title: Electrochemical self-assembly of highly oriented ZnO-surfactant hybrid multilayers.
abstract: Highly oriented zinc oxide-surfactant hybrid multilayers were electrochemically self-assembled on silicon substrates from Zn(NO3)2 solutions containing extremely low concentration of sodium dodecyl sulfate (SDS). The X-ray diffraction results showed that the structure of the hybrid film is sensitive to the concentration of SDS. When the concentration of SDS is below a critical value, 0.002 wt %, a surfactant bilayer is adsorbed on the silicon surface, together with electrodeposited crystalline ZnO particles. Above this concentration, lamellar ZnO-surfactant hybrid films are formed, the period of which decreases from 31.7 +/- 0.2 A at 0.003 wt % to 27.5 +/- 0.2 A at 0.005 wt %, another critical concentration. It then increases monotonically and reaches its maximum of 33.0 +/- 0.2 A above 0.05 wt %. The results implied that the kinetics of the electrochemical self-assembly depends on the relative speed of the reduction of the zinc ions and the aggregation of the surfactant. The two processes occur cooperatively at the electrolyte-electrode interface to form the hybrid films.
authors.affiliation: Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100080, China.
authors.forename: Huai-Yu
authors.initials: HY
authors.lastname: Jing
authors.forename: Xiao-Long
authors.initials: XL
authors.lastname: Li
authors.forename: Ying
authors.initials: Y
authors.lastname: Lu
authors.forename: Zhen-Hong
authors.initials: ZH
authors.lastname: Mai
authors.forename: Ming
authors.initials: M
authors.lastname: Li