper, we review the current trend of research in the field of PVDF based energy storage devices with the main focus on the strategies involved in enhancing their energy storage performance. Upon extensive literature survey, it has been found that the breakdown characteristics of the composite films are the main determining factor of their high field energy storage applications. The strategies, which can enhance the said performance of PVDF-based composites, have been elaborately discussed here step-by-step and the fruitful approaches for the desired performance enhancement have been proposed. Considering the numerous attraction of research in this field, the gaps and huge future scopes of research have also been comprehensively discussed here

Comprehensive characterization of Ba1-x,SrxTiO3: Correlation between structural and multifunctional properties

Considering the superior multifunctional performance and beautiful structural tunability, Ba(1- x)SrxTiO3 (0 <= x <= 1) samples were synthesized in this work by following a conventional solid state reaction technique. The structural, vibrational, optical and dielectric properties of the synthesized materials were characterized extensively throughout the work. Band gap energy of all the materials was evaluated from optical characterizations and correlated with structural properties. Study of leakage characteristics rendered fruitful explanation for electrical properties. At x = 0.4, a structural phase transition from ferroelectric to paraelectric state was observed. All the functional properties were correlated with structural properties. The Ba0.6Sr0.4TiO3 sample showed maximum room temperature dielectric permittivity (similar to 4000 at 1 kHz) with good frequency and thermal stability. The dielectric loss tangent of this composition was reduced to similar to 0.0098 (at 1 kHz) which was even much lower than that of undoped BaTiO3. The detail temperature dependent dielectric and impedance characteristics of this sample were also evaluated. The activation energy, calculated from dielectric characterizations, was found to be similar to 1 eV suggesting the governance of doubly ionized oxygen vacancy for conduction and relaxation mechanism. (C) 2021 Elsevier B.V. All rights reserved

Conducting polyaniline decorated in-situ poled Ferrite nanorod-PVDF based nanocomposite as piezoelectric energy harvester

PVDF-metal oxide based piezo-nanocomposite is an promising substitute of flexible nanogenerator. Herein, a ternary nanocomposite system Zinc Ferrite nanorod/Polyvinylidenefluoride (PVDF)/Polyaniline (PANI) nanochains was presented as alternative energy harvesting material. The inherent problem of low short-circuit current and high internal resistance of the nanocomposite was minimised by introducing a third phase cost-effective conducting supplementary filler, PANI nanochain.PANI assist to overcome the local dielectric dissimilarity by easy formation of conduction pathways via delocalization of pi-electrons present in the benzene ring and reduce the internal resistance of composite. Besides, it serves the role of dispersing agent by floating nanofillers throughout the volume and improves the homogeneity of filler distribution. Additionally, PANI reinforces composite with respect to stress accumulation and modulates the release behaviour by entangling with nanofillers by means of Van Der Waals force and helps to stabilize the polar PVDF. This lead to an improvement in electro-mechanical response and piezo-response behaviour of nanocomposite. The nanocomposite exhibits a similar to 42 V ac open circuit voltage and short circuit current density similar to 0.85 mu A/cm(2) with an overall increase in power density 35% compare to its binary metal-oxide/PVDF nanocomposite counterpart in response to single finger tapping and releasing. The generated power was utilized to illuminate twenty six number of red LEDs without any external energy storage unit. Also, the nanocomposite could charge up a commercial capacitor (10 mu F) within 115 s which can be used for alternative powersource in self-powered devices and sensors. (C) 2019 Published by Elsevier B.V

Role of suppressed oxygen vacancies in the BiFeO3 nanofiller to improve the polar phase and multifunctional performance of poly(vinylidene fluoride)

In the present work, we report the enhanced dielectric, ferroelectric, energy storage and energy harvesting performance of a citrate-gel synthesized Bi1-xBaxFeO3 (x = 0, 0.05, 0.10) incorporated poly(vinylidene fluoride) (PVDF) matrix. Doping with aliovalent ions has been shown to improve the multiferroic properties of BiFeO3. Though Ba2+ doping has been expected to introduce more oxygen vacancies, here we found a decrease in oxygen vacancies with increasing Ba2+ up to 10% doping. This suppression of oxygen vacancies through Ba2+ doping in BiFeO3 helped in the formation of the polar PVDF phase in the composite through interfacial interaction. The polar phase fraction (F(EA)) increases to 82.4% for the 7 wt% Bi0.9Ba0.1FeO3 incorporated PVDF film from 38.2% for the neat PVDF. This film also showed the highest energy storage density of 5.4 mJ cm(-3) at a 110 kV cm(-1) applied field and the highest energy harvesting performance of approximate to 20 V open circuit output voltage after application of repeated human finger tapping and releasing motion, due to its enhanced piezoelectric property. Here, we also demonstrate the enhanced energy harvesting capability of the said PVDF-Bi0.9Ba0.1FeO3 composite by charging a 10 F commercial capacitor up to approximate to 5 V in 270 s, which can comfortably light up about 50 LEDs instantaneously

Significantly suppressed leakage current and reduced band gap of BiFeO3 through Ba-Zr Co-Substitution: Structural, optical, electrical and magnetic study

Bismuth Ferrite (BFO), Ba substituted BFO (BBFO) and Ba-Zr co-substituted BFO (BBFZO) nanoparticles have been synthesized via citrate-gel route. The common problem of BFO i.e; compositional instability, low magnetization and high leakage current was resolved by this doping technique. Remanent magnetization and remanent polarization improved significantly for BBFZO sample compared to that of BFO. Structural, optical and improved dielectric properties were also investigated. Structural study confirmed the enhanced structural distortion in BFO due to doping of Ba and Ba-Zr ions. The calculated energy band gap has been reduced to 1.52 eV for BBFZO nanoparticles from a value of 2.55 eV for BFO. Leakage current was suppressed by almost seven orders of magnitude for Ba-Zr co-substituted bulk BFO compared to that of undoped BFO. Morphological study of bulk samples has shown gradual reduction in grain size upon Ba doping and Ba-Zr co-doping in BFO, respectively

Synthesis and characterization of SmFeO3 and its effect on the electrical and energy storage properties of PVDF

Here we report an anomalous electrical properties and energy storage performance of SmFeO3-Poly(vinylidene fluoride) (SFO-PVDF) composites fabricated by a simple solvent casting technique with SmFeO3 concentration varying from 1 to 10 wt% with respect to PVDF content. Dielectric permittivity and ferroelectric parameters of PVDF initially decreased for 1 wt% SmFeO3 incorporation and then started increasing with further increase of SFO concentration. However, in contrary to our expectation, all the composites exhibited lower values of dielectric permittivity compared to neat PVDF. The observed unexpected trend of variation of dielectric permittivity and electric displacement was explained by considering a local electric field approximation model followed by the mechanism of polymer chain movement and dipole orientation of PVDF