Synthesis and Evaluation of CNT-Reinforced Silver-Matrix Nanocomposites
This work presents the synthesis and evaluation of multi-walled carbon nanotubes (MWCNTs) reinforced silver-matrix nanocomposite materials that were prepared by a chemical route commonly known as Electroless Coating / In-Situ reduction. The silver nitrate was used as a starting material and was reduced to silver over the surface of carbon nanotubes by the in-situ reduction process using hydrazine hydrate as the reducing agent. This resulted in the formation of silver particles attached with uniformly dispersed CNTs. The composite so formed was characterized by using techniques like FTIR, TEM, and XRD. In this investigation the emphasis is placed on the functionalization of CNTs and its role in deagglomeration in order to achieve uniform mixing of CNTs with the silver matrix. The effect of volume per cent of carbon nanotubes on properties like relative density, Vickers hardness and electrical conductivity of the Ag-CNT nanocomposite was investigated. The results showed that the addition of carbon nanotubes up to 9 % by volume to silver matrix results in an increase in the density and Vickers hardness whereas the electrical conductivity of the composite decreases with increasing volume fraction of CNT. Beyond 9 vol. % of CNT in Ag-CNT nanocomposite a sharp drop in the electrical conductivity is observed.
Sumedh A. Dayal, U.N.Puntambekar and P.B. Joshi