Template Synthesis of Cobalt Nanowires Using PS-b-PMMA Block Copolymer

Cobalt nanowires with $18 {\pm} 5$ nm diameter were grown in the self-assembled diblock copolymer templates using electrodeposition technique. The diblock copolymer templates with hexagonally ordered nanoporous structure were successfully synthesized by varying the copolymer thickness from 50 nm to 430 nm and post annealing at temperature 180$^{\circ}$ C for 24 h. The minimum optimized pore sizes of the template were $18 {\pm} 5$ nm with well order hexagonal nanoporous structure at copolymer thickness from 350 nm to 430 nm. Cobalt nanowires were then successfully deposited using three electrode configuration potentiostatic electrodeposition methods. To remove the cross linked polystyrene of the template and to display the cobalt nanowires, heat treatment was carried out. The morphology of the templates and cobalt nanowires was observed using Scanning Electron Microscope (SEM). The magnetic properties of the cobalt nanowires are analyzed using Vibrating Sample Magnetometer (VSM).