Louis, MO, USA) in 18 MΩ deionized water. The surface-activated graphite substrate is vertically kept in this solution in the autoclavable glass bottle and held steady at 95°C for 8 hours. This hydrothermal procedure

results in the dissociation of Zn(II)-amino complex resulting in ZnO which grows as ZnO nanorods [47]. Post deposition, the graphite Palbociclib in vitro substrates are rinsed in deionized water to remove any residual precursor chemicals and dried in air. Pulsed current electropolymerization of polypyrrole sheath and nanotube formation A uniform and conformal deposition of polypyrrole of a controlled thickness over ZnO nanorods is essential for the creation of PPy sheath and nanotube nanostructures. Polypyrrole has been deposited the past

by various chemical [48] and potentiostatic electropolymerization click here [49] methods. In this work, PPy deposition is done by electropolymerization of pyrrole monomer in situ over ZnO nanorods using the ultrashort multiple unipolar pulsed-current method reported earlier [45]. Electropolymerization is accomplished in an electrolyte solution containing 0.01 M pyrrole (Py) monomer (Sigma-Aldrich) and 0.1 M lithium perchlorate dopant ions in the presence of 0.06 M sodium dodecyl sulfate (SDS) surfactant. The preparatory steps involve first the dissolution of pyrrole monomer in the presence of SDS under continuous stirring in deionized water warmed to 40°C. Later, the ZnO-seed-layer-coated graphite substrate is dipped vertically for approximately 20 min in this solution which helps in the wettability of the ZnO nanorods with pyrrole monomer. Before initiating the electropolymerization process, lithium perchlorate is added to form 0.1 M solution. The formation of the polypyrrole sheath layer over ZnO nanorods is carried out by pulsed current electropolymerization

method in a two-electrode cell using a platinum (Pt) sheet as a counter and a reference electrode. In this method, multiple unipolar anodic ultrashort 10-ms-duration constant-current pulses of amplitude 4 mA.cm-2 are applied. Each of the pulses is Thiamet G interspaced by a current ‘off’ period of 100-ms duration. The electropolymerization is initiated during the pulse ‘on’ period as the corresponding anodic potential exceeds the oxidation potential of the pyrrole monomer. The current off period essentially helps create the equilibrium conditions in the vicinity of ZnO nanorods for deposition under homogenous polymerization conditions. The number of current pulses effectively controls the polypyrrole-layer thickness and usually approximately 5 to 10 k pulses were used to form fully covered PPy sheath over ZnO nanorods. In some cases 20 k pulses were also applied to form a thicker PPy sheath. The PPy nanotube structure is obtained by etching away the vertically aligned ZnO nanorod core in a 20% ammonia solution [36].