J.Y. Patil

Enhanced acetone sensing performance of nanostructured Sm2O3 doped SnO2 thick films

Abstract In the present work, we synthesized Sm 2 O 3 doped SnO 2 in order to prepare a selective acetone sensor with fast response, quick recovery and good repeatability. Pure as well as 2 mol.%, 4 mol.%, 6 mol.% and 8 mol.% Sm 2 O 3 doped SnO 2 nanostructured samples were synthesized by using a co-precipitation method. The characterization of the samples was done by thermogravimetric and differential thermo-gravimetric analysis (TG-DTA), X-ray diffraction (XRD), field emission gun-scanning electron microscopy (FEG-SEM), energy dispersive analysis by X-rays (EDAX), high resolution scanning electron microscopy (HR-TEM), selected area X-ray diffraction (SAED), Brunauer-Emmet-Teller (BET) and ultraviolet-visible-near infrared (UV-Vis-NIR) spectroscopy techniques. The gas response studies of liquid petroleum gas, ammonia, ethanol and acetone vapor were carried out. The results showed that Sm doping systematically lowered operating temperature and enhanced the gas response and selectivity for acetone. The response and recovery time for 6 mol.% Sm 2 O 3 doped SnO 2 thick film at the operating temperature of 250 °C were 15 and 24 s, respectively.

Structural and Bulk Magnetic Properties of Ni‐Co‐Zn Ferrites

Ni0.35−xCoxZn0.65fe2O4 (x = 0.00, 0.01, ‐‐‐‐0.10) ferrites were synthesized by coprecepitation technique, using oxalate precursors. The x‐ray diffraction studies have revealed a single spinel phase for all the compositions. Lattice parameter [a] increases with increasing Co2+ content. The magnitude of grain size (D) observed to be the same as reported by PJ. van der Zaag et al [1] for mono‐domains. The decrease in initial permeability is attributed to decrease in (i) grain size (D), (ii) decrease in saturation magnetization (Ms), and (iii) increase in magnetocrystalline anisotropy (K1). The variation in magnetocrystalline anisotropy is significant and becomes positive and large with the content of Co2+.