• Home
  • UCSC journals portal
  • ANID repository
  • UCSC Thesis Repository
  • English
  • Español
  • Log In
    Have you forgotten your password?
  1. Home
  2. Productividad Científica
  3. Publicaciones Científicas
  4. Insights into the visible light photocatalytic activity of S-doped hydrated TiO2
 
Options
Insights into the visible light photocatalytic activity of S-doped hydrated TiO2
Vorontsov, Alexander V.
Dr. Valdés-Morales, Héctor 
Facultad de Ingeniería 
10.1016/j.ijhydene.2019.05.103
International Journal of Hydrogen Energy
2019
Cationic doping of TiO2 anatase with sulphur represents a facile method to improve catalytic and photocatalytic activity for hydrogen production and extend the action spectrum of TiO2 into the visible light region. However, there is a lot of misunderstanding when trying to explain the experimental findings and suggest theoretical models. In the present computational research work, novel theoretical models are put forward representing fully hydroxylated small anatase nanoparticles with S(IV) and S(VI) doping in various surface positions and in the bulk. It was found that sulfur in the doped anatase nanoparticles preserves its typical coordination geometries of trigonal pyramid for S(IV) and tetrahedron for S(VI). Doping in the anatase surface is much more energetically favorable compared to doping in the bulk. Doping with S(IV) causes decrease of the band gap from 3.22 to 2.65 eV while S(VI) doping could decrease Eg only to 2.96 eV. Location of photogenerated electrons and holes depends strongly on the position of dopant atoms and their valent state. Contrary to some experimental works, no strong and extended visible light absorption bands could be found with cationic doped hydroxylated anatase nanoparticles. However, improved charges separation is observed indeed and causes improved photocatalytic hydrogen production.
S doping
Anatase
Photocatalytic hydrogen production
Decahedral nanoparticles
DFT
DFTB
Ciencias químicas
Ingeniería ambiental
Historial de mejoras
Proyecto financiado por: