Ligand-free fabrication of Au/TiO2 nanostructures for plasmonic hot-electron-driven photocatalysis: Photoelectrochemical water splitting and organic-dye degredation

Celebi N., Aydin M. Y., Soysal F., Çiftci Y., Salimi K.

JOURNAL OF ALLOYS AND COMPOUNDS, cilt.860, 2021 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 860
  • Basım Tarihi: 2021
  • Doi Numarası: 10.1016/j.jallcom.2020.157908
  • Dergi Adı: JOURNAL OF ALLOYS AND COMPOUNDS
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, PASCAL, Aerospace Database, Chemical Abstracts Core, Communication Abstracts, INSPEC, Metadex, Public Affairs Index, Civil Engineering Abstracts
  • Anahtar Kelimeler: TiO2, Gold nanoparticles, Photocatalysis, H-2 generation, Water splitting
  • Gazi Üniversitesi Adresli: Evet

Özet

Herein, an alternative/cost-effective simple synthesis route was accurately designed to fabricate ligand-free Au/TiO2 Schottky contacts. This time-saving technique provided one-step binding of pre-synthesized NaBH4 stabilized colloidal Au NPs thanks to oxygen vacancies on the rutile phase. The strong/close conjugation provided an ideal plasmon-sensitive heterostructures with desired SPR excited charge separation to explore a strategy for an enhanced photoelectrochemical (PEC) water splitting and organicdye photodegradation. Toward the plasmonic hot-electron driven PEC water splitting, the highest photocurrent density was obtained as 1.87 mA/cm(2) for Au-2x/TiO2 at low potential 0.187 V vs RHE under visible-LED light illumination (30 mW/cm(2)) which is 6.6-fold higher than bare TiO2 (0.28 mA/cm(2)). This superior PEC performance was recorded with low amount of Au loading (0.154 wt%) and very low light intensity (visible-LED light illumination; 30 mW/cm(2)). Additionally, owing to the advantages of newly synthesized Au/TiO2 Schottky contacts, an enhanced photocatalytic activity was recorded with 97% decolorization of methylene blue (MB) during 150 min under visible LED light illumination. This novel fabrication strategy provided a next generation of visible light responsive heteronanostructures with no need for additional pre-fabrication procedures with potential large-scale PEC water splitting applications. (C) 2020 Elsevier B.V. All rights reserved.