Photochromic spiropyran-embedded PDMS for highly sensitive and tunable optochemical gas sensing.

A highly sensitive, tunable, flexible and microfluidic compatible gas sensor was developed based on a photochromic spiropyran-embedded PDMS composite.

Polydiacetylenes: supramolecular smart materials with a structural hierarchy for sensing, imaging and display applications.

While a large variety of conjugated polymers exist, polydiacetylenes (PDAs) remain a major research area among scientists due to their interesting optical, spectral, electronic, and structural properties. Heavily reviewed in regards to their stimuli responsive properties, much is known about the assortment of sensing and detection capabilities of PDAs. In this article, we look more upon the structural diversities of polydiacetylenes that have been achieved in recent years, particularly from a hierarchical perspective of 1, 2, and 3-dimensional configurations.

Inkjet printing of conjugated polymer precursors on paper substrates for colorimetric sensing and flexible electrothermochromic display.

Inkjet-printable aqueous suspensions of conjugated polymer precursors are developed for fabrication of patterned color images on paper substrates. Printing of a diacetylene (DA)-surfactant composite ink on unmodified paper and photopaper, as well as on a banknote, enables generation of latent images that are transformed to blue-colored polydiacetylene (PDA) structures by UV irradiation. Both irreversible and reversible thermochromism with the PDA printed images are demonstrated and applied to flexible and disposable sensors and to displays.

Fabrication of Patterned Polydiacetylene Composite Films Using a Replica-Molding (REM) Technique.

Functional three-dimensional (3D) micropatterns of diacetylene supramolecules embedded in a host polymer have been successfully fabricated by a replica-molding (REM) technique. Dimensional reduction as a result of liquid evaporation during the curing process does not affect the conformational features of the transferred patterns. Polymerization of the diacetylene vesicles using 254 nm UV-light irradiation from the back-side of the transparent substrate induces blue colored polydiacetylene (PDA) micro-images.

A cauliflower-like gold structure for superhydrophobicity.

We present a two-step route to produce a hierarchical cauliflower-like gold structure that involves the adsorption of gold nanoparticles described by the random sequential adsorption (RSA) model, followed by the electrochemical growth on the surfaces of the primary gold nanoparicles. The structure was confirmed using scanning electron microscopy (SEM), energy dispersive spectrometer analysis (EDS), and X-ray diffraction (XRD). After fluoroalkylsilane modification, the cauliflower-like structured surface exhibits a high contact angle and a low sliding angle.

Direct electrochemistry of uric acid at chemically assembled carboxylated single-walled carbon nanotubes netlike electrode.

Carboxylated single-walled carbon nanotubes (SWCNT) chemically assembled on gold substrate was employed as netlike electrode to investigate the charge-transfer process and electrode process kinetics using uric acid as an example. The electrochemical behavior of uric acid in carboxylated SWCNT system was investigated using cyclic voltammetry, chronoamperometry, and single potential time-based techniques. The properties of raw SWCNT electrode were also studied for comparison purpose.