Template syntheses of polypyrrole nanowires and CdS nanoparticles in porous polymer monoliths

Template synthesis is a powerful method for the preparation of nanoscale materials with specific size and shape. We describe the template synthesis of polypyrrole nanowires and CdS nanoparticles within monolithic nanoporous polymer templates prepared from ordered block copolymer precursors. SAXS measurements confirmed retention of the host structure after growth of the nanomaterials within the pores of the template. SEM and TEM were used for direct visualization of the size and shape of the templated materials both in the monolith as well as after removal of the template through dissolution. The size of the templated nanomaterials matched that of the template pores and was modifiable by using templates containing different pore dimensions. For the case of CdS nanoparticles, WAXS was also used to verify particle size and crystal structure. In an effort to impregnate the nanoporous monoliths with CdS particles smaller than the pore dimensions of the template, a synthetic protocol utilizing a capping agent was employed. These particles were shown to exhibit a quantum size effect by DR-UV-Vis.