International Journal of Innovative Research in Physics (IJIIP)
(ISSN Number(Online) - 2687-7902)
(ISSN Number(Print) - 2689-484X)

Volume1 Issue3:

Spectroscopic characterization and photo catalytic degradation ability of ternary oxides of Cobalt

Moushumi Dutta Purkayastha1*,Partha Pratim Ray2,Tapas Pal Majumder1,Mitali Sarkar3

1Department of Physics, University of Kalyani-741235, West Bengal, India
2Department of Physics, Jadavpur University, Kolkata-700032, West Bengal, India
3Department of Chemistry, University of Kalyani, Kalyani-741235, West Bengal, India
Page Number: 1-16

In the present work we have prepared and characterized the two ternary forms of cobalt titanate namely ilmenite and cubic by the sol-gel technique simply by replacing the titanium precursor and using a cationic surfactant micelle solution followed by calcinations at 600°C and 800°C respectively. In both cases, the nanopowders revealed a dark bluish green color, different morphologies of spherical, rhombus and needle shapes with mean particle sizes 29 and 37 nm, respectively. Bearing growing environmental concerns in mind, we have also highlighted a simple nano chemistry based clean and efficient process for effective degradation of hazardous malachite green oxalate dye by an in-situ ultraviolet irradiation set-up. In this field there is hardly any report involving comparative study of ternary oxides of cobalt as potential candidates for photo catalytic degradation. We ultimately observed that cobalt meta titanate proved itself the optimal catalyst at a calcination temperature of 600°C showing a maximum degradation efficiency of 96.38% It also showed a better first-order rate constant of 0.01636 min -1 . A decent attempt to correlate photoluminescence and photo catalysis has also been made. Also, a heterojunction has been fabricated with cobalt meta titanate and the parameters of crucial importance in photocatalysis namely conductivity, carrier mobility, transit time evaluated from the current-voltage characteristics.
Keywords: Nanoparticles; CTAB micelle solution; Photocatalytic degradation; Reaction kinetics, Heterojunction


Estimation of trap energy of fuchsin dye sensitized Organic Photovoltaic Device based on Titanium Dioxide (TiO 2 )

Dipankar Sahoo1*,N. B. Manik2

1Department of Physics, Condensed Matter Physics Laboratory, Jadavpur University, Kolkata- 700 032
Page Number: 17-23

Recently, dye sensitized photovoltaic cell plays an important role as a renewable source of energy because of low material cost, easy processing techniques. But the organic devices are prone to traps due to which charge carriers get trapped or recombined within the device before collection at the electrodes. So traps limit the device performance. The study on the charge transport mechanism enables us to estimate this trap energy. In this work, we have designed the photovoltaic device and estimated the trap energy of inexpensive water-soluble Fuchsin dye based photovoltaic cells. To design a photovoltaic device we have used ITO as a front electrode and copper as a back electrode. 540mg of TiO 2 nanoparticles and 100mg of Fuchsin dye mixed well in N, N-Dimethyl formamide (DMF). A thin layer of this TiO 2 nanoparticles and dye has been deposited between two electrode using popular method named doctor’s blade method. A drop of electrolyte made of lithium percolate (LiClO 4 ), ethylene carbonate (EC) and propylene carbonate (PC) solution has been used to obtain better device performance. The analysis of dark current density- voltage (J-V) characteristics using exponential charge transport mechanism of this photovoltaic cell the trap energy has been calculated 0.5399 ± 0.006 eV. Also, we have observed photovoltaic effect of this device. Under illumination of 120 kLUX intensity, maximum short circuited current density is obtained 4.62 μA/cm 2 and open circuited voltage is 0.24 Volt.
Keywords: Fuchsin dye, trap energy, short-circuited current density, open-circuited voltage.


Molecular dynamics simulations to see the effect of temperature and pressure change on the dynamics of protein

Osheen Yadav1, Sunita Negi2*

1Department of Applied Physics, Amity School of Applied Sciences, Amity University, Haryana-122413, INDIA
2School of Basic & Applied Sciences, G. D. Goenka University, Gurugram, Haryana-122103, INDIA
Page Number: 24-29

In this work we study the effect of temperature and pressure on the dynamics of calmodulin protein using molecular dynamics simulations. The calmodulin protein is used for this study as a first step which can be extended further to other proteins. Calmodulin is a calcium binding protein and thus plays a very important role in the transport of calcium ions inside the cell. The temperature is earlier reported to play an important role in the dynamics of this protein which is applicable to the other proteins as well. In this study we therefore study the combined effect of temperature and pressure on the conformation change of this protein. The pressure alone is not observed to play a significant role in the dynamics of the protein whereas pressure along with temperature is observed to change the conformation of the protein to a large extent. The results were confirmed with the molecular dynamics simulations performed with the help of NAMD software. These results are consistent with the experimental results of the other workers performed with fourier transform infrared spectroscopy. Temperature is observed to pave pathways to expand/unfold the whole protein structure making it more susceptible to the effects of pressure.
Keywords: Protein, Conformation, Calmodulin, Molecular Dynamics


Long-range Graphene Surface Plasmon Polariton induced Tunable Optical Bistability in Terahertz Range

Aparupa Kar1 , Nabamita Goswami2* , Ardhendu Saha 2*

1Department of Electronics and Instrumentation Engineering, National Institute of Technology Agartala, Barjala, Jirania, Tripura (West), Pin:-799046, India.
2Department of Electrical Engineering, National Institute of Technology Agartala, Barjala, Jirania, Tripura (West), Pin:-799046, India.
Page Number: 30-36
An idea towards the low threshold optical bistability and tunability of bistable thresholds at THz frequency under realistic situation is analyzed through a proposed multilayered configuration. The proposed configuration comprises a coupling prism of silicon, and monolayer graphene sheets spatially separated through 35 nm thick polymer which is sandwiched between an air gap of thickness 4.6 μm and a kerr polymer (GaAs) at 300 K temperature and at an incident light frequency of 2 THz. Utilizing the large nonlinear effect of the configuration obtained by the nonlinearity of the kerr polymer and the high local field effect due to long-range graphene surface plasmon resonance, the switching-down and switching-up threshold values for optical bistability have been markedly reduced upto 1.21×10 5 V/m and 1.24×10 5 V/m respectively thereby rendering a minimum threshold intensity of 7.2 kW/cm 2 than the articles reported till date. Tunability of the switching-down and switching-up threshold values have also been realized from 1.21×10 5 V/m to 5.18×10 5 V/m and 1.24×10 5 V/m to 1.424×10 6 V/m respectively through electrical or chemical modification of the charge carrier density and hence fermi energy of the graphene from 0.23 eV to 0.41 eV and from 1.21×10 5 V/m to 1.56×10 5 V/m and 1.24×10 5 V/m to 2.12×10 5 V/m respectively for the variation in incident angle from 70° to 88°. The effect of damping rate of graphene on optical bistability behavior has also been observed. Therefore the proposed optical bistable configuration finds potential applications in the field of all-optical switching, optical transistor, optical logic, nano-illumination and optical memory with low input threshold at THz frequency and can also be used to realize tunable optical bistable device for future THz optical communication technology.
Keywords: Optical Bistability, Plasmonics, Graphene Plasmons, Electromagnetic optics


A Novel Alumina-Magnesium oxide- Reduced Graphene Composite: Synthesis and Characterizations

Binod Bihari Palei * , Tapan Dash, Susanta Kumar Biswal. R.Saktivel

1Centurion University of Technology and Management, Odisha, India CSIR-IMMT, Bhubaneswar-India

Page Number: 37-47

A novel new alumina-magnesium oxide with reinforced of reduced graphene oxide (RGO) composite materials have been synthesized by using a horizontal high energy planetary ball milling process. The composite has very high density, improved mechanical properties, retaining strength under higher temperatures, and high thermal conductivity. Al 2 O 3 -MgO-RGO composites can be used as a novel material for many industrial applications. The effect of RGO in the combination of Al 2 O 3 and MgO have a potential scope in several demanding fields, including automobile, aerospace, defenses, sports, electronics, bio-medical, and other industrial purposes. The prepared composites have been studied by X- ray diffraction (XRD), Field emission scanning electron microscopy (FESEM), micro Raman spectroscopy, Transmission electron microscope, Automatic density meter, Particle size analyzer.
Keywords::Reduced Graphene Oxide, Composite, Microstructural property


Antiferromagnetism in two-orbital model for s superconductors s± -wave iron based

P. K. Parida1,3,B. Pradhan2,S. Sahoo3

1Department of Physics, Dhenkanal (A) College, Dhenkanal-759001, Odisha, India
2Department of Physics, B.J.B. College, Bhubaneswar-751014, Odisha, India
3Department of Physics, NIT, Durgapur-713209, West Bengal, India
Page Number: 48-56

In iron based superconductors the superconducting phase occurs near the onset of antiferromagnetism order. Unconventional superconductivity has led to extensive experimental and theoretical studies on the effect of electron correlations and on the nature of magnetism in iron based superconductors. For the study of antiferromagnetism in these superconductors we have proposed a tight-binding two-orbital model Hamiltonian. We have proposed here a s ± -wave pairing symmetry of the form cosk x X cosky in the model in mean-field approximation. The model is solved by Zubarev’s double-time Green’s function technique to find the self-consistent gap equation and is solved self-consistently numerically. The antiferromagnet- ism gap, specific heat, conduction electron density of states and energy band structure for the system are calculated.
Keywords: Iron based superconductors, Antiferromagnetism, Density of states


Application of MEG in Increasing External Quantum Efficiency Over 100%

Shubham Kumar1 , Kaustav Saha2

1Department of Information Technology, Institute of Engineering and Management, Saltlake, Kolkata-700075
2Department of Computer Science Engineering, Institute of Engineering and Management, Saltlake, Kolkata-700075
Page Number: 57-59

This review paper focuses on increasing the efficiency of Solar cell using Quantum Dot. The principle idea is using MEG (Multiple exciton Generation). MEG is more efficient in quantum confined nanostructures than in bulk semiconductors because the momentum preservation prerequisite is relaxed. Even the carrier-carrier interactions are huge due to strong confinement. The carrier multiplication decoupling from the effective band gap allows amplified photo-voltage for corresponding carrier multiplication. Along with this, it was also found that external quantum efficiency (EQE) would reach almost 100%, sometimes even exceeding it, for energy which is greater than twice the band gap energy. This is due to the fact that high energy photons have the ability to produce more than one photo carrier pair. MEG is definitely a promising route to increasing solar cell efficiency. If a threshold of twice the band gap energy could be realized for impact ionization in a colloid Quantum Dot cell, the theoretical maximum possible conversion efficiency would shift to above 60%. The goal is to capture maximum energy incident on a given plane and targeting high- yield transportation of the resultant photo generated charge.


Wireless 5g: One More Revolutionary Step Towards Glorifying Internet

Shafaqnigar1, Amir Kha2,Md Nasir3

1Department of Basic Sciences and Humanities, Institute of Engieneering & Management Salt Lake, Kolkata-700075

Page Number: 60-64

5-G stands for 5th generation. An upcoming technology in India which promises high speed and consistent internet. It might be available in India in 2019.Rapid increase in use of internet has put many demands which are beyond the reach of 4g like improved data rate, decreased latency, less power consumption and better quality of service. To meet these measures a revolutionary step must be taken in the form of 5g.Our paper presents a comparative based study on 5g applications. 5g is expected to revolutionize the internet much more than Jio's 4g did. Users will experience high valued fast and powerful technology like never before. 5g technology will have extraordinary data capabilities and will have ability to tie together unrestricted call volumes and infinite data broadcast within latest mobile operating system. 5g technology will take over world market easily in coming days. 5g technology will have an extraordinary capacity to support soft wares and consultancy. It will have endless benefits. It will help in visualization of universe, galaxies, planets and extra celestial bodies. It will take all delivery service out of business prospect.5g technology will be providing large broadcasting of data in gigabit. It will enhance many medical procedures. Now we all know there's always another face of any coin.5g technology will have some disadvantages too. Since 5g services are likely to run on ultra-high spectrum bands which travels shorter distance compared with lower bands, they will be more suited to enhance indoor coverage.5g technology will have higher frequency waves which could be blocked by buildings and might lose intensity over distance so it will be a tough challenge and will require large investments. In conclusion, despite of some problems, 5g technology will be an innovation for mobile industry and will definitely change people's life.