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The search for metal-free organic photocatalysts for H2 production from water using visible light remains a key challenge. Reported herein is a molecular structural design of pure organic photocatalysts, derived from conjugated polybenzothiadiazoles, for photocatalytic H2 evolution using visible light. By alternating the substitution position of the electron-withdrawing benzothiadizole unit on the phenyl unit as a comonomer, various polymers with either one- or three-dimensional structures were synthesized and the effect of the molecular structure on their catalytic activity was investigated. Photocatalytic H2 evolution efficiencies up to 116 μmol h(-1) were observed by employing the linear polymer based on a phenyl-benzothiadiazole alternating main chain, with an apparent quantum yield (AQY) of 4.01 % at 420 nm using triethanolamine as the sacrificial agent., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Polyfluorene-bearing bromohexyl side chains are quaternized by 1-vinylimidazole in order to attach dialkylimidazolium bromide ionic liquid (IL) species along the conjugated backbone. Subsequently, polyfluorene polyelectrolyte nanoparticles (NPs) of 40 nm in average size are created via radical cross-linking of the pendant vinylimidazolium groups. Anion exchange from Br(-) to BF(4)(-), PF(6)(-), and bis(trifluoromethylsulfonyl)imide anion (TFSI(-) renders NPs adjustable dispersability in various organic solvents. The hydrophobic-conjugated backbone and the hydrophilic dialkylimidazolium bromide IL moieties depict an amphiphilic profile, which allows the NPs to be deployed as conductive stabilizer in the emulsion polymerization of styrene. The resultant latexes are fluorescent, tunable in size and can be transferred to organic solvents without forfeiting their colloidal stability., (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)