Zi Jun Wang

Molecular Structural Design of Conjugated Microporous Poly(Benzooxadiazole) Networks for Enhanced Photocatalytic Activity with Visible Light

A simple structural design principle and band position alignment of conjugated microporous polymers for enhanced photocatalytic efficiency is presented. The valence and conduction band positions of the polymer networks can be fine-tuned by altering the substitution positions on the centered phenyl unit to match the required redox potential of the catalytic reactions under visible light.

Highly porous conjugated polymers for selective oxidation of organic sulfides under visible light

High surface area porous conjugated polymers were synthesized via the high internal phase emulsion polymerization technique and micropore engineering as efficient heterogeneous photocatalysts for highly selective oxidation of organic sulfides to sulfoxides under visible light.

Heterophase Photocatalysts from Water-Soluble Conjugated Polyelectrolytes: An Example of Self-Initiation under Visible Light

We herein report a new design route to stable, heterophase photocatalysts, which function as highly dispersible conjugated polymer nanoparticles and porous monoliths under visible light in aqueous medium. They were constructed by attachment of the ionic-liquid species 1-alkyl-3-vinylimidazolium bromide onto the side chains of a photoactive polymer. The structure configuration allows not only photocatalysis in aqueous environment but also a unique self-initiation radical cross-linking process to transform the water-soluble photoactive polymer into a heterophase system, either as nanoparticles or a porous monolith. High photocatalytic activity and reusability of the heterophase system were demonstrated in the degradation of organic dyes and reduction of Cr(VI) into Cr(III) in water under visible-light irradiation.

Conjugated Microporous Poly(Benzochalcogenadiazole)s for Photocatalytic Oxidative Coupling of Amines under Visible Light

Metal-free visible-light photocatalysts offer a clean, sustainable solution to many pressing environmental issues. Herein, we present a molecular design strategy to fine-tune the valence and conduction band levels of a series of conjugated microporous polymer networks based on poly(benzochalcogenadiazole) for heterogeneous photocatalysis. Enhanced photocatalytic efficiency was observed by altering the chalcogene moieties in the electron-accepting benzochalcogenadiazole unit of the polymer backbone structure. Photooxidative coupling of benzylamines was chosen as a model reaction. This design strategy leading to enhanced efficiency could potentially improve a wide range of photoredox reactions.

Hollow nanoporous covalent triazine frameworks via acid vapor-assisted solid phase synthesis for enhanced visible light photoactivity

Herein, we report a novel trifluoromethanesulfonic acid vapor-assisted solid phase synthetic method to construct nanoporous covalent triazine frameworks with highly ordered hollow interconnected pores under mild reaction conditions. This unique solid state synthetic route allows not only the avoidance of undesired side reactions caused by traditional high temperature synthesis, but also the maintaining of defined and precise optical and electronic properties of the nonporous triazine frameworks. Promising photocatalytic activity of the polytriazine networks was demonstrated in the photoreduction reaction of 4-nitrophenol into 4-aminophenol under visible light irradiation.

A fixed-bed photoreactor using conjugated nanoporous polymer-coated glass fibers for visible light-promoted continuous photoredox reactions

Here, we report on a fixed-bed photoreactor containing conjugated nanoporous polymer-coated glass fibers for visible light-promoted, heterogeneous photoredox reactions in a continuous flow system. A thin film of nanoporous polybenzothiadiazole with a thickness of ca. 80 nm was fabricated directly on the glass fiber with an effective catalyst content of ca. 3.2 wt%. The photocatalytic dehalogenation reaction of α-bromoacetophenones and the enantioselective α-alkylation of aldehydes were carried out in the fixed-bed photoreactor with comparable efficiencies to the state-of-art transition metal-based photocatalysts.