Dibenzothiophene-S,S-Dioxide-Based Conjugated Polymers: Highly Efficient Photocatalyts for Hydrogen Production from Water under Visible Light

Chunhui Dai; Shidang Xu; Wei Liu; Xuezhong Gong; Majid Panahandeh-Fard; Zitong Liu; Deqing Zhang; Can Xue; Kian Ping Loh; Bin Liu

doi:10.1002/smll.201801839

Dibenzothiophene-S,S-Dioxide-Based Conjugated Polymers: Highly Efficient Photocatalyts for Hydrogen Production from Water under Visible Light

Small. 2018 Aug;14(34):e1801839. doi: 10.1002/smll.201801839. Epub 2018 Jul 24.

Authors

Chunhui Dai¹, Shidang Xu¹, Wei Liu², Xuezhong Gong³, Majid Panahandeh-Fard⁴, Zitong Liu⁵, Deqing Zhang⁵, Can Xue³, Kian Ping Loh², Bin Liu¹

Affiliations

¹ Department of Chemical and Biomolecular Engineering, National University of Singapore, 4 Engineering Drive 4, Singapore, 117585, Singapore.
² Department of Chemistry and Centre for Advanced 2D Materials, National University of Singapore, 3 Science Drive 3, Singapore, 117543, Singapore.
³ School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore.
⁴ Nanoscience & Nanotechnology Initiative (NUSNNI)-Nanocore, National University of Singapore, Singapore, 117576, Singapore.
⁵ Beijing National Laboratory for Molecular Sciences, Organic Solids Laboratory, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China.

PMID: 30039934
DOI: 10.1002/smll.201801839

Abstract

Three dibenzothiophene-S,S-dioxide-based alternating copolymers were synthesized by facile Suzuki polymerization for visible light-responsive hydrogen production from water (> 420 nm). Without addition of any cocatalyst, FluPh2-SO showed a photocatalytic efficiency of 3.48 mmol h^-1 g-¹ , while a larger hydrogen evolution rate (HER) of 4.74 mmol h^-1 g^-1 was achieved for Py-SO, which was ascribed to the improved coplanarity of the polymer that facilitated both intermolecular packing and charge transport. To minimize the possible steric hindrance of FluPh2-SO by replacing 9,9'-diphenylfluorene with fluorene, Flu-SO exhibited a more red-shifted absorption than FluPh2-SO and yielded the highest HER of 5.04 mmol h^-1 g^-1 . This work highlights the potential of dibenzothiophene-S,S-dioxide as a versatile building block and the rational design strategy for achieving high photocatalytic efficiency.

Keywords: conjugated polymers; dibenzothiophene-S,S-dioxide; hydrogen production; visible light irradiation.