Symmetry‐breaking of Dibenzo[b,d]thiophene Sulfone Enhancing Polaron Generation for Boosted Photocatalytic Hydrogen Evolution

• Published in: Angewandte Chemie International Edition Vol. 63; no. 32; pp. e202407702 - n/a
• Main Authors: Lin, Wei‐Cheng, Wu, Yi‐Hsiang, Sun, Yu‐En, Elsenety, Mohamed M., Lin, Wan‐Chi, Yen, Jui‐Chen, Hsu, Hung‐Kai, Chen, Bo‐Han, Huang, Hung‐Yi, Chang, Chia‐An, Huang, Tse‐Fu, Zhuang, Ying‐Rang, Tseng, Yuan‐Ting, Lin, Kun‐Han, Yang, Shang‐Da, Yu, Chi‐Hua, Chou, Ho‐Hsiu
• Format: Journal Article
• Language: English
• Published: Germany 05.08.2024
• Subjects: Benzo[b]benzo[4,5]thieno[2,3-d]thiophene 5,5-dioxide; Photocatalytic hydrogen evolution; Polarizability; Polaron population; Symmetry-breaking; Benzo[b]benzo[4,5]thieno[2,3-d]thiophene 5,5-dioxide; Photocatalytic hydrogen evolution; Polarizability; Polaron population; Symmetry-breaking
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.202407702

The current bottleneck in the development of efficient photocatalysts for hydrogen evolution is the limited availability of high‐performance acceptor units. Over the past nine years, dibenzo[b,d]thiophene sulfone (DBS) has been the preferred choice for the acceptor unit. Despite extensive exploration of alternative structures as potential replacements for DBS, a superior substitute remains elusive. In this study, a symmetry‐breaking strategy was employed on DBS to develop a novel acceptor unit, BBTT‐1SO. The asymmetric structure of BBTT‐1SO proved beneficial for increasing multiple moment and polarizability. BBTT‐1SO‐containing polymers showed higher efficiencies for hydrogen evolution than their DBS‐containing counterparts by up to 166 %. PBBTT‐1SO exhibited an excellent hydrogen evolution rate (HER) of 222.03 mmol g−1 h−1 and an apparent quantum yield of 27.5 % at 500 nm. Transient spectroscopic studies indicated that the BBTT‐1SO‐based polymers facilitated electron polaron formation, which explains their superior HERs. PBBTT‐1SO also showed 14 % higher HER in natural seawater splitting than that in deionized water splitting. Molecular dynamics simulations highlighted the enhanced water‐PBBTT‐1SO polymer interactions in salt‐containing solutions. This study presents a pioneering example of a substitute acceptor unit for DBS in the construction of high‐performance photocatalysts for hydrogen evolution. This study presents BBTT‐1SO, a novel acceptor unit designed by breaking the symmetry of dibenzo[b,d]thiophene sulfone (DBS). Its asymmetric structure enhances octapole moment and polarizability compared to DBS‐containing counterparts. Transient spectroscopy demonstrates efficient generation of electron polarons in BBTT‐1SO polymers, contributing to their superior hydrogen evolution rate compared to DBS‐containing polymers.