@office.cnn@jmi.ac.in
Centre for nanoscience and nanotechnology
A K Hafiz
Materials Science, Physics and Astronomy, Electronic, Optical and Magnetic Materials
Scopus Publications
Scholar Citations
Scholar h-index
Scholar i10-index
Santosh Chackrabarti, R. A. Zargar, Tuiba Mearaj, Yassar Arfat, A. K. Hafiz, and Muzaffar Iqbal Khan
Springer Science and Business Media LLC
R. A. Zargar, Santosh Chackrabarti, Tuiba Mearaj, I. M. Ashraf, and A. K. Hafiz
The Electrochemical Society
A thick TiO2-CuO composite film is deposited on a Si substrate by a low-cost screen printing method. Both anatase and CuO-doped TiO2 are characterized for diode applications. X-ray Diffraction (XRD) confirms that the composite film exists as an anatase phase of TiO2 and a monoclinic phase of CuO with a maximum diffraction of (101) plane. SEM images depict the less severe agglomeration of particles for the doped TiO2 as compared to the anatase TiO2. The UV–visible spectra reveal a direct band gap shift of 3.35 eV (pure TiO2) to 3.26 eV (doped TiO2). From the PL study, the blue shaded emission is perfectly derived for anatase TiO2 while the color is seen to change to the white zone supporting TiO2-CuO composite formation as depicted by the CIE diagram. The diode parameters such as ideality factor (n) and barrier height (Φb) are calculated with the help of I–V characteristics. This only reported novel effort on screen-printed TiO2-CuO thick film may help in manufacturing possible LEDs for optoelectronic applications.
Tuiba Mearaj, Shobha Shukla, A. K. Hafiz, Manika Khanuja, R. A. Zargar, and Santosh Chackrabarti
Springer Nature Singapore
R.A. Zargar, S. Chackrabarti, M.H. Malik, and A.K. Hafiz
Elsevier BV
S. Chackrabarti, R.A. Zargar, S. Joseph, M. Arora, A. Aziz, and A.K. Hafiz
Elsevier BV
Santosh Chackrabarti, Rayees A. Zargar, Jyoti Bansal, Tho-alfiqar A. Zaker, and A.K. Hafiz
Elsevier BV
R. A. Zargar, M. Arora, S. Chackrabarti, S. Ahmad, J. Kumar, and A. K. Hafiz
World Scientific Pub Co Pte Lt
Cadmium-doped zinc oxide nanoparticles were derived by simple chemical co-precipitation route using zinc acetate dihydrate and cadmium acetate dihydrate as precursor materials. The thick films were casted from chemical co-precipitation route prepared nanoparticles by economic facile screen printing method. The structural, morphological, optical and electrical properties of the film were characterized relevant to alcohol vapor sensing application by powder XRD, SEM, UV-VIS and DC conductivity techniques. The response and sensitivity of alcohol (ethanol) vapor sensor are obtained from the recovery curves at optimum working temperature range from 20[Formula: see text]C to 50[Formula: see text]C. The result shows that maximum sensitivity of the sensor is observed at 25[Formula: see text]C operating temperature. On varying alcohol vapor concentration, minor variation in resistance has been observed. The sensing mechanism of sensor has been described in terms of physical adsorption and chemical absorption of alcohol vapors on cadmium-doped zinc oxide film surface and inside film lattice network through weak hydrogen bonding, respectively.
Santosh Chackrabarti, Dhrub Sharma, and Ram Kafle
Elsevier BV
S. Chackrabarti, R. A. Zargar, A. Aziz, and A. K. Hafiz
Springer Science and Business Media LLC
Santosh Chackrabarti, Dhrub Sharma, Shereena Joseph, Tho-alfiqar A. Zaker, A.K. Hafiz, and Ram Kafle
Canadian Science Publishing
We report on the temperature-dependent spectral shifts in low power 670 nm AlGaInP multiple quantum well red laser diodes due to band gap narrowing at room temperatures (5–45 °C). The spectral shift mechanism is explored with a threshold current density of 11.41 kA/cm2 and a good characteristic temperature of 114 K. The photoluminescence peak intensity shifts towards higher wavelengths and the full width at half maximum increases with increase in temperature from 5 to 45 °C. We use a Hamiltonian system considering the effective mass approximation to formulate the carrier concentrations. The band gap narrowing value determined by a simple formula amounts to 59.15 meV and displays N1/3 dependence at higher densities. The carrier density dependence conveys that the redshift of the spectral emission is due to band gap narrowing.
S. Chackrabarti, R.A. Zargar, D. Ali, M. Arora, A. Aziz, and A.K. Hafiz
Elsevier BV
Rayees Ahmad Zargar, Santosh Chackrabarti, Md. Shahabuddin, Jitendra Kumar, Manju Arora, and Aurangzeb Khurram Hafiz
Springer Science and Business Media LLC
Rayees A. Zargar, Santosh Chackrabarti, Shereena Joseph, Mohd. Shahid Khan, Rizwan Husain, and A.K. Hafiz
Elsevier BV