Mechanochromic Displays Based on Photoswitchable Cholesteric Liquid Crystal Elastomers.

Stimuli responsive optical materials are attractive for many areas, from healthcare to art design. However, creating intricate color-changing patterns for visual information is still a challenge. This work describes the preparation of mechanochromic structural colored intricate pictures imprinted in cholesteric liquid crystal elastomers by using a chiral isosorbide molecular photoswitch.

Sticky Multicolor Mechanochromic Labels.

Sticky-colored labels are an efficient way to communicate visual information. However, most labels are static. Here, we propose a new category of dynamic sticky labels that change structural colors when stretched.

Three-dimensional printing of photonic colloidal glasses into objects with isotropic structural color.

Structural color is frequently exploited by living organisms for biological functions and has also been translated into synthetic materials as a more durable and less hazardous alternative to conventional pigments. Additive manufacturing approaches were recently exploited for the fabrication of exquisite photonic objects, but the angle-dependence observed limits a broader application of structural color in synthetic systems. Here, we propose a manufacturing platform for the 3D printing of complex-shaped objects that display isotropic structural color generated from photonic colloidal glasses.

An Efficient Substrate-Free Method of Producing SiO-Based Nanoparticles for Superhydrophobic Applications.

We report on the preparation of SiO-based nanoparticles readily available for superhydrophobic applications. In contrast to usual approaches, our process is substrate-free and based on electrostatic adsorption of small SiO particles onto large SiO cores with the aid of poly(diallyldimethylammonium chloride) followed by calcination and chemical modification with trichlorododecylsilane. The as-prepared nanoparticles are in powder form and exhibit stable superhydrophobic behavior at room temperature because of the unique combination between the hierarchical raspberry-like structure and low surface energy.

Effect of Structural Features on the Superhydrophobicity of SiO-Based Coatings.

A detailed correlation between topographical features and wettability of chemically modified coatings based on silica nanoparticles (SiO) was performed. In this study, hierarchical structures were prepared by the layer-by-layer (LbL) technique using two different approaches: random roughened surfaces were obtained by exploring stacking defects spontaneously arisen after 15, 30, and 45 assembly cycles of 22 nm SiO, and a particular structure, commonly known as raspberry-like, was obtained by depositing 22 nm SiO over the first deposited 400 nm SiO. As an intrinsic attribute of the assembly process, the average slope of random roughened surfaces seems to be constant and virtually independent of the number of deposited layers.