Amrish K. Panwar

Effect of evaporation on the contact angle of a sessile drop on solid substrates

The effect of evaporation on the contact angle of a sessile drop of water on glass and polycarbonate substrates has been investigated. It has been observed that the contact radius depends on the initial mass of the drop and remains constant throughout the progress of evaporation. The evaporation rates in both systems are proportional to the contact radii of sessile drops. The contact angle, however, decreases as evaporation proceeds. In the case of water-glass system, the contact angle decreases almost linearly with time. On the other hand, in water-polycarbonate system, the contact angle shows a considerable departure from linearity. It has been shown that the non-linear behavior of contact angle becomes more pronounced with increasing initial contact angle.

Investigation of A- and B-site Fe substituted BaTiO3 ceramics

In this work, we report the synthesis and investigations of Ba1−xFexTiO3 (BFeT) and BaTi1−x FexO3 (BTFe) ceramics by solid state reaction method. BFeT show relaxor behaviour in the studied frequency range i.e., 10 kHz to 100 kHz with high dielectric constant in a wide temperature range of 75 °C. BTFe shows frequency dispersion at 10 kHz and almost flat dielectric response at 100 kHz and lower dielectric constant value compared to BFeT. Polarization–electric field loops of both BFeT and BTFe shows suppressed ferroelectric behaviour as compared to pristine BaTiO3(BT). Magnetization–magnetic field loops show ferromagnetic behaviour in both BFeT and BTFe at room temperature.

Facile Synthesis of Semiconducting Ultrathin Layer of Molybdenum Disulfide

In this paper, we have reported a simple and efficient method for the synthesis of uniform, highly conducting single or few layer molybdenum disulfide (MoS2) on large scale. Scanning Electron Microscopy (SEM) and High Resolution Transmission Electron Microscopy (HRTEM) have been used for the confirmation of mono or few layered nature of the as-synthesized MoS2 sheets. X-ray Photoelectron Spectroscopy (XPS), X-Ray Diffraction (XRD) and Raman Spectroscopy have also been used to study the elemental, phase, and molecular composition of the sample. Optical properties of as-synthesized sample have been probed by measuring absorption and photoluminescence spectra which also compliment the formation of mono and few layers MoS2 Current-voltage (I-V ) characteristics of as-synthesized sample in the pellet form reveal that MoS2 sheets have an ohmic character and found to be highly conducting. Besides characterizing the as-synthesized sample, we have also proposed the mechanism and factors which play a decisive role in formation of high quality MoS2 sheets.

Synthesis and electrochemical properties of low-temperature synthesized Li2MnO3/MWCNT/super P as a high capacity cathode material for lithium ion batteries

The present work describes the synthesis and electrochemical properties of layered-Li2MnO3 with different carbon additives usingball millingroute. X-ray diffraction (XRD) pattern reveals that all the prepared samplesbelong tom-Li2MnO3 phasehavingC2/m space group. LMOA (Li2MnO3sample with MWCNT’s)providesmaximum discharge capacity among all the prepared samples. The LMOAcathodeoffers acapacity of 121±5 mAhg-1 at a current density of 10 mA/g for the initial cycle in the voltage windowof 2.0-4.8 V.The present work describes the synthesis and electrochemical properties of layered-Li2MnO3 with different carbon additives usingball millingroute. X-ray diffraction (XRD) pattern reveals that all the prepared samplesbelong tom-Li2MnO3 phasehavingC2/m space group. LMOA (Li2MnO3sample with MWCNT’s)providesmaximum discharge capacity among all the prepared samples. The LMOAcathodeoffers acapacity of 121±5 mAhg-1 at a current density of 10 mA/g for the initial cycle in the voltage windowof 2.0-4.8 V.