Zirconium dioxide nanopowders with incorporated Si4+ions asefficient photocatalyst for degradation of trichlorophenol usingsimulated solar light

Abstract

We present a hydrothermal method for synthesis of zirconia nanopowders: pure and with incorporatedSi4+ions. Zirconyl chloride and tetraethyl orthosilicate were used as precursors. As prepared powderswere annealed at 600◦C and characterized using structural (XRD), morphological (SEM and TEM) andoptical techniques (UV/vis DR, FTIR and photoluminescence spectroscopy). Their textural properties(BET method) and photocatalytic activity toward degradation of model compounds (tricholophenol andRhodamine B) using simmulated solar light were obtained. We showed that by using hydrothermal syn-thesis method pure monoclinic ZrO2highly crystalline powder can be obtained. Incorporation of Si4+ionsinduced stabilization of tetragonal crystalline phase at room temperature and decreasing of particle sizes.Incorporation of Si4+ions in zirconia matrix also resulted in increase of specific area of nanopowders. FTIRmeasurements were used as proof for existence of Zr O Si bond. Effective band gap of zirconia pow-ders was reduced from 5 (pure ZrO2) to 3.8 eV for samples with Si4+ions. All zirconia powders showedsignificant photocatalytic activity regarding degradation of triclorophenol and no activity regarding RB(Rhodamine B dye). Photocatalytic activity of zirconia was increased by incorporation of Si ions in thehost matrix. The source of this observation is discussed correlating all obtained properties of pure andSi-incorporated nanopowders. Optimization of synthesis parameters and composition of zirconia sam-ples obviously can lead to their photocatalytic activity comparable to Degussa TiO2powder, famous andcommercial photocatalyst.