TiO2modified with monometallic (Au or Pt) and bimetallic (Au/Pt) nanoparticles have been preparedusing a water-in-oil microemulsion system (water/AOT/cyclohexane) followed by calcination step. Theeffect of metal ratio, reducing agent type (NaBH4or N2H4), TiO2matrix type (P-25, ST-01, TiO-5, TiO2nano-tubes or TiO2obtained by TIP hydrolysis) as well as calcination temperature (from 350 to 650◦C) weresystematically investigated. Obtained photocatalysts were characterized by UV–vis diffuse-reflectancespectroscopy (DRS), BET surface area measurements, scanning transmission microscopy (STEM), X-raydiffraction analysis (XRD), and X-ray photoelectron spectroscopy (XPS). Photocatalytic activity undervisible light ( > 420 nm) has been estimated in phenol degradation reaction in aqueous phase. Theresults showed that phenol degradation rate under visible light in the presence of TiO2loaded with Au/Ptnanoparticles differed from 0.7 to 2.2 mol dm−3min−1for samples prepared using different reducingagent. Sodium borohydride (NaBH4) favors formation of smaller Au/Pt nanoparticles and higher amountgold in Au/Pt is in the form of electronegative species (Auı−) resulted in higher photoactivity. TiO2obtained by TIP hydrolysis in microemulsion system seems to be the best support for Au/Pt nanoparticlesfrom all among investigated matrix. It was also observed that enhancement of calcination temperaturefrom 450 to 650◦C resulted in rapid drop of Au/Pt-TiO2photoactivity under visible light due to surfacearea shrinkage, crystal structure change and probably change in Au/Pt nanoparticles morphology.
Authors
- mgr inż. Anna Gołąbiewska link open in new tab ,
- Wojciech Lisowski,
- Marcin Jarek,
- Grzegorz Nowaczyk,
- prof. dr hab. inż. Anna Zielińska-Jurek link open in new tab ,
- prof. dr hab. inż. Adriana Zaleska-Medynska link open in new tab
Additional information
- Category
- Publikacja w czasopiśmie
- Type
- artykuł w czasopiśmie wyróżnionym w JCR
- Language
- angielski
- Publication year
- 2014
