Abstract
We report on inkjet printing of aqueous colloidal suspensions containing monodisperse silica and/or polystyrene nanosphere particles and a systematic study of the morphology of the deposits as a function of different parameters during inkjet printing and solvent evaporation. The colloidal suspensions act as a model ink for an understanding of layer formation processes and resulting morphologies in inkjet printing in general. We investigated the influence of the surface energy and the temperature of the substrate, the formulation of the suspensions, and the multi-pass printing aiming for layer stacks on the morphology of the deposits. We explain our findings with models of evaporation-driven self-assembly of the nanosphere particles in a liquid droplet and derive methods to direct the self-assembly processes into distinct one- and two-dimensional deposit morphologies.Electronic supplementary materialThe online version of this article (doi:10.1186/s11671-015-1065-2) contains supplementary material, which is available to authorized users.
Highlights
Self-assembly processes of molecules or micro- or nanoscopic particles within droplets are an interesting method for the development of ordered assemblies and have attracted considerable interest during the last decades
Employing self-assembly processes for molecules or particles within an evaporating patterned or non-patterned liquid film has turned out to be a simple and elegant method to achieve a packing of the dispersed constituents, e.g., for the assembly of ordered structures from colloidal particles in droplets [10,11,12,13], one-dimensional lines [14, 15], two-dimensional patterned photonic crystals [16], or even three-dimensional spherical colloidal assemblies [17]
Cleaning cycles were introduced during the printing based on a purge process to prevent nozzle clogging or to remove the clogging
Summary
Self-assembly processes of molecules or micro- or nanoscopic particles within droplets are an interesting method for the development of ordered assemblies and have attracted considerable interest during the last decades. During the evaporation of the solvents of the droplet, different transport mechanisms force the molecules or particles to certain positions where they assemble and form in part rigid agglomerates Such explained selfassembly processes are ubiquitous, a natural phenomenon [1,2,3], and considered as a promising tool for nanofabrication [4,5,6]. Numerous publications show the complexity of the fluid dynamics which the particles and constituents undergo aside of Brownian motion [18], gravity [19], and buoyancy during the evaporation Phenomena such as capillary flows [20], convectional flows [21], and the attractive (e.g., van der Waals) and repulsive forces (1) amongst particles [8, 16], (2) between particles and substrate [15, 22, 23], and/or (3) at the three-phase boundary (line-tension effects) [19, 24] will contribute to the final shape of the deposit. The deposits obtained by an evaporating droplet containing nanoparticles on non-absorbent and rigid surfaces can range from uniform patterns [11] to a ring-like pattern via the so-called coffee ring effect [20], central bumps [21], and inner coffee ring deposits [22] or and a number of further patterns in between [9]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
