Figure 3.

Typical SEM micrographs and HRTEM micrograph of CuO, MWNT, and Cu. (a) Typical SEM micrograph of CuO nanoparticles; (b) typical SEM micrograph of MWNTs; (c) typical HRTEM micrograph of MWNTs; (d) typical SEM micrographs of Cu nanoparticles.