Showing papers by "Sampat Raj Vadera published in 2016"
TL;DR: In this article, an in situ co-precipitation reaction method has been reported for the preparation of CoFe2O4-RGO nanocomposites, where a hydrothermal technique was not used.
Abstract: Here, an ‘in situ’ co-precipitation reaction method has been reported for the preparation of CoFe2O4–RGO (CF–RGO) nanocomposites. To the best of our knowledge, this is the first time a simple synthetic method is reported for the preparation of CoFe2O4–RGO nanocomposites where a hydrothermal technique was not used. The novelty of this technique lies in its simplicity, cost-effectiveness, and the capability of large scale production of CoFe2O4–RGO nanocomposites. The synthesized CoFe2O4–RGO nanocomposites possess excellent microwave absorbing properties as well as high photocatalytic activity towards the degradation of various dyes under visible light irradiation. 85CF–15RGO (85 wt% CF and 15 wt% RGO) showed excellent microwave absorption properties with a Reflection Loss (RL) of −31.31 dB (∼99.94% absorption) at 9.05 GHz with an 8.2–10.92 GHz effective band width range. To the best of our knowledge 85CF–15RGO nanocomposite exhibited comparable and even superior microwave absorption properties in the X-band region than most of the ferrite based composites. 75CF–25RGO (75 wt% CF and 25 wt% RGO) acted as a very good magnetically separable photocatalyst for the degradation of various synthetic dyes (such as methyl orange, methylene blue, rhodamine B and a mixture of these dyes) under visible light irradiation emitted from a 100 W reading lamp. Moreover, CoFe2O4–RGO catalyst also showed easy magnetic separation with high reusability. The photocatalytic activity of 75CF–25RGO was found to be comparable and in some cases better than the various reported RGO–ferrite composites. The simple method of preparation and multifunctional character make CF–RGO nanocomposites attractive materials for application in the area of photocatalysis as well as microwave absorption.
56 citations
TL;DR: A Ni0.8Zn0.2Fe2O4 reduced graphene oxide nanocomposite has been synthesized by a simple co-precipitation technique as mentioned in this paper.
Abstract: A Ni0.8Zn0.2Fe2O4 reduced graphene oxide nanocomposite has been synthesized by a simple ‘in situ co-precipitation’ technique. This composite exhibited an ability to act as an excellent magnetically separable catalyst towards the degradation of various dyes as well as a toxic herbicide (trifluralin). It also demonstrated very good microwave absorption properties.
36 citations
TL;DR: In this paper, the authors show that BaTiO3/NBR composite systems exhibit dual-band microwave resonance at 9.5 and 16.5 GHz with −9 and −18 dB reflection losses, respectively.
Abstract: Tetragonal BaTiO3 bulk samples are prepared using the solid-state route in conjunction with intermediate high-temperature annealing steps. The (002) and (200) X-ray diffraction peaks near 2Ɵ~45° and 310, 520, and 720 cm−1 characteristic vibrational modes in Raman spectroscopic measurements confirm the tetragonal crystallographic structure of BaTIO3 bulk samples. The 1100°C annealed BaTiO3 sample showed optimal tetragonality ~1.016 and the same is used for BaTiO3–acrylonitrile butadiene rubber (NBR) composites at different BaTiO3 loading fractions in parts per hundred (PHR). These BaTiO3/NBR composite systems exhibit dual band microwave resonance, widening the operating window for microwave absorption applications. Eighty PHR BaTiO3/NBR composite exhibits microwave reflection losses (RL) at 9.5 and 16.5 GHz with ~−9 and ~−18 dB reflection losses, respectively. The onset of dual band is attributed to the ferroelectric-induced dipolar relaxation at 9.5 GHz and its second-order resonance at 16.5 GHz in such composite systems.
13 citations