A thermolytic route to a polysilyne

We report a safe and convenient method to prepare a new class of network polysilane, or polysilyne ([RSi]_n). Simple thermolysis of a readily accessible linear poly(phenylsilane), [PhSiH]_n, affords polysilyne [PhSi]_n with concomitant evolution of monosilanes. This new polymer shows a hyperbranched structure with unique features not observed in known polysilynes prepared via hazardous Wurtz coupling routes. Despite these differences, our soluble, yellow polysilyne exhibits some important properties associated with the traditional random network structure: it absorbs up to 400 nm in the UV spectrum, yet is stable to photolysis under inert atmosphere. This efficient new synthetic route opens the door to exciting applications for these hyperbranched polymers in materials and device technologies.

Preparation of a silver nanoparticle-based dual-functional sensor using a complexation–reduction method

A dual-functional sensor based on silver nanoparticles was synthesized by a two-stage procedure consisting of a low-temperature chitosan–Ag⁺ complexation followed by a high-temperature reduction of the complex to form chitosan-capped silver nanoparticles (CS-capped Ag NPs).