Comparison of photocatalytic activity and stability of AgBr/Ag/Ag2CO3-mordenite and AgX (X= Cl, I)/Ag/Ag2CO3- mordenite

azadeh asadollahi dobakhshari¹ Shabnam Sohrabnezhad² Reza Ansari³

1) PhD student in Analytical chemistry, Department of Chemistry, Faculty of Science, University of Guilan, Rasht, Iran Email:
2) Associate professor, Department of Chemistry, Faculty of Science, University of Guilan, Rasht, Iran Email:
3) Professor, Department of Chemistry, Faculty of Science, University of Guilan, Rasht, Iran Email:

Publication : 4th International Conference On Research Science And Technology(4rstconf.com)
Abstract :
In this work, AgX (X=Cl, Br, I)/Ag/Ag2CO3 photocatalysts have been successfully synthesized via a facile precipitation method on mordenite (MOR) support. AgX with different weight percentage (20%, 40%, 50% and 60%) were coupled into Ag2CO3. The different amounts of support was investigated. The obtained hybrids were characterized by X-ray diffraction (XRD), UV–vis diffuse reflectance spectroscopy (DRS), transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The DRS results demonstrate plasmonic resonance band of silver NPs in 400-600 region. The following, photocatalytic activity for degradation of methylene blue (MB) was examined by photocatalysts under visible light irradiation. The evaluation of the photocatalytic activity indicates that AgX (X= Br, I)/Ag/Ag2CO3-MOR exhibits higher photocatalytic degradation efficiency for degradation of MB under visible light irradiation than AgCl/Ag2CO3-MOR, Ag2CO3-MOR and Ag2CO3. The recycling tests indicates that the stability of AgBr/Ag/Ag2CO3-MOR is higher than the AgI/Ag/Ag2CO3-MOR. The cycle experiments show after the formation of heterojunction between AgBr and Ag2CO3, the stability of the catalyst improved significantly, the photocatalytic activity of the catalyst after 4 recycling runs is changed slightly, suggesting that the AgBr/Ag/Ag2CO3 photocatalyst hybrid has high stability. The photocatalytic degradation for 100 ml of MB solution (CMB=10-5M) by AgBr/Ag/Ag2CO3-mordenite (20 wt%, 40% wt%, 50% wt%) samples was 80%, 74.24% and 91.5% with 0.07g photocatalyst at 85 min, respectively. The stability of nanocomposite was investigated by cycle experiments. The results exhibited the degradation capacity maintained 77.85% after four cycles, indicating a desirable stability.
Keywords : photocatalyst AgX (X=Cl Br I)/Ag/Ag2CO3 Ag2CO3-MOR stability