Urchin-like TiO2 structures decorated with lanthanide-doped Bi2S3 quantum dots to boost hydrogen photogeneration performance
Magdalena Miodyńska, Alicja Mikołajczyk, Beata Bajorowicz, Julia Zwara, Tomasz Klimczuk, Wojciech Lisowski, Grzegorz Trykowski, Henry P. Pinto, Adriana Zaleska‐Medynska
Abstract
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.