Sol-Gel Synthesis, Magnetic and Optical Properties of Co2+:Nd3+::2:1 molar ratio doped in SiO2
Journal Title: JOURNAL OF ADVANCES IN CHEMISTRY - Year 2015, Vol 11, Issue 3
Abstract
Synthesis of Co2+:Nd3+::2:1 molar ratio doped SiO2 with Co2+ ions concentrations viz. 0.0004, 0.001, 0.002, 0.003, 0.004 moles in S1-S5, respectively are performed by sol-gel method. Observed values of the densities and the concentrations of the Co2+ ions in S1-S5 are found to be 2.26, 2.29, 2.37, 3.44, 2.49 g/cm3, and ~ 1020 ions/g, respectively. Powder XRD results show the formation of amorphous SiO2 phase in the samples. DTA-TGA/DTG traces in the range 27-700 ˚C show no characteristic event in the samples. The IR peak in the range 412-418 cm-1 is ascribed to the asymmetric mode of the octahedral [NdO6/2]3- units. The peak around 440 cm-1 in S1-S5 is due to the ν2-symmetric bending mode of the tetrahedral [SiO4/2]4- units. The weak IR peak ~ 670 cm-1 is due to the ν1-mode of the tetrahedral [CoO4/2]4- units. The calculated values of the magnetic susceptibility from the observed magnetic moments data at 300 K are found to be ~10-6  emu/gG in S1-S5 which show the weak paramagnetic nature of the materials.  The EMR lineshapes recorded at 6, 50, 77, and 300 K are very broad, isotropic and smeared out with only two detectable characteristic peaks. The giso-value ~ 2.3 is due to the doped Co2+(3d7) ions in tetrahedral coordinations, while the giso-value ~ 2.01 is due to the doped Nd3+(4f3) ions in distorted octahedral coordinations. The lineshapes only at 6 K are distinct, while at higher temperatures  these peaks are severely smeared out. The optical absorption broad band at ~750 nm (13262 cm-1) is assigned to 4I9/2 ® 4F7/2 + 4S3/2 transitions in optically active Nd3+(4f3) ions, and the peak ~ 520 nm (19230 cm-1) is attributed to 4A2g ® 4T1g(P) transitions in Co2+ (S=3/2, 3d7) ions in tetrahedral coordinations.
Authors and Affiliations
Bidhu Bhusan Das, Ruppa Govinda Rao
Keywords
Related Articles
- EP ID EP652832
- DOI 10.24297/jac.v11i3.864
- Views 112
- Downloads 0
Performance of BFRP and GFRP Hollow Circular Steel columns subjected to axial compression loads
Recent research has been focused on rehabilitation and strengthening of deteriorated steel structures and bridges using Fiber Reinforced Polymer (FRP) materials. This paper deals with the behavior of FRP confinement of h...
IMPACT OF PRESSURE ON THE PERFORMANCE OF PROTON EXCHANGE MEMBRANE FUEL CELL
The Proton Exchange Membrane (PEM) fuel cell performance not only depends on temperature but also depends on the operating pressure, which will increase the performance of the PEM fuel cell. The PEM fuel cell with serpen...
MAINTENANCE STRATEGY EVALUATION BASED ON AHP – TOPSIS
This paper presents an application of Analytical Hierarchy Process (AHP) is combined with Technique for Order Preference by Similarly to Ideal Solution (TOPSIS) model for selection of the best maintenance strategy for pu...
SYNTHESIS AND REACTIONS OF SOME NEW MORPHOLINYLPYRROLYL TETRAHYDROTHIENO[2,3-c] ISOQUINOLINE
Hydrazinolysis of ethyl-5-morpholin-4-yl-1-(1H-pyrrol-1-yl)-6,7,8,9-tetrahydrothieno[2,3-c]iso- quinoline-2-carboxylate afforded the corresponding carbo- hydrazide which upon condensation with aromatic aldehy...
EXPERIMENTAL INVESTIGATION OF MECHANICAL PROPERTIES OF UNTREATED NEW AGAVE ANGUSTIFOLIA MARGINATA FIBER REINFORCED EPOXY POLYMER MATRIX BIO-COMPOSITE MATERIAL
In recent years, the natural fibers playing a vital role in worldwide. The main purpose of using natural fiber is biodegradable, cost wise low, easily available and at the same time strength to weight ratio is high. In t...