Multi-Walled Carbon Nanotubes Chemically Modified by Cobalt Tetraaminophthalocyanines with Excellent Electrocatalytic Activity to Li/SOCl₂Battery

Abstract

Fluorinated Multi-walled carbon nanotubes (F-MWCNTs) are chemically modified successfully by cobalt 2, 9, 16, 23-tetraaminophthalocyanine and cobalt 1, 8, 15, 22-tetraaminophthalocyanine respectively. Their structures are characterized by IR, SEM, XPS and XRD. Important in this context is that the covalent linkages between F-MWCNTs and cobalt phthalocyanines are corroborated by monitoring the diagnostic signature of the nitrogen atoms as part of the formed -NH- bonds in them by XPS. The electrocatalytic activity of the two kinds of modified F-MWCNTs to Li/SOCl2 battery is evaluated by adding them into the electrolyte of the battery. It is found that the modified F-MWCNTs can dramatically improve the discharge voltage and lengthen the discharge time of the battery, and finally make the capacity of the battery increase by 97.5% and 103.3% than that of the battery in the absence of them. The excellent electrocatalytic performance of the modified F-MWCNTs may be owing to the fine synergistic effect between the cobalt phthalocyanines and the MWCNTs in them. A reasonable catalytic mechanism of the modified F-MWCNTs to the battery is proposed according to the CV results.