Efficient photocatalytic production of hydrogen by exploiting the polydopamine-semiconductor interface

• Published in: Applied catalysis. B, Environmental Environmental, 2021-01, Vol.280, p.119423, Article 119423
• Main Authors: Kim, Yeonho, Coy, Emerson, Kim, Heejin, Mrówczyński, Radosław, Torruella, Pau, Jeong, Dong-Won, Choi, Kyung Soon, Jang, Jae Hyuck, Song, Min Young, Jang, Du-Jeon, Peiro, Francesca, Jurga, Stefan, Kim, Hae Jin
• Format: Article
• Language: English
• Subjects: Air purification; Carrier recombination; Current carriers; Disinfection; Heterojunctions; Heterostructure; Heterostructures; Hydrogen production; Nanorods; Optoelectronics; Photocatalysis; Photocatalysts; Photocorrosion; Polydopamine; Recombination; Valence band; Zinc sulfide
• ISSN: 0926-3373; 1873-3883
• DOI: 10.1016/j.apcatb.2020.119423

[Display omitted] •Heterojunction comprising of ZnS nanostructures and ultrathin polydopamine shows an enhanced H2 production performance.•Improvement of the photostability of sulfur-based photocatalyst towards hydrogen production and environmental remediation.•Introducing interfacial ZnS1-xOx and polydopamine gives rise to the effective separation, transport, and tunneling of charge carriers.•A thin polydopamine layer allows the tunneling of photoelectrons, improves the wettability of catalysts, and provides a passivating surface. Photocatalytic hydrogen (H2) production on zinc sulfide (ZnS) still remains unsatisfactory because of the fast charge carrier recombination through direct-bandgap and photocorrosion by oxidative holes at the valence band. Here we report on a strongly coupled heterojunction photocatalyst (ZnS/PDA) comprising by a ZnS nanorod and ultrathin polydopamine (PDA). The ZnS/PDA exhibits H2 production rate of 2162.5 μmol h−1  g−1, and 78.7 % of this initial photoactivity is sustained after consecutive running for 24 h. A double staggered heterostructure by interfacial zinc oxysulfide and 1 nm-thick PDA layer gives rise to the effective separation, transport, and tunneling of charge carriers for robust H2 production without the trade-off between photocatalytic stability and activity. We anticipate that the present ZnS/PDA can be exploitable in other catalytic applications, such as disinfection of bacteria and air purification. Furthermore, easy modification of optoelectronic properties by PDA will be applicable to a wide range of materials.