Details

Autor(en) / Beteiligte

• Thanh Truc, Nguyen Thi
• Tran, Dinh Trinh
• Hanh, Nguyen Thi
• Pham, Thanh-Dong

Titel

Novel visible light-driven Nb-doped Ta3N5 sensitized/protected by PPy for efficient overall water splitting

Ist Teil von

• International journal of hydrogen energy, 2018-08, Vol.43 (33), p.15898-15906

Ort / Verlag

Elsevier Ltd

Erscheinungsjahr

2018

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• We successfully synthesized niobium-doped tantalum nitride sensitized/protected by polypyrrole (NbTa3N5/PPy) for efficient overall photocatalytic water splitting to produce hydrogen and oxygen under visible light. Niobium as a dopant was incorporated into the Ta3N5 lattice to act as an intermediate band between the valence band (VB) and the conduction band (CB) of Ta3N5 to enhance the electron-hole pair separation efficiency, thereby enhancing its photocatalytic activity. PPy, a conducting polymer with an extended π-π* conjugated electron system, was used as a sensitizer to enhance the charge transfer efficiency for migration of the photogenerated electrons and holes to its surface to prevent the recombination of the pairs and thus increase their lifetime. The migration of the photogenerated holes to the PPy surface also prevented the self photocorrosion of Ta3N5 (via reaction between the generated holes and nitrides in Ta3N5) in the electrolyte solution and thus enhanced its stability. Therefore, the synthesized NbTa3N5/PPy photocatalyst exhibited very high photocatalytic activity and stability for overall water splitting to produce H2 and O2 even under visible light at production rates of 65.1 and 32.8 μmol g−1cat. h−1, respectively. [Display omitted] •Nb dopant and PPy sensitizer synergistically enhanced the photocatalytic activity of Ta3N5.•Nb dopant enhanced the separation of electrons and holes and prolonged their lifetime.•PPy sensitizer covering Ta3N5 enhanced the charge transfer efficiency of the photocatalyst.•PPy cover protected Ta3N5 from self photocorrosion (oxidation of generated holes).•Under visible light, the NbTa3N5/PPy overall split water to produce both H2 and O2.