J. Mater. Sci. Technol. ›› 2026, Vol. 250: 219-232.DOI: 10.1016/j.jmst.2025.05.058

• Research article • Previous Articles     Next Articles

Unravelling the critical role of biomass carbon dots in atomic co-sharing Sb2S3/Sb2WO6 heterojunctions: Boosting photocatalytic water purification via precise dual-electric field

Li Zhaoa, Yuanping Liua, Wenwen Qua,b,c,*, Bing Shena, Shu Yangd,*   

  1. aFaculty of Science, Kunming University of Science and Technology, Kunming 650500, China;
    bKey Laboratory of Unconventional Metallurgy, Ministry of Education, Kunming University of Science and Technology, Kunming 650093, China;
    cNational Local Joint Laboratory of Engineering Application of Microwave Energy and Equipment Technology, Kunming University of Science and Technology, Kunming 650093, China;
    dSchool of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming 650500, China
  • Received:2025-02-28 Revised:2025-04-16 Accepted:2025-05-05 Published:2026-04-10 Online:2025-07-04
  • Contact: *E-mail addresses: qwwen1977@126.com (W. Qu), 276757401@qq.com (S. Yang).

Abstract: Developing an efficient, recyclable, and sustainable photocatalyst is crucial for the removal of both inorganic and organic pollutants in water matrices. In this study, N-doped biomass carbon dots (NCDs) sensitized Sb2S3/Sb2WO6 (NCSSWO) heterostructures were constructed for simultaneously photocatalytic removals of Cr(Ⅵ) and ofloxacin under 10 W LED irradiation using an in-situ microwave-assisted ion exchange method. The optimal NCSSWO-1 exhibited superior performance for both Cr(Ⅵ) and ofloxacin elimination, yielding up to 24.1 and 1.9 times greater Cr(Ⅵ) and ofloxacin rate constants, respectively, than pristine Sb2WO6. Notably, the ability of NCSSWO-1 to remove Cr(Ⅵ) and ofloxacin in co-existing systems is evidently better than in single-pollutant systems. Experimental and theoretical analyses reveal the prominent activity is attributed to multiple roles caused by the formation of an intense dual-electric field. Specifically, the Sb-S/Sb-O bonds at Sb2S3-Sb2WO6 heterointerface endow atomic co-sharing electron channel for accelerating charge separation. Moreover, the NCDs are imperative for the charge-oriented accumulation near the Sb2WO6 side via van der Waals interactions and provide extra light-harvesting and reactive centers. Additionally, the ofloxacin decomposition process, intermediate biotoxicity, and catalytic mechanism were confirmed. This synergistic eradication strategy of constructing dual Z-scheme heterostructure via interfacial engineering offers valuable insight into developing ternary-based photocatalysts for efficient environment purification.

Key words: NCDs/Sb2S3/Sb2WO6, Dual Z-scheme heterostructure, Atomically co-sharing, Photocatalytic environmental remediation, Synergistic effect