Encapsulation of CuO nanoparticles inside the channels of the multi-walled carbon nanotubes functionalized with thermal stress

Commercially available multi-walled carbon nanotubes (MWCNTs), which are generally naturally intertwined, were cut by sudden, repeated exposure to oxidizing conditions in the air. This process has been proved to be an effective handle of producing open ended and medium level functionalization. Results showed that the typical closed graphite end caps for carbon nanotubes via functionalized with thermal stress (CNT-M) can be shorten long MWCNTs, while improving average graphite quality. These results were supported by the increase of Brunauer-Emmett-Teller (BET) surface area from 284.772 m(2)g(-1) to 463.890 m(2)g(-1). Copper oxide nanoparticles (CuO-PEGx) which were synthesized using polyethylene glycol (PEG) nonionic surfactants with different derivative (polyethylene glycol methyl ether methacrylate) and molecular weights (Mw: 200, 2000 and 5000), were encapsulated into CNT-Ms by simple wet impregnation technique. The filling capacity depended on the preparation conditions and particle size of CuO nanostructures. While other samples showed a multiple particle size distribution, only CNT-M-CuO-PEG950 sample indicated uniform particle size distribution with the smallest particles (3.6 nm) inside CNT-M channels. The BET surface areas of the nanocomposites (274.865-304.859 m(2)g(-1)) were lower than the surface area (463.890 m(2)g(-1)) of CNT-Ms while they were close and large to the surface area of MWCNTs (284.772 m(2)g(-1)).