Authors: S Sathyamoorthi KR Saravanan D Velayutham V Suryanarayanan
Publish Date: 2012/06/08
Volume: 42, Issue: 8, Pages: 595-606
Abstract
Multisweep cyclic voltammetric CV responses of nickel copper Monel and nickel–copper alloy had been extensively studied and compared in different nonaqueous solvents such as acetonitrile AN propylene carbonate PC and sulpholanecontaining anhydrous hydrogen fluoride AHF medium in the absence and the presence of triethylamine Et3N The quantity of dissolution and surface morphological transformation on the electrodes as a result of anodic polarisation were investigated by means of atomic absorption spectroscopy and scanning electron microscopy SEM respectively The CV study indicates that Ni Cu and their alloys are highly unstable in AN/AHF medium Surface morphology of Ni after polarisation in this medium reveals the generation of number of pits whereas the evolution of small crystallites of CuF2 is noted on the polarised alloy material as evidenced by SEM pictures The dissolution characteristics decrease significantly in PC/AHF medium and become low in sulpholanecontaining fluoride medium on the four electrodes The relative solubility of metal fluoride film in the three solvents increases in the order sulpholane PC AN The voltammograms suggest that addition of Et3N 05 M to AN and PCcontaining AHF medium helps both in maintaining uniform dissolution and generating compact fluoride film on the electrode surface The addition of Et3N to AHF/sulpholane medium shows only little influence in improving the electrocatalytic oxidation processThe authors thank Director CSIRCECRI Karaikudi for his keen encouragement in publishing this work Financial support from DRDO New Delhi is greatly acknowledged Thanks are due to Dr RP Singh and Dr Raju Brahma CFEES DRDO New Delhi for their fruitful discussions
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