A Novel Ag2O/Fe–TiO2 Photocatalyst for CO2 Conversion into Methane Under Visible Light

  • N. R. KhalidEmail author
  • M. Khalid Hussain
  • G. Murtaza
  • M. IkramEmail author
  • M. Ahmad
  • A. Hammad


Modified TiO2 based nanomaterials have attained significant interest because of their unique morphology and excellent optical and photocatalytic properties. In this research, a very novel and highly efficient Ag2O/Fe–TiO2 porous structure was developed by simple hydrothermal method. The structural and morphological properties of the photocatalysts were studied by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The surface areas of the samples were measured by Brunauer–Emmett–Teller theory (BET). The chemical composition and optical properties were investigated using X-ray photoelectron spectroscopy (XPS) and UV–visible spectroscopy. The optical absorption measurements show a clear red-shift in absorption edge of Fe–TiO2 after loading of Ag2O (Ag2O/Fe–TiO2 composite). Moreover, Ag2O varying ratio (0–15 at.%) has also enhanced the efficiency of Ag2O/Fe–TiO2 photocatalyst for CO2 conversion into methane under visible light illumination (λ ≥ 420 nm). The optimum ratio of Ag2O loading which exhibited maximum performance is 10 at.%. Moreover, the 10%Ag2O/Fe–TiO2 composite synthesized at 180 °C hydrothermal temperature showed an excellent increase in photocatalytic activity than other composites synthesized at 150 and 210 °C. This excellent performance of photocatalyst can be attributed to the highly porous petal-like structure of composite. Therefore, it is expected that the present study will be a good addition in literature for designing highly active photocatalytic materials for reduction of CO2 into useful hydrocarbons.


TiO2 Hydrothermal method Photocatalysis CO2 conversion Methane formation 



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Authors and Affiliations

  1. 1.Department of PhysicsUniversity of GujratGujratPakistan
  2. 2.Centre for Advanced Studies in PhysicsGC UniversityLahorePakistan
  3. 3.Department of PhysicsGC UniversityLahorePakistan
  4. 4.Department of PhysicsCOMSATS University IslamabadLahorePakistan

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