Phosphate ester functionalized fluorene-benzothiadiazole alternating copolymer/hydroxylated g-CN heterojunctions for efficient hydrogen evolution under visible-light irradiation.

It is highly desirable to explore functionalized polymer semiconductor/g-CN heterojunction photocatalysts with the tight interfacial connection for promoting the photogenerated electron-hole pair separation, improving the hydrophilicity, extending the visible light response and achieving the efficient visible light-driven H evolution. Herein, we synthesized novel poly[9,9-bis(3-ethyl phosphate propyl)fluorene-alt-benzothiadiazole] (PPFBT) with a phosphate ester on every repeating unit by the Suzuki polymerization and then fabricated PPFBT/hydroxylated g-CN (PPFBT/CN-OH) heterojunctions via a surface hydroxyl-induced assembly process. The ratio-optimized 5PPFBT/CN-OH shows the hydrogen evolution activity of 2662.

Improved Visible-Light Photocatalytic H Evolution of G-CN Nanosheets by Constructing Heterojunctions with Nano-Sized Poly(3-Thiophenecarboxylic Acid) and Coordinating Fe(III).

It is highly desirable to enhance the photogenerated charge separation of g-CN by constructing efficient heterojunctions, especially with an additional organic constitution for solar-hydrogen conversion. Herein, g-CN nanosheets have been modified controllably with nano-sized poly(3-thiophenecarboxylic acid) (PTA) through in situ photopolymerization and then coordinated with Fe(III) via the -COOH groups of modified PTA, forming an interface of tightly contacted nanoheterojunctions between the Fe(III)-coordinated PTA and g-CN. The resulting ratio-optimized nanoheterojunction displays a ~4.

Controlled Synthesis of Nitro-Terminated Oligothiophene/Crystallinity-Improved g-CN Heterojunctions for Enhanced Visible-Light Catalytic H Production.

It is highly desired to explore closely contacted polymer semiconductor/g-CN heterojunction photocatalysts with promoted photogenerated-carrier separation and extended visible-light response for efficient visible-light-driven H production. Here, we first synthesized the nitro-terminated oligothiophene (OTh) by the controlled copolymerization of thiophene and 2-nitrothiophene monomers, then constructed the nitro-terminated oligothiophene/crystallinity-improved g-CN (OTh/g-CN) heterojunctions by a grinding-induced combination strategy. The ratio-optimized 20OTh/g-CN shows highly efficient H production activity up to 3.