Solar-light-driven Z-scheme CaF2:Yb3+,Er3+@ZnTiO3/Au/CdS photocatalyst with efficient charge transfer and light utilization for enhanced norfloxacin degradation with simultaneous hydrogen evolution

A novel Z-scheme CaF 2 :Yb 3+ ,Er 3+ @ZnTiO 3 /Au/CdS photocatalyst has been prepared. In this system, an excellent up-conversion luminescent agent, CaF 2 :Yb 3+ ,Er 3+ , is introduced to broaden the light response range. The Au surface plasmon resonance effect endows the system with highly efficient charge transfer. The photocatalytic activity of the Z-scheme CaF 2 :Yb 3+ ,Er 3+ @ZnTiO 3 /Au/CdS photocatalyst has been evaluated in the degradation of norfloxacin (NOR) with simultaneous hydrogen production . Some influencing factors, such as solar light irradiation time, sacrificial agent concentration, and number of reuse cycles, are discussed. The emission spectrum and energy conversion mechanism of CaF 2 :Yb 3+ ,Er 3+ have also been studied. The prepared photocatalyst facilitated a significant degree of degradation (92.05%) of NOR and considerable hydrogen production (513.39 μmol/g) under solar light irradiation for 5.0 h. Moreover, it showed high stability in photocatalytic NOR degradation with simultaneous hydrogen production over five cycles. A possible mechanism for photocatalytic degradation of NOR with simultaneous hydrogen production promoted by the Z-scheme CaF 2 :Yb 3+ ,Er 3+ @ZnTiO 3 /Au/CdS photocatalyst is proposed.