scholarly journals Spectroscopic Evaluation of Optical Parameters of a Transition Metal Salt Filled Polymer Material

2018 ◽  
Vol 68 (2) ◽  
pp. 225 ◽  
Author(s):  
M. Banerjee ◽  
Amit Jain ◽  
G. S. Mukherjee

Transition metal salt, manganese chloride was incorporated into polyvinyl alcohol (PVA) to prepare metal salt filled polymer material (M-PVA) and their optical properties were evaluated. XRD, UV-vis, and FTIR analyses reveal that there is strong interaction between PVA and the manganese chloride salt. From XRD analysis, the inter-chain separation in pristine PVA and M-PVA was found to be 5.62 Ǻ and 4.70 Ǻ, respectively; thus indicating that the packing of polymer chains is more compact under the influence of manganese chloride. Optical band gap of PVA was found as 5.06 eV but such band gap was reduced on incorporation of manganese chloride into the PVA matrix system with corresponding increase in optical conductivity. Spectral evaluation indicates that refractive index of M-PVA decreases faster than that of PVA in the visible range. Abbe Number was found to have decreased on incorporation of manganese chloride into the PVA matrix system indicating increase in optical dispersion in conformity with the trend of increase in dispersion energy (Ed). The average interband oscillator wavelength was found close to the respective values of absorption edges.

Polymers ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1316
Author(s):  
Shujahadeen B. Aziz ◽  
Muaffaq M. Nofal ◽  
Hewa O. Ghareeb ◽  
Elham M. A. Dannoun ◽  
Sarkawt A. Hussen ◽  
...  

The influence of dispersing Al-metal complex on the optical properties of PVA was investigated using UV–visible spectroscopy. Polymer composite films with various Al3+-complex amounts in the PVA matrix were arranged by solution casting technique by means of distilled water as a widespread solvent. The formation of Al3+-metal complex was verified through Ultraviolet–visible (UV-Vis) and Fourier-transform infrared spectroscopy (FTIR) examinations. The addition of Al-complex into the polymer matrix led to the recovery of the optical parameters such as dielectric constant (εr and εi) and refractive index (n). The variations of real and imaginary parts of complex dielectric constant as a function of photon wavelength were studied to calculate localized charge density values (N/m*), high-frequency dielectric constant, relaxation time, optical mobility, optical resistivity, and plasma angular frequency (ωp) of electrons. In proportion with Al3+-complex content, the N/m* values were amplified from 3.68 × 1055 kg−1 m−3 to 109 × 1055 kg−1 m−3. The study of optical parameters may find applications within optical instrument manufacturing. The optical band gap was determined from Tauc’s equation, and the type of electronic transition was specified. A remarkable drop in the optical band gap was observed. The dispersion of static refractive index (no) of the prepared composites was analyzed using the theoretical Wemple–DiDomenico single oscillator model. The average oscillator energy (Eo) and oscillator dispersion energy (Ed) parameters were estimated.


Catalysts ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 900
Author(s):  
Hao Lu ◽  
Fengrui Jia ◽  
Chuang Guo ◽  
Haodan Pan ◽  
Xu Long ◽  
...  

The effect of shale ash (SA)-based catalysts (SA as carriers to support several transition metal salts, such as ZnCl2, NiCl2·6H2O, and CuCl2·2H2O) on oil shale (OS) pyrolysis was studied. Results showed that SA promoted OS pyrolysis, and the optimum weight ratio of OS:SA was found to be 2:1. The SA-supported transition metal salt catalyst promoted the OS pyrolysis, and the catalytic effect increased with increasing load of the transition metal salt within 0.1–3.0 wt%. The transition metal salts loaded on the SA not only promoted OS pyrolysis and reduced the activation energy required but also changed the yield of pyrolysis products (reduced shale oil and semi-coke yields and increased gas and loss yield). SA-supported 3 wt% CuCl2·2H2O catalyst not only exhibited the highest ability to reduce the activation energy in OS pyrolysis (32.84 kJ/mol) but also improved the gas and loss yield, which was 4.4% higher than the uncatalyzed reaction. The supporting transition metal salts on the SA also increased the content of short-chain hydrocarbons in aliphatic hydrocarbons in shale oil and catalyzed the aromatization of aliphatic hydrocarbons to form aromatic hydrocarbons. The catalytic activity of the transition metal salt on the SA-based catalyst for OS pyrolysis decreased in the order of CuCl2·2H2O > NiCl2·6H2O > ZnCl2.


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