Bharat Bade - Academia.edu (original) (raw)

Papers by Bharat Bade

4TH INTERNATIONAL CONFERENCE ON EMERGING TECHNOLOGIES; MICRO TO NANO, 2019: (ETMN 2019)

Hot injection method is well established and widely used technique for the synthesis of quantum d... more Hot injection method is well established and widely used technique for the synthesis of quantum dots and nanocrystals. In the present study, we report on size, shape, and phase controlled ZnSe nanocrystals, which were synthesized by facile hot injection method. For the synthesis, zinc sulfate heptahydrate is used as Zn precursor, Selenium powder is used as Se source and Oleylamine was as the capping ligand, stabilizer. The synthesized ZnSe nanocrystals were characterized by x-ray diffraction, Raman spectra, UV-Visible spectroscopy, and Photoluminescence spectroscopy. The x-ray diffraction confirms cubic zinc-blende crystal structure with orientation along (111) plane phase with 20 nm average crystalline size for ZnSe nanocrystals. The optical properties of ZnSe nanocrystals studied using UV-Visible and photoluminescence spectroscopy and obtained excitation wavelength 545 nm with estimated bandgap is 2.24 eV. The chemically prepared ZnSe nanocrystals are good candidate as buffer layer by replacing CdS in solar cell application.

Journal of Solid State Electrochemistry, 2021

Indium selenide (γ-In2Se3) films were prepared using RF magnetron sputtering. Influence of deposi... more Indium selenide (γ-In2Se3) films were prepared using RF magnetron sputtering. Influence of deposition time on structural, optical, morphological, and photoelectrochemical (PEC) performance was studied. Formation of γ-In2Se3 is confirmed by low angle XRD, Raman spectroscopy, and XPS analysis. Surface morphology investigated using FE-SEM shows that γ-In2Se3 films are uniform and have a dense grain structure, without cracks and holes. Optical properties show that γ-In2Se3films absorb mainly in the UV region, and the bandgap energy decreases from 2.81 to 2.27 eV as deposition duration increases. Conduction and valance band-edge potential values show that γ-In2Se3 films are suitable for photoelectrochemical hydrogen evolution. PEC activity of γ-In2Se3 photoanodes was evaluated using linear sweep voltammetry (LSV), and there was an increase in photocurrent density with deposition time. Electron impedance spectroscopy (EIS) analysis revealed that γ-In2Se3 photoanodes had high charge transf...

4TH INTERNATIONAL CONFERENCE ON EMERGING TECHNOLOGIES; MICRO TO NANO, 2019: (ETMN 2019), 2021

The Charge-discharge cycle performance of lead acid batteries has been analyzed in view of accura... more The Charge-discharge cycle performance of lead acid batteries has been analyzed in view of accurate estimation of state of charge at dynamic battery operations. In this article we report a constant current discharging method, on a Valve Regulated Lead Acid (VRLA) battery. The results show better performance with different discharging rates. The cyclic performance of the battery was carried out at different discharge rates. In the performance assessment, state of charge (SOC) have been estimated and correlated with coulomb counting method which resulted in close agreement.

Journal of emerging technologies and innovative research, 2019

Cadmium sulphide and cadmium zinc sulphide multilayer thin film was successfully deposited on gla... more Cadmium sulphide and cadmium zinc sulphide multilayer thin film was successfully deposited on glass substrate using chemical bath deposition (CBD) technique. Both groups II-VI compounds have semiconducting properties. In nano range the properties of the material changes and these properties can be used in improving many photovoltaic and opto-electronic devices. Thin films have many applications such as multilayer light emmiting diodes, photodetectors, gas sensors, thin film field effect transistors, optoelecronic modulators, electroluminescent devices etc. Variety of manufacture techniques have been used to fabricate thin films. Physical vapour deposition, spray pyrolysis, sputtering, spin coating, molecular beam epitaxy, thermal evaporation, chemical vapour deposition, electro-deposition, silar method, chemical bath method etc are some of the fabrication methods. The present invention relates to providing an improved method and product formed by the method for producing a cadmium sulphide and cadmium zinc sulphide multilayer thin film. Different solutions were prepared having a varying concentration of both cadmium sulphide and cadmium zinc sulphide. The composition of the thin film material is like first layer CdS, second layer(CdZn)S(80/20) and top most third layer (CdZn)S(50/50). The synthesized films are characterized by different techniques and properties are studied. The arrangement of the composite cascaded film will be proposed .The thickness measurement study is done by multiple beam interferometers. The thickness showed that the films prepared were getting deposited and were in the thin film range. The film thickness depends on the bath parameter like time duration for magnetic stirring, temperature and time duration for chemical bath. The thickness of the film is measured after each film deposition.The absorbance spectrum studies for the multilayer bulk thin film is better than mono layer and double layer thin film. The double layer nano thin film shows better absorbance spectrum than the mono layer nano thin film and multilayer nano thin film. Absorbance spectral study provided by UV-visible spectroscopy gives a measure of absorbance as a nature of band gap of semiconductor nano material and the value of band gap and particle size. The band gap energy of the CdS films was calculated and it was found to be as per the generalized results. The main objective of this work is to propose multilayer thin film for solar cell application. The band gap of the bulk and nano thin films has been calculated. The thin film has been proposed as an anti reflecting coating with less light absorption losses for solar cell application

CsPbI3 perovskite is the most suitable and desired bandgap among all-inorganic perovskite for sol... more CsPbI3 perovskite is the most suitable and desired bandgap among all-inorganic perovskite for solar cell applications. However, Poor phase stability is one of the biggest barriers in the further development of CsPbI3 perovskite solar cell. The direct room temperature synthesis is challenging because at room temperature it shows undesired orthorhombic (δ-CsPbI3) structure. Here, we have reported a low-temperature approach to synthesize CsPbI3. We did X-Ray diffraction (XRD) which confirms the formation of CsPbI3 material and also, we found the presence of both cubic and yellow phases. We have studied optical properties of CsPbI3 by measuring Photoluminescence (PL) and UV-visible absorption which shows both cubic (α-CsPbI3) and orthorhombic phase contributes in absorption spectra and also display the presence of a large amount of yellow phase in as-synthesized CsPbI3.

The copper oxide (CuO) nanostructures have been successfully synthesized from copper sulfate pent... more The copper oxide (CuO) nanostructures have been successfully synthesized from copper sulfate pentahydrate (CuSO4.5H2O) and NaOH as a stabilizing agent using simple hydrothermal chemical route. The prepared samples were characterized using x-ray diffraction, Raman spectroscopy, scanning electron microscopy, and UV-visible spectroscopy. The x-ray diffraction study of CuO nanostructures shows a monoclinic structure with average crystalline size 22 nm as calculated from the Debye-Scherrer’s equation. The hydrothermal technique used for the synthesis of CuO plays an important role in the formation of rod-like morphology. Optical study of CuO nanostructure facilitated estimation of bandgap to be 1.3 eV. The humidity sensing properties of CuO nanostructure are studied at a room temperature. The maximum sensitivity response was found to be 82.03 % which was stable and reproducible. The CuO nanostructures were successfully demonstrated as good candidate for humidity sensing application.

ES Energy & Environment

We report room temperature synthesis technique for the formamidinium lead iodide (FAPbI 3) perovs... more We report room temperature synthesis technique for the formamidinium lead iodide (FAPbI 3) perovskite. The low-cost sequential room temperature chemical synthesis technique resulted in formation of α-phase FAPbI 3 , suitable for solar cell absorber application. The chemical precursors formamidine acetate (CH 4 N 2 •xC 2 H 4 O 2) and lead iodide (PbI 2) were used in the process. The drop casted and spin coated films of FAPbI 3 on soda-lime glass and were then annealed at temperature of 80 °C. The FAPbI 3 materials films were characterized by X-ray diffraction, UV-Visible spectroscopy, photoluminescence (PL) measurements, and transmission electron microscopic (TEM) measurement. The X-ray diffraction pattern confirms α-phase of FAPbI 3 perovskite. The crystallite size as calculated from x-ray diffraction was found to be 40 nm corresponding to (001) peak. UV-Visible analysis shown broad absorption with bandgap value of 1.55 eV. The PL analysis show emission peak at 727 nm with estimated bandgap to be a 1.57 eV, in agreement with the UV-Visible spectroscopy. TEM analysis confirms the crystalline phase of FAPbI 3 material and the inter-planar spacing was deduced to be 0.62 nm. We conclude successful synthesis of FAPbI 3 perovskite with desirable properties in α-phase composition of FAPbI 3 that are suitable for solar cell application.

RSC Advances

Effect of solvent vapours on the micrometer and nanometre scale morphology of CH3NH3PbI3.

Journal of Solid State Electrochemistry

Herein, we report the synthesis of ZnO nanorod films onto FTO (fluorine-doped tin oxide) substrat... more Herein, we report the synthesis of ZnO nanorod films onto FTO (fluorine-doped tin oxide) substrates using the solution-processed electrodeposition method. As-synthesized ZnO nanorod films obtained from electrodeposition were modified to form zinc ferrite (ZnFe2O4) thin films by Fe incorporation through varying molar concentrations. The formation of ZnFe2O4 films was confirmed by XRD and Raman spectroscopy. FE-SEM analysis shows a significant change in the growth morphology with an increase in Fe molar concentration. UV-Visible spectroscopy analysis showed that with an increase in Fe molar concentration, the absorption edge in ZnFe2O4 films shifts towards a higher wavelength with a reduction in the direct band gap. Finally, the PEC properties of ZnFe2O4 photoanodes were investigated for water splitting. The highest photocurrent density of ~ 353 μA/cm2 has been observed for ZnFe2O4 photoanode prepared at 2.0 M. Shift of flat band potential shift from −0.25 to −0.61 V with an increase in Fe molar concentration indicates a shift in the Fermi level towards the conduction band, which leads to an efficient charge transfer process across the electrolyte. Furthermore, increased carrier density and decreased depletion width with increased Fe molar concentration suggest easier diffusion of photo-generated charge carriers. The obtained results demonstrate that ZnFe2O4 can be a promising candidate for efficient PEC water splitting over the traditional ZnO photoanode.

Materials Today: Proceedings

ES Materials & Manufacturing

Inorganic metal halide perovskites CsPbX3 (X = Cl, Br, and I) has achieved extensive attention in... more Inorganic metal halide perovskites CsPbX3 (X = Cl, Br, and I) has achieved extensive attention in recent years for photovoltaics because of their unique properties like tunable band gap, high charge carrier mobility, high absorption coefficient, etc. and which makes it suitable for optoelectronic applications. In this work, we have reported a facile synthesis method of inorganic CsPbBr3 nanoparticles (NPs) at room temperature using cesium bromide (CsBr) as a Cs source, lead bromide (PbBr2) as Br source, oleic acid, and Oleylamine as capping ligands. Nucleation starts immediately after the injection of a precursor solution into the toluene. Synthesis of CsPbBr3 NPs was confirmed by X-Ray diffraction pattern, UV-Visible spectroscopy, photoluminescence (PL), scanning electron microscopy (SEM), and atomic force microscopy (AFM). X-ray diffraction pattern reveals mainly the monoclinic crystal structure of CsPbBr3 NPs. The UV-Vis absorption spectra and PL spectra show a strong absorption peak at 509 nm, emission peak at 505 nm, and the band gap of CsPbBr3 to be 2.2 eV. The synthesized CsPbBr3 exhibit regular cuboid like structure with a particle size of approximately 400-500 nm. The surface roughness morphology of CsPbBr3 NPs was studied using AFM, and it shows the roughness of the CsPbBr3 films was around 260 nm. These results provide a facile synthesis method, and CsPbBr3 NPs are a suitable candidate for the optoelectronic and photovoltaic device's application.

Journal of Alloys and Compounds

Ternary Cu 2 SnS 3 (CTS) is an attractive nontoxic and earthabundant absorber material with suita... more Ternary Cu 2 SnS 3 (CTS) is an attractive nontoxic and earthabundant absorber material with suitable optoelectronic properties for costeffective photoelectrochemical applications. Herein, we report the synthesis of high-quality CTS nanoparticles (NPs) using a low-cost facile hot injection route, which is a very simple and nontoxic synthesis method. The structural, morphological, optoelectronic, and photoelectrochemical (PEC) properties and heterojunction band alignment of the as-synthesized CTS NPs have been systematically characterized using various state-of-the-art experimental techniques and atomistic first-principles density functional theory (DFT) calculations. The phase-pure CTS NPs confirmed by X-ray diffraction (XRD) and Raman spectroscopy analyses have an optical band gap of 1.1 eV and exhibit a random distribution of uniform spherical particles with size of approximately 15−25 nm as determined from high-resolution transmission electron microscopy (HR-TEM) images. The CTS photocathode exhibits excellent photoelectrochemical properties with PCE of 0.55% (fill factor (FF) = 0.26 and open circuit voltage (Voc) = 0.54 V) and photocurrent density of −3.95 mA/cm 2 under AM 1.5 illumination (100 mW/cm 2). Additionally, the PEC activities of CdS and ZnS NPs are investigated as possible photoanodes to create a heterojunction with CTS to enhance the PEC activity. CdS is demonstrated to exhibit a higher current density than ZnS, indicating that it is a better photoanode material to form a heterojunction with CTS. Consistently, we predict a staggered type-II band alignment at the CTS/CdS interface with a small conduction band offset (CBO) of 0.08 eV compared to a straddling type-I band alignment at the CTS/ZnS interface with a CBO of 0.29 eV. The observed small CBO at the type-II band aligned CTS/CdS interface points to efficient charge carrier separation and transport across the interface, which are necessary to achieve enhanced PEC activity. The facile CTS synthesis, PEC measurements, and heterojunction band alignment results provide a promising approach for fabricating next-generation Cu-based light-absorbing materials for efficient photoelectrochemical applications.

Engineered Science

Herein, we report the synthesis of different ZnO nanostructures using chemical bath deposition me... more Herein, we report the synthesis of different ZnO nanostructures using chemical bath deposition method by changing the molar concentration of zinc precursor. The synthesized films were characterized using X-ray diffraction, UV-Visible spectroscopy, and scanning electron microscopy for different physico-chemical characterization. The obtained ZnO nanostructures were sensitized with melanin. We found that melanin incorporation in ZnO nanostructures extended the absorbance spectra into visible region. The maximum photocurrent density was recorded with ZnO film deposited for the molar concentration of 0.2 M. The rise might be attributed to the increased specific surface area, crystallinity, charge transfer and reduced recombination losses. The effects of synthetic melanin dye on all the synthesized samples had also been studied for the photoelectrochemical (PEC) study. Melanin incorporated ZnO photo-anodes showed a photocurrent density about twice that of bare ZnO photo-anode under one sun illumination. The obtained results demonstrated that melanin incorporated ZnO can be considered as a potential material for photo-anodes for photosplitting of water.

Nanomaterials and Energy

Cadmium sulfide (CdS) nanoparticles were synthesized by using a simple and low-cost home-made hot... more Cadmium sulfide (CdS) nanoparticles were synthesized by using a simple and low-cost home-made hot-injection method at a low process temperature using different sulfur (S) sources. The effects of sulfur concentration on the structural, morphological and optoelectronic properties of the synthesized cadmium sulfide films were studied using a range of characterization techniques: X-ray diffraction (XRD), Raman spectroscopy, field-emission scanning electron microscopy (FESEM) and ultraviolet–visible spectroscopy. The XRD studies revealed the formation of hexagonal-type cadmium sulfide nanoparticles. The varying morphology dependence on the sulfur source was ascertained from FESEM analysis. The longitudinal optical phonon vibrational modes of cadmium sulfide were assigned in Raman spectra at 300 and 600 cm−1. The bandgap of the cadmium sulfide particles was estimated to be 2·30 eV from Tauc’s plots. Consistent with the experimental results, this study’s first-principles density functional...

SN Applied Sciences

Please note that this correction article itself should also be fully open access, with © The Auth... more Please note that this correction article itself should also be fully open access, with © The Author(s), open access grants:

Titanium dioxide (TiO 2) is a versatile and inexpensive material for extended applicability in se... more Titanium dioxide (TiO 2) is a versatile and inexpensive material for extended applicability in several scientific and technological fields including photo-catalysis for industrial waste treatment, energy harvesting, and hydrogen production. In this work, we report the synthesis of TiO 2 thin film using hydrothermal method and investigations on the influence of reaction time and annealing temperature on growth mechanism of the TiO 2 nanorods. The synthesized TiO 2 films were studied by using UV-visible spectroscopy, Raman spectroscopy, X-ray diffraction (XRD), scanning electron microscope and energy-dispersive X-ray spectroscopy (EDS). The XRD and Raman measurements revealed the formation of defect free and pure tetragonal TiO 2 rutile phase. The TiO 2 thin films show absorption band edge at around 420 nm in the UVvisible spectrum and exhibit direct band gap value of 2.9 eV. The TiO 2 nanorods are demonstrated to grow randomly on the FTO substrate with changing reaction times but grow uniformly in a flower-like pattern with increasing annealing temperature. Investigation of the field emission properties of TiO 2 thin films (tested as field-emitter array) estimates the turn-on and threshold field at 4.06 and 7.06 V/µm at 10 and 100 µA/cm 2 , respectively.