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Epoxyresin coated glass slides were used for colloidal particlelithography, in order to prepare well-defined 2D surface arrays. Uponthe assistance of a large-sized 2D colloidal single crystal as template,centimeter-sized ordered surface arrays of bowl-like units were obtained.Systematic studies revealed that the parameters of obtained surfacearrays could be readily controlled by some operational factors, suchas temperature, epoxy resin layer thickness, and template particlesize. With epoxy resin substituting for normal linear polymer, theheight/diameter ratio of bowls in the formed surface arrays can belargely increased. With further reactive plasma etching, the parametersof ordered surface arrays could be finely tuned through controllingetching time. This study provides a facile way to prepare large-sized2D surface arrays with tunable parameters. [ABSTRACT FROM AUTHOR]

Submicrometerhollow microspheres with mesoporous shells were preparedby a simple one-pot strategy. Colloidal silica particles were usedas a particle stabilizer to emulsify the oil phase, which was composedof a polymerizable silicon monomer (TPM) and an inert organic solvent(PEA). The low interfacial tension between colloidal silica particlesand TPM helped to form a Pickering emulsion with small droplet sizes.After the polymerization of TPM, the more hydrophobic PEA formed aliquid core, leading to a hollow structure after its removal by evaporation.BET results indicated that the shell of a hollow particle was mesoporouswith a specific surface area over 400 m2·g–1. With PEA as the core and silica as the shell, each resultant hollowparticle had a hydrophobic cavity and an amphiphilic surface, thusserving as a good colloidal collector for hydrophobic contaminantsin water. [ABSTRACT FROM AUTHOR]

Centimeter-sizedtwo-dimensional (2D) colloidal single crystalsof polystyrene (PS) particles were fabricated at the water/air interfaceby capillary-modulated self-assembly. Different from previous reports,in this work, emulsifier was used to facilitate the stress releaseduring 2D colloidal crystal formation by adjusting the interparticlelateral interactions. With the assistance of compressed nitrogen flow,2D hexagonal colloidal single crystals of centimeter size were obtainedunder appropriate emulsifier concentrations. A new method was also developed to transfer the 2D colloidal crystalsfrom the air/water interface to the desired substrate without obviousdisturbance. This new transferring method was proven not to be sensitiveto surface wettability nor curvature, thus 2D colloidal single crystalswith large areas could be obtained on different kinds of substrate. [ABSTRACT FROM AUTHOR]

A facile method to prepare monodisperse speckled colloidshas beendeveloped via one-step seeded polymerization from noncross-linkedlatex particles. It was found that both cross-linking agents in theadded monomer mixture and charged initiation species are essentialfor the formation of speckles on composite latex particle surfacein seeded polymerization. The size and number density of speckleson the surface are tunable by adjusting the concentration of surfactant.A possible mechanism for the formation of such speckled colloids hasbeen proposed based on a series of control experiments. Speckled colloidalparticles were used as substrates for the adsorption of tobacco mosaicvirus, and a much stronger adsorption was observed compared to smoothparticles, implying a potential application of these speckled particlesin virus collection and more. [ABSTRACT FROM AUTHOR]

Core–shell particles with cross-linked core andshell wereused as seed particles to produce composite Janus particles. It wasfound that when the shell has distinctly higher cross-linking degreethan the core, Janus particles with very unusual structures can beobtained. These particles have two parts, with one part embraced partiallyor entirely by the other part, adjustable by parameters such as phaseratio or cross-linking degree. On the basis of experimental observations,a possible mechanism for the formation of such unusual Janus particleshas been proposed. Janus particles with arms are used to emulsifywater–toluene mixtures, forming oil-in-water (O/W) emulsionsat very high internal phase content with rather low concentrationof particles. Nonspherical emulsion droplets were observed, indicatingthat these Janus particles are likely to jam at the interface, forminga strong protecting layer to stabilize emulsions. [ABSTRACT FROM AUTHOR]