1 research outputs found
Simultaneous Formation and Spatial Patterning of ZnO on ITO Surfaces by Local Laser-Induced Generation of Microbubbles in Aqueous Solutions of [Zn(NH<sub>3</sub>)<sub>4</sub>]<sup>2+</sup>
We
demonstrate the simultaneous formation and spatial patterning of ZnO
nanocrystals on an indium–tin oxide (ITO) surface upon local
heating using a laser (1064 nm) and subsequent formation of microbubbles.
Laser irradiation of an ITO surface in aqueous [ZnÂ(NH<sub>3</sub>)<sub>4</sub>]<sup>2+</sup> solution (1.0 × 10<sup>–2</sup> M at pH 12.0) under an optical microscope produced ZnO nanocrystals,
the presence of which was confirmed by X-ray diffraction analysis
and Raman microspectroscopy. Scanning the focused laser beam over
the ITO surface generated a spatial ZnO pattern (height: ∼60
nm, width: ∼1 μm) in the absence of a template or mask.
The Marangoni convection generated in the vicinity of the microbubbles
resulted in a rapid concentration/accumulation of [ZnÂ(NH<sub>3</sub>)<sub>4</sub>]<sup>2+</sup> around the microbubbles, which led to
the formation of ZnO at the solid–bubble–solution three-phase
contact line around the bubbles and thus afforded ZnO nanocrystals
on the ITO surface upon local heating with a laser