Urchin-like TiO2 structures decorated with lanthanide-doped Bi2S3 quantum dots to boost hydrogen photogeneration performance

• Published in: Applied catalysis. B, Environmental Environmental, 2020-09, Vol.272, p.118962, Article 118962
• Main Authors: Miodyńska, Magdalena, Mikolajczyk, Alicja, Bajorowicz, Beata, Zwara, Julia, Klimczuk, Tomasz, Lisowski, Wojciech, Trykowski, Grzegorz, Pinto, Henry P., Zaleska-Medynska, Adriana
• Format: Article
• Language: English
• Subjects: Bismuth sulfide quantum dots; Bismuth sulfides; Decoration; Doped quantum dots; Doping; Energy levels; Erbium; Heterogeneous photocatalysis; Heterojunctions; Hydrogen; Hydrogen evolution; Hydrogen generation; Hydrogen production; Irradiation; Photocatalysis; Quantum dots; Radiation; Titanium dioxide; Ytterbium
• ISSN: 0926-3373; 1873-3883
• DOI: 10.1016/j.apcatb.2020.118962

[Display omitted] •XPS and theoretical studies confirmed the doping of the Bi2S3 QDs by Yb and Er ions.•TiO2 decorated by 10 wt.% of Yb-Bi2S3 QDS allows to produce 1576.7 μmol H2/gcat.•Stability of Yb-Bi2S3 QDs/TiO2 composite in Na2S/Na2SO3 electrolyte was proven. The formation of heterojunctions between wide- and narrow-bandgap photocatalysts is commonly employed to boost the efficiency of photocatalytic hydrogen generation. Herein, the photoactivity of urchin-like rutile particles is increased by decorating with pristine as well as Er- or Yb-doped Bi2S3 quantum dots (QDs) at varied QD loadings (1–20 wt%) and doping degrees (1–15 mol%), and the best hydrogen evolution performance is achieved at Er and Yb contents of 10 mol%. Specifically, a hydrogen productivity of 1576.7 μmol gcat−1 is achieved after 20-h irradiation for TiO2 decorated by 10 mol% Yb-doped Bi2S3 QDs. Theoretical calculations show that the introduction of defects into the Bi2S3 lattice through Er/Yb doping promotes the creation of new energy levels and facilitates the transport of photogenerated charges during photocatalysis.