Advanced Materials and Devices : [251]

Follow this collection to receive daily e-mail notification of new additions
Collection's Items (Sorted by Submit Date in Descending order): 1 to 20 of 251
  • V2O5 nanoparticles as cathode for lithium-ion battery applications_ Fabricated via microwave-assisted green synthesis using A. paniculata leaf extract.pdf.jpg
  • Article


  • Authors: Karthik, K.; Phuruangrat, Anukorn; Chowdhury, Zaira Zaman; Pradeeswari, K.; Kumar, R. Mohan (2019)

  • Vanadium pentoxide (V2O5) cathode was fabricated via a facile simple and microwave-assisted method by the utilization of Andrographis paniculata leaf extract as fuel and optimizes the electrochemical applications. Structural and surface morphology of V2O5 nanoparticles was analyzed by various spectroscopic techniques like SEM and TEM. The PXRD exhibits an orthorhombic crystal structure with an average crystallite size (32 nm). The band at 497 cm-1 is attributed to V-O-V stretching vibration through FTIR analysis. The electrochemical characterization of synthesized V2O5 nanoparticles was studied towards the lithium-ion battery applications. Various parameters like Charge-Discharge, Cyc...

  • The TiO2-graphene oxide-Hemin ternary hybrid composite material as an efficient heterogeneous catalyst for the degradation of organic contaminants.pdf.jpg
  • Article


  • Authors: Munikrishnappa, C.; Kumar, Surender; Shivakumara, S.; Rao, G. Mohan; Munichandraiah, N. (2019)

  • TiO2-Graphene Oxide-Hemin (TiO2/GO/Hemin) ternary composite hybrid material was prepared by the sol-gel method and used as a heterogeneous catalyst for the photocatalytic degradation of organic contaminants. The catalytic activity of GO-TiO2-Hemin was evaluated by the degradation of Rhodamine B (RhB) under the UV-visible light irradiation and in the presence of hydrogen peroxide. The ternary composite of (TiO2/GO/Hemin) shows an excellent activity over a wide pH range from 3 to 11 and also a stable catalytic activity after five recycles. The increase in the efficiency of TiO2-GO-Hemin-UV processes is attributed to the Fe2þ ions produced from the cleavage of stable iron complexes, whic...

  • The electrochemical behavior, antifungal and cytotoxic activities of phytofabricated MgO nanoparticles using Withania somnifera leaf extract.pdf.jpg
  • Article


  • Authors: Raveesha, H.R.; Nayana, S.; Vasudha, D.R.; Begum, J.P. Shabaaz; Pratibha, S.; Ravikumara, C.R.; Dhananjaya, N. (2019)

  • Magnesium oxide nanoparticles (MgO NPs) without and with Ca, Eu dopant were synthesized by using the W. somnifera leaf extract through the low temperature green combustion method. The detailed analytical characterizations such as Powder X-Ray Diffraction (PXRD), Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS), Transmission Electron Microscopy (TEM), Fourier Transform-infrared Spectra (FTIR), etc. have been carried out for the obtained NPs. The PXRD patterns confirmed the formation of the Periclase structure with the cubic phase whereas the SEM and TEM results revealed the agglomerated roughly spherical granular structures of about 50e70 nm in size. FTIR spectr...

  • Synthesis of silver promoted CuMnOx catalyst for ambient temperature oxidation of carbon monoxide.pdf.jpg
  • Article


  • Authors: Dey, Subhashish; Dhal, Ganesh Chandra; Mohan, Devendra; Prasad, Ram (2019)

  • The present research shows that the addition of silver (Ag), by the deposition-precipitation method, to a mixed CuMnOx catalyst can improve the activity of carbon monoxide (CO) oxidation. The CuMnOx catalyst doped with 3 wt.% Ag shows a higher catalytic activity as compared to the 1, 2, 4 and 5 wt.% Ag doped samples. The loading of Ag could introduce new active sites into the CuMnOx catalyst and reduce its deactivation. The order of the optimal calcination strategies based on the performance of catalysts for CO oxidation is as follows: Reactive Calcination > Flowing air > Stagnant air. All the catalysts were characterized by XRD, FTIR, BET, XPS and SEM-EDX techniques. It was found tha...

  • Synthesis and characterization of a clay-alginate nanocomposite for the controlled release of 5-Flurouracil.pdf.jpg
  • Article


  • Authors: Surya, R.; Mullassery, Manohar D.; Fernandez, Noeline B.; Thomas, Diana (2019)

  • The scope of the present study is the synthesis and characterization of a nanocomposite based on natural bentonite clay and sodium alginate as a drug delivery system. The nanocomposite was prepared by the grafted copolymerization of alginate, acrylamide and modified bentonite. The characterization of the nanocomposite was carried out using FTIR, XRD, SEM, TG/DTA, Zeta potential, DLS and TEM analysis. A hydrophilic anticancer drug 5-Flurouracil was chosen as the model drug to investigate the loading and release of the nanocomposite. Swelling profile study revealed that maximum swelling was occurred at pH 6.8. The fitting of Peppas's kinetic model was analysed at pH 6.8 and the release ...

  • Sunlight photocatalytic performance of Mg-doped nickel ferrite synthesized by a green sol-gel route.pdf.jpg
  • Article


  • Authors: Nadumane, Aparna; Shetty, Krushitha; Anantharaju, K.S.; Nagaswarupa, H.P; Rangappa, Dinesh; Vidya, Y.S.; Nagabhushana, H.; Prashantha, S.C. (2019)

  • We report an environmentally friendly synthetic strategy to synthesize new nickel ferrite and Mg doped nickel ferrite photocatalysts under modified green sol-gel route in which Aloe Vera gel acts as a natural template. The crystalline phase, surface morphology and size of the prepared photocatalysts were characterized by PXRD, SEM, TEM and HRTEM analysis. The energy band gap of the nanoparticles (NPs) can be tuned in the range of 2.55e2.34 eV by varying the dopant concentration. The photoluminescence analysis indicates that the present NPs are an effective white component in display applications. These synthesized NPs were used for photocatalytic decomposition of recalcitrant polluta...

  • Study of modified PEDOT_PSS for tuning the optical properties of its conductive thin films.pdf.jpg
  • Article


  • Authors: Singh, Vinamrita; Kumar, Tanuj (2019)

  • The present work focuses on studying the optical properties of the pristine PEDOT:PSS and the PEDOT:PSS modified with de-ionized water, ethylene glycol and MWCNT. The effect of various additives on the absorption, the refractive index, and the dielectric constant has been inspected. The refractive index dispersion has been analyzed using the single oscillator model developed by Wemple and DiDomenico. The optical constants, such as the dispersion energy, the single oscillator energy, the average oscillator strength, the average interband oscillator strength, the long wavelength refractive index, and the plasma resonance frequency have been determined. The energy bandgap was found redu...

  • Study of interfaces in polymer-metal oxide films and free-volume hole using low-energy positron lifetime measurements.pdf.jpg
  • Article


  • Authors: Acharya, Aman Deep; Sarwan, Bhawna; Sharma, Ratnesh; Shrivastava, S.B.; Rathore, Manoj Kumar (2019)

  • To reveal how the distribution of different nano fillers affect the UV-shielding efficiency of their polymerbased composites and to further develop a simple strategy to refrain the erection of the composites, we prepared ZnO doped polystyrene (PS/ZnO) and TiO2 doped polystyrene (PS/TiO2) films by the solution cast technique with different concentrations of ZnO and TiO2 (0.25%, 0.5%, 0.75% and 1%.). Contrary to the common observation, the better tunability for UV shielding efficiency was found in case of TiO2 as compared to ZnO. This is mainly due to the appearance of a rod like structure on neat PS which has improved the dispersion as well as provides a higher interface area that enh...

  • Studies of proton conducting polymer electrolyte based on PVA, amino acid proline and NH4SCN.pdf.jpg
  • Article


  • Authors: Hemalatha, R.; Alagar, M.; Selvasekarapandian, S.; Sundaresan, B.; Moniha, V. (2019)

  • Proton conducting polymer electrolytes based on PVA, amino acid proline and NH4SCN were prepared by the solution casting technique. An increase in the amorphous nature of the polymer electrolytes was confirmed by X-ray diffraction analysis. DSC measurements showed a decrease in Tg with increasing salt concentration. The complex formation of the PVA/Proline/NH4SCN was investigated by FTIR analysis. The highest ionic conductivity of 1.17 10-3 S/cm for the 75 Mwt% PVA: 25 Mwt% Proline: 0.5 Mwt% of NH4SCN polymer electrolyte at ambient temperature was obtained by using AC impedance technique. Transference number measurements revealed the nature of the charge transport species in the pol...

  • Structural, optical, magnetic and thermal investigations on Cr3+ ions doped ZnS nanocrystals by co-precipitation method.pdf.jpg
  • Article


  • Authors: Basha, Sk. Johny; Khidhirbrahmendra, V.; Madhavi, J.; Thampy, U.S. Udayachandran; Reddy, Ch. Venkata; Ravikumar, R.V.S.S.N. (2019)

  • Cr3þ ions doped ZnS nanocrystals were synthesized using the co-precipitation method. The as-prepared sample was characterized to investigate the magnetic and thermal properties along with its structural and spectral studies. X-ray diffraction (XRD) analysis confirms the cubic zinc blend structure, and the mean crystallite size is evaluated to be 4.7 nm. Scanning electron microscope (SEM) and transmission electron microscopy (TEM) images indicate stone-like structures. The deposition of Cr3þ ions in ZnS nanocrystals is evidenced by energy dispersive spectroscopy (EDS) analysis. From the optical absorption data, the bands in the UV-VIS region are recognized as the characteristic bands ...

  • Structural, optical and electrical properties of Ni(II)-2,2-bipyridine complexes thin films deposited on glass substrates.pdf.jpg
  • Article


  • Authors: Mamine, Hadjer; Bendjeffal, Hacene; Metidji, Toufek; Djebli, Abdelkrim; Rebbani, Nacer; Bouhedja, Yacine (2019)

  • The present study was mainly designed to prepare thin layers based on hybrid materials deposited on glass substrates. Herein, the Ni(II)-2,2-bipyridine complexes thin films have been elaborated following a successive ionic layer adsorption and reaction process as a simple and low-cost chemical technique. The deposition experiments were performed on glass substrates under the effect of several physicochemical factors, including dipping cycles (30e120 cycles), variations in solution temperature (293e323 K) and in precursor concentrations (10 3e10 1 mol L 1), as well as the effect of the counter-anions [Fe(CN)5NO] 2 and [Ag(CN)2] . The synthesized films were characterized using scanning...

  • Structural, electrical and magnetic properties of Mg-Zr co-substituted Ni0.5Zn0.5Fe2O4.pdf.jpg
  • Article


  • Authors: Jalaiah, K.; Mouli, K. Chandra; Babu, K. Vijaya; Krishnaiah, R.V. (2019)

  • Zr and Mg co-substituted Ni0.5Zn0.5Fe2O4 ferrites have been synthesized by the sol-gel auto-combustion method. The X-ray diffraction patterns evidenced the single phase cubic spinel structure. The lattice parameter and cell volume are in resemblance trend with the variation of the dopant concentration. The similar trend is observed for the crystallite and particle size. The porosity and sintered density, however, vary in an opposite way with a variation of the dopant concentration. The same variation is found for the drift mobility and DC resistivity. The Arrhenius graphs of DC resistivity exhibit the semiconductor nature, for which the activation energy decreased with increasing the ...

  • Structural characterization and corrosion properties of electroless processed NiPMnO2 composite coatings on SAE 1015 steel for advanced applications.pdf.jpg
  • Article


  • Authors: Fayomi, O.S.I.; Akande, I.G.; Popoola, A.P.I.; Popoola, S.I.; Daramola, D. (2019)

  • In recent years, electroless NieP coatings with the incorporation of metallic oxides have received profound interest due to their unique properties and ability to enhance the operational performance of the base metal. These coatings have been utilised for numerous applications such as aerospace, automotive and industrial field where materials with exceptional qualities are required. This present work focuses on the improvement of the surface characteristics of mild steel via the electroless deposition of Nie- PeMnO2. The deposition was achieved by varying the mass concentration of MnO2 at fixed temperature and deposition time of 85 C and 20 min, respectively. The examinations of the ...

  • Statistical optimization of activated carbon from Thapsia transtagana stems and dyes removal efficiency using central composite design.pdf.jpg
  • Article


  • Authors: Machrouhi, A.; Alilou, H.; Farnane, M.; El Hamidi, S.; Sadiq, M.; Abdennouri, M.; Tounsadi, H.; Barka, N. (2019)

  • This study focused on the preparation of activated carbons from Thapsia transtagana stems by boric acid activation and their evaluation for dyes removal. Central composite design and response surface methodology were used to optimize the preparation conditions. The effect of activation temperature, impregnation ratio and activation time on iodine number (IN), methylene blue index (MB index) and removal efficiencies of methyl violet (MV), methyl orange (MO) and indigo carmine (IC) were fully evaluated. Activated carbon samples prepared in optimal conditions were characterized by FTIR, XRD, SEM-EDX, Boehm’s titration, and point of zero charge (pHPZC). The equilibrium data for dyes sor...

  • Spectroscopic, thermal, structural and electrical studies on VO2+ ions doped PVA_MAA_EA polymer blend films.pdf.jpg
  • Article


  • Authors: Pravakar, Ojha; Siddaiah, T.; Ramacharyulu, P.V.R.K.; Gopal, N.O.; Ramu, Ch.; Nagabhushana, H. (2019)

  • Pure and VO2þ ions doped PVA/MAA:EA polymer blend films were prepared by a solution casting method. XRD pattern reveals an increase in amorphicity with increase in doping. The dTGA study shows an enhancement of thermal stability of the system with increase in dopant concentration. The optical absorption spectrum exhibits three bands corresponding to the transitions 2B2g/2A1g, 2B2g/2B1g and 2B2g/2Eg, characteristic of VO2þ ions in octahedral symmetry with tetragonal distortion and reflects that the optical band gap decreases with the increase of mol% of VO2þ. EPR spectra of all the doped samples show a characteristic eightline hyperfine structure of VO2þ ions, which arises due to the i...

  • Simulation studies on the responses of ZnO-CuO_CNT nanocomposite based SAW sensor to various volatile organic chemicals.pdf.jpg
  • Article


  • Authors: Abraham, Nelsa; Krishnakumar, R. Reshma; Unni, C.; Philip, Daizy (2019)

  • Surface acoustic wave (SAW) sensors offer a sensitive platform for monitoring important physical entities with several advantages. They can operate well in extreme conditions such as high temperature, high pressure and toxic environment. This work presents a 2D model of SAW sensor with carbon nano tubes (CNT) as the adsorbent material. A second model was also created by incorporating ZnO and CuO nanospheres into the sensing layer. The responses of the two sensors towards various gases were analysed at room temperature. The design was modelled and analysed using COMSOL Multiphysics software which applies the finite element analysis to solve for Eigen frequencies. The shift in the reson...

  • Sensing properties of sulfonated multi-walled carbon nanotube and graphene nanocomposites with polyaniline.pdf.jpg
  • Article


  • Authors: Khan, Mahfoozurrahman; Anwer, Tarique; Mohammad, Faiz (2019)

  • Here, we discuss one of the simplest approaches for chemical functionalization of in-situ prepared polyaniline (Pani) and its nanocomposites with multi-walled carbon nanotubes (MWCNT) and graphene (GN) in chlorosulphonic acid. The effect of polymerization and functionalization was characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) analysis, Field emission scanning electron microscopy (FESEM) and electro-thermal analysis. Results also revealed the presence of p p interactions between Pani and carbon allotropes leading to the formation of charge-transfer complexes. This strong p p interaction significantly increased the resultant electrical conducti...

  • Role of graphene nanofluids on heat transfer enhancement in thermosyphon.pdf.jpg
  • Article


  • Authors: Das, Sidhartha; Giri, Asis; Samanta, Sutanu; Kanagaraj, S. (2019)

  • The thermophysical properties of graphene nanofluids in thermosyphon have been studied at different power inputs, temperatures and angles of inclination. The thermal conductivity of the graphene nanofluid is found to be 29% higher than that of the deionized water at 45 C. The viscosity of the graphene nanofluid increased with the concentration of graphene nanoparticles and decreased with increasing the temperature. It is observed that the wall temperature distribution of graphene nanofluid is found to be decreased in comparison to that of deionised water. The thermal resistance of thermosyphon is reduced with increasing the power input and irrespective of the inclination angle

  • Role of electronegativity on the bulk modulus, magnetic moment and band gap of Co2MnAl based Heusler alloys.pdf.jpg
  • Article


  • Authors: Kumar, Author-Shiv Om; Shukla, Vineeta; Srivastava, Sanjeev Kumar (2019)

  • In this paper, we have presented the comparative study of mechanical, electrical and magnetic properties of Co2MnAl1 xZx Heusler alloy with Z ¼ Si, Ge and Ga and x ¼ 0, 0.25, 0.75 and 1 using electronegativity (EN) model. We employed density functional theory for numerical calculations. It is found that Co2MnAl1 xZx with Z ¼ Ga, Ge follow the Vegard's law while Co2MnAl1 xSix does not follow the same trend. Among all composition Co2MnAl.25Si.75 alloy is found to be more compressible. Electronic density distribution depicts the ionic nature of Co2MnAl1 xZx alloy systems. The Co2MnAl1 xZx with Z ¼ Si, Ge possess larger magnetic moment and band gap with respect to Co2MnAl1 xGax system wh...

  • Role of Co dopants on the structural, optical and magnetic properties of lead-free ferroelectric Na0.5Bi0.5TiO3 materials.pdf.jpg
  • Article


  • Authors: Dung, D.D.; Doan, N.B.; Dung, N.Q.; Bac, L.H.; Linh, N.H.; Thanh, L.T.H.; Thiet, D.V.; Trung, N.N.; Khang, N.C.; Trung, T.V.; Duc, N.V. (2019)

  • Co-doped Na0.5Bi0.5TiO3 materials were fabricated by a sol-gel technique. The structural distortion of Codoped Na0.5Bi0.5TiO3 materials was due to the difference between the radii of Co dopants and Ti hosts. The optical band gap decreased from 3.11 to 1.83 eV because of the local state of the Co cation in the band structure. Room temperature ferromagnetism emerged as compensation of diamagnetic background and possibly intrinsic ferromagnetic signals. The magnetic moment was determined to be ~0.64 mB/Co at 5 K. The origin of the room temperature ferromagnetism in the Co-doped Na0.5Bi0.5TiO3 materials was also investigated through the first-principles calculation method. Our study provi...

Collection's Items (Sorted by Submit Date in Descending order): 1 to 20 of 251

Advanced Materials and Devices : [251]

Follow this collection to receive daily e-mail notification of new additions
Collection's Items (Sorted by Submit Date in Descending order): 1 to 20 of 251
  • V2O5 nanoparticles as cathode for lithium-ion battery applications_ Fabricated via microwave-assisted green synthesis using A. paniculata leaf extract.pdf.jpg
  • Article


  • Authors: Karthik, K.; Phuruangrat, Anukorn; Chowdhury, Zaira Zaman; Pradeeswari, K.; Kumar, R. Mohan (2019)

  • Vanadium pentoxide (V2O5) cathode was fabricated via a facile simple and microwave-assisted method by the utilization of Andrographis paniculata leaf extract as fuel and optimizes the electrochemical applications. Structural and surface morphology of V2O5 nanoparticles was analyzed by various spectroscopic techniques like SEM and TEM. The PXRD exhibits an orthorhombic crystal structure with an average crystallite size (32 nm). The band at 497 cm-1 is attributed to V-O-V stretching vibration through FTIR analysis. The electrochemical characterization of synthesized V2O5 nanoparticles was studied towards the lithium-ion battery applications. Various parameters like Charge-Discharge, Cyc...

  • The TiO2-graphene oxide-Hemin ternary hybrid composite material as an efficient heterogeneous catalyst for the degradation of organic contaminants.pdf.jpg
  • Article


  • Authors: Munikrishnappa, C.; Kumar, Surender; Shivakumara, S.; Rao, G. Mohan; Munichandraiah, N. (2019)

  • TiO2-Graphene Oxide-Hemin (TiO2/GO/Hemin) ternary composite hybrid material was prepared by the sol-gel method and used as a heterogeneous catalyst for the photocatalytic degradation of organic contaminants. The catalytic activity of GO-TiO2-Hemin was evaluated by the degradation of Rhodamine B (RhB) under the UV-visible light irradiation and in the presence of hydrogen peroxide. The ternary composite of (TiO2/GO/Hemin) shows an excellent activity over a wide pH range from 3 to 11 and also a stable catalytic activity after five recycles. The increase in the efficiency of TiO2-GO-Hemin-UV processes is attributed to the Fe2þ ions produced from the cleavage of stable iron complexes, whic...

  • The electrochemical behavior, antifungal and cytotoxic activities of phytofabricated MgO nanoparticles using Withania somnifera leaf extract.pdf.jpg
  • Article


  • Authors: Raveesha, H.R.; Nayana, S.; Vasudha, D.R.; Begum, J.P. Shabaaz; Pratibha, S.; Ravikumara, C.R.; Dhananjaya, N. (2019)

  • Magnesium oxide nanoparticles (MgO NPs) without and with Ca, Eu dopant were synthesized by using the W. somnifera leaf extract through the low temperature green combustion method. The detailed analytical characterizations such as Powder X-Ray Diffraction (PXRD), Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS), Transmission Electron Microscopy (TEM), Fourier Transform-infrared Spectra (FTIR), etc. have been carried out for the obtained NPs. The PXRD patterns confirmed the formation of the Periclase structure with the cubic phase whereas the SEM and TEM results revealed the agglomerated roughly spherical granular structures of about 50e70 nm in size. FTIR spectr...

  • Synthesis of silver promoted CuMnOx catalyst for ambient temperature oxidation of carbon monoxide.pdf.jpg
  • Article


  • Authors: Dey, Subhashish; Dhal, Ganesh Chandra; Mohan, Devendra; Prasad, Ram (2019)

  • The present research shows that the addition of silver (Ag), by the deposition-precipitation method, to a mixed CuMnOx catalyst can improve the activity of carbon monoxide (CO) oxidation. The CuMnOx catalyst doped with 3 wt.% Ag shows a higher catalytic activity as compared to the 1, 2, 4 and 5 wt.% Ag doped samples. The loading of Ag could introduce new active sites into the CuMnOx catalyst and reduce its deactivation. The order of the optimal calcination strategies based on the performance of catalysts for CO oxidation is as follows: Reactive Calcination > Flowing air > Stagnant air. All the catalysts were characterized by XRD, FTIR, BET, XPS and SEM-EDX techniques. It was found tha...

  • Synthesis and characterization of a clay-alginate nanocomposite for the controlled release of 5-Flurouracil.pdf.jpg
  • Article


  • Authors: Surya, R.; Mullassery, Manohar D.; Fernandez, Noeline B.; Thomas, Diana (2019)

  • The scope of the present study is the synthesis and characterization of a nanocomposite based on natural bentonite clay and sodium alginate as a drug delivery system. The nanocomposite was prepared by the grafted copolymerization of alginate, acrylamide and modified bentonite. The characterization of the nanocomposite was carried out using FTIR, XRD, SEM, TG/DTA, Zeta potential, DLS and TEM analysis. A hydrophilic anticancer drug 5-Flurouracil was chosen as the model drug to investigate the loading and release of the nanocomposite. Swelling profile study revealed that maximum swelling was occurred at pH 6.8. The fitting of Peppas's kinetic model was analysed at pH 6.8 and the release ...

  • Sunlight photocatalytic performance of Mg-doped nickel ferrite synthesized by a green sol-gel route.pdf.jpg
  • Article


  • Authors: Nadumane, Aparna; Shetty, Krushitha; Anantharaju, K.S.; Nagaswarupa, H.P; Rangappa, Dinesh; Vidya, Y.S.; Nagabhushana, H.; Prashantha, S.C. (2019)

  • We report an environmentally friendly synthetic strategy to synthesize new nickel ferrite and Mg doped nickel ferrite photocatalysts under modified green sol-gel route in which Aloe Vera gel acts as a natural template. The crystalline phase, surface morphology and size of the prepared photocatalysts were characterized by PXRD, SEM, TEM and HRTEM analysis. The energy band gap of the nanoparticles (NPs) can be tuned in the range of 2.55e2.34 eV by varying the dopant concentration. The photoluminescence analysis indicates that the present NPs are an effective white component in display applications. These synthesized NPs were used for photocatalytic decomposition of recalcitrant polluta...

  • Study of modified PEDOT_PSS for tuning the optical properties of its conductive thin films.pdf.jpg
  • Article


  • Authors: Singh, Vinamrita; Kumar, Tanuj (2019)

  • The present work focuses on studying the optical properties of the pristine PEDOT:PSS and the PEDOT:PSS modified with de-ionized water, ethylene glycol and MWCNT. The effect of various additives on the absorption, the refractive index, and the dielectric constant has been inspected. The refractive index dispersion has been analyzed using the single oscillator model developed by Wemple and DiDomenico. The optical constants, such as the dispersion energy, the single oscillator energy, the average oscillator strength, the average interband oscillator strength, the long wavelength refractive index, and the plasma resonance frequency have been determined. The energy bandgap was found redu...

  • Study of interfaces in polymer-metal oxide films and free-volume hole using low-energy positron lifetime measurements.pdf.jpg
  • Article


  • Authors: Acharya, Aman Deep; Sarwan, Bhawna; Sharma, Ratnesh; Shrivastava, S.B.; Rathore, Manoj Kumar (2019)

  • To reveal how the distribution of different nano fillers affect the UV-shielding efficiency of their polymerbased composites and to further develop a simple strategy to refrain the erection of the composites, we prepared ZnO doped polystyrene (PS/ZnO) and TiO2 doped polystyrene (PS/TiO2) films by the solution cast technique with different concentrations of ZnO and TiO2 (0.25%, 0.5%, 0.75% and 1%.). Contrary to the common observation, the better tunability for UV shielding efficiency was found in case of TiO2 as compared to ZnO. This is mainly due to the appearance of a rod like structure on neat PS which has improved the dispersion as well as provides a higher interface area that enh...

  • Studies of proton conducting polymer electrolyte based on PVA, amino acid proline and NH4SCN.pdf.jpg
  • Article


  • Authors: Hemalatha, R.; Alagar, M.; Selvasekarapandian, S.; Sundaresan, B.; Moniha, V. (2019)

  • Proton conducting polymer electrolytes based on PVA, amino acid proline and NH4SCN were prepared by the solution casting technique. An increase in the amorphous nature of the polymer electrolytes was confirmed by X-ray diffraction analysis. DSC measurements showed a decrease in Tg with increasing salt concentration. The complex formation of the PVA/Proline/NH4SCN was investigated by FTIR analysis. The highest ionic conductivity of 1.17 10-3 S/cm for the 75 Mwt% PVA: 25 Mwt% Proline: 0.5 Mwt% of NH4SCN polymer electrolyte at ambient temperature was obtained by using AC impedance technique. Transference number measurements revealed the nature of the charge transport species in the pol...

  • Structural, optical, magnetic and thermal investigations on Cr3+ ions doped ZnS nanocrystals by co-precipitation method.pdf.jpg
  • Article


  • Authors: Basha, Sk. Johny; Khidhirbrahmendra, V.; Madhavi, J.; Thampy, U.S. Udayachandran; Reddy, Ch. Venkata; Ravikumar, R.V.S.S.N. (2019)

  • Cr3þ ions doped ZnS nanocrystals were synthesized using the co-precipitation method. The as-prepared sample was characterized to investigate the magnetic and thermal properties along with its structural and spectral studies. X-ray diffraction (XRD) analysis confirms the cubic zinc blend structure, and the mean crystallite size is evaluated to be 4.7 nm. Scanning electron microscope (SEM) and transmission electron microscopy (TEM) images indicate stone-like structures. The deposition of Cr3þ ions in ZnS nanocrystals is evidenced by energy dispersive spectroscopy (EDS) analysis. From the optical absorption data, the bands in the UV-VIS region are recognized as the characteristic bands ...

  • Structural, optical and electrical properties of Ni(II)-2,2-bipyridine complexes thin films deposited on glass substrates.pdf.jpg
  • Article


  • Authors: Mamine, Hadjer; Bendjeffal, Hacene; Metidji, Toufek; Djebli, Abdelkrim; Rebbani, Nacer; Bouhedja, Yacine (2019)

  • The present study was mainly designed to prepare thin layers based on hybrid materials deposited on glass substrates. Herein, the Ni(II)-2,2-bipyridine complexes thin films have been elaborated following a successive ionic layer adsorption and reaction process as a simple and low-cost chemical technique. The deposition experiments were performed on glass substrates under the effect of several physicochemical factors, including dipping cycles (30e120 cycles), variations in solution temperature (293e323 K) and in precursor concentrations (10 3e10 1 mol L 1), as well as the effect of the counter-anions [Fe(CN)5NO] 2 and [Ag(CN)2] . The synthesized films were characterized using scanning...

  • Structural, electrical and magnetic properties of Mg-Zr co-substituted Ni0.5Zn0.5Fe2O4.pdf.jpg
  • Article


  • Authors: Jalaiah, K.; Mouli, K. Chandra; Babu, K. Vijaya; Krishnaiah, R.V. (2019)

  • Zr and Mg co-substituted Ni0.5Zn0.5Fe2O4 ferrites have been synthesized by the sol-gel auto-combustion method. The X-ray diffraction patterns evidenced the single phase cubic spinel structure. The lattice parameter and cell volume are in resemblance trend with the variation of the dopant concentration. The similar trend is observed for the crystallite and particle size. The porosity and sintered density, however, vary in an opposite way with a variation of the dopant concentration. The same variation is found for the drift mobility and DC resistivity. The Arrhenius graphs of DC resistivity exhibit the semiconductor nature, for which the activation energy decreased with increasing the ...

  • Structural characterization and corrosion properties of electroless processed NiPMnO2 composite coatings on SAE 1015 steel for advanced applications.pdf.jpg
  • Article


  • Authors: Fayomi, O.S.I.; Akande, I.G.; Popoola, A.P.I.; Popoola, S.I.; Daramola, D. (2019)

  • In recent years, electroless NieP coatings with the incorporation of metallic oxides have received profound interest due to their unique properties and ability to enhance the operational performance of the base metal. These coatings have been utilised for numerous applications such as aerospace, automotive and industrial field where materials with exceptional qualities are required. This present work focuses on the improvement of the surface characteristics of mild steel via the electroless deposition of Nie- PeMnO2. The deposition was achieved by varying the mass concentration of MnO2 at fixed temperature and deposition time of 85 C and 20 min, respectively. The examinations of the ...

  • Statistical optimization of activated carbon from Thapsia transtagana stems and dyes removal efficiency using central composite design.pdf.jpg
  • Article


  • Authors: Machrouhi, A.; Alilou, H.; Farnane, M.; El Hamidi, S.; Sadiq, M.; Abdennouri, M.; Tounsadi, H.; Barka, N. (2019)

  • This study focused on the preparation of activated carbons from Thapsia transtagana stems by boric acid activation and their evaluation for dyes removal. Central composite design and response surface methodology were used to optimize the preparation conditions. The effect of activation temperature, impregnation ratio and activation time on iodine number (IN), methylene blue index (MB index) and removal efficiencies of methyl violet (MV), methyl orange (MO) and indigo carmine (IC) were fully evaluated. Activated carbon samples prepared in optimal conditions were characterized by FTIR, XRD, SEM-EDX, Boehm’s titration, and point of zero charge (pHPZC). The equilibrium data for dyes sor...

  • Spectroscopic, thermal, structural and electrical studies on VO2+ ions doped PVA_MAA_EA polymer blend films.pdf.jpg
  • Article


  • Authors: Pravakar, Ojha; Siddaiah, T.; Ramacharyulu, P.V.R.K.; Gopal, N.O.; Ramu, Ch.; Nagabhushana, H. (2019)

  • Pure and VO2þ ions doped PVA/MAA:EA polymer blend films were prepared by a solution casting method. XRD pattern reveals an increase in amorphicity with increase in doping. The dTGA study shows an enhancement of thermal stability of the system with increase in dopant concentration. The optical absorption spectrum exhibits three bands corresponding to the transitions 2B2g/2A1g, 2B2g/2B1g and 2B2g/2Eg, characteristic of VO2þ ions in octahedral symmetry with tetragonal distortion and reflects that the optical band gap decreases with the increase of mol% of VO2þ. EPR spectra of all the doped samples show a characteristic eightline hyperfine structure of VO2þ ions, which arises due to the i...

  • Simulation studies on the responses of ZnO-CuO_CNT nanocomposite based SAW sensor to various volatile organic chemicals.pdf.jpg
  • Article


  • Authors: Abraham, Nelsa; Krishnakumar, R. Reshma; Unni, C.; Philip, Daizy (2019)

  • Surface acoustic wave (SAW) sensors offer a sensitive platform for monitoring important physical entities with several advantages. They can operate well in extreme conditions such as high temperature, high pressure and toxic environment. This work presents a 2D model of SAW sensor with carbon nano tubes (CNT) as the adsorbent material. A second model was also created by incorporating ZnO and CuO nanospheres into the sensing layer. The responses of the two sensors towards various gases were analysed at room temperature. The design was modelled and analysed using COMSOL Multiphysics software which applies the finite element analysis to solve for Eigen frequencies. The shift in the reson...

  • Sensing properties of sulfonated multi-walled carbon nanotube and graphene nanocomposites with polyaniline.pdf.jpg
  • Article


  • Authors: Khan, Mahfoozurrahman; Anwer, Tarique; Mohammad, Faiz (2019)

  • Here, we discuss one of the simplest approaches for chemical functionalization of in-situ prepared polyaniline (Pani) and its nanocomposites with multi-walled carbon nanotubes (MWCNT) and graphene (GN) in chlorosulphonic acid. The effect of polymerization and functionalization was characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) analysis, Field emission scanning electron microscopy (FESEM) and electro-thermal analysis. Results also revealed the presence of p p interactions between Pani and carbon allotropes leading to the formation of charge-transfer complexes. This strong p p interaction significantly increased the resultant electrical conducti...

  • Role of graphene nanofluids on heat transfer enhancement in thermosyphon.pdf.jpg
  • Article


  • Authors: Das, Sidhartha; Giri, Asis; Samanta, Sutanu; Kanagaraj, S. (2019)

  • The thermophysical properties of graphene nanofluids in thermosyphon have been studied at different power inputs, temperatures and angles of inclination. The thermal conductivity of the graphene nanofluid is found to be 29% higher than that of the deionized water at 45 C. The viscosity of the graphene nanofluid increased with the concentration of graphene nanoparticles and decreased with increasing the temperature. It is observed that the wall temperature distribution of graphene nanofluid is found to be decreased in comparison to that of deionised water. The thermal resistance of thermosyphon is reduced with increasing the power input and irrespective of the inclination angle

  • Role of electronegativity on the bulk modulus, magnetic moment and band gap of Co2MnAl based Heusler alloys.pdf.jpg
  • Article


  • Authors: Kumar, Author-Shiv Om; Shukla, Vineeta; Srivastava, Sanjeev Kumar (2019)

  • In this paper, we have presented the comparative study of mechanical, electrical and magnetic properties of Co2MnAl1 xZx Heusler alloy with Z ¼ Si, Ge and Ga and x ¼ 0, 0.25, 0.75 and 1 using electronegativity (EN) model. We employed density functional theory for numerical calculations. It is found that Co2MnAl1 xZx with Z ¼ Ga, Ge follow the Vegard's law while Co2MnAl1 xSix does not follow the same trend. Among all composition Co2MnAl.25Si.75 alloy is found to be more compressible. Electronic density distribution depicts the ionic nature of Co2MnAl1 xZx alloy systems. The Co2MnAl1 xZx with Z ¼ Si, Ge possess larger magnetic moment and band gap with respect to Co2MnAl1 xGax system wh...

  • Role of Co dopants on the structural, optical and magnetic properties of lead-free ferroelectric Na0.5Bi0.5TiO3 materials.pdf.jpg
  • Article


  • Authors: Dung, D.D.; Doan, N.B.; Dung, N.Q.; Bac, L.H.; Linh, N.H.; Thanh, L.T.H.; Thiet, D.V.; Trung, N.N.; Khang, N.C.; Trung, T.V.; Duc, N.V. (2019)

  • Co-doped Na0.5Bi0.5TiO3 materials were fabricated by a sol-gel technique. The structural distortion of Codoped Na0.5Bi0.5TiO3 materials was due to the difference between the radii of Co dopants and Ti hosts. The optical band gap decreased from 3.11 to 1.83 eV because of the local state of the Co cation in the band structure. Room temperature ferromagnetism emerged as compensation of diamagnetic background and possibly intrinsic ferromagnetic signals. The magnetic moment was determined to be ~0.64 mB/Co at 5 K. The origin of the room temperature ferromagnetism in the Co-doped Na0.5Bi0.5TiO3 materials was also investigated through the first-principles calculation method. Our study provi...

Collection's Items (Sorted by Submit Date in Descending order): 1 to 20 of 251