Enhanced solar photocatalytic activity of Er3+:YAlO3-loaded BiPO4 composite

Er3+:YAlO3 loaded BiPO4 were successfully synthesized by a simple heat treatment approach in order to enhance the photocatalytic efficiency of BiPO4. Comparing with the simple substance of BiPO4, the composite system showed the better efficiency on photodegradation of Methlyene Blue (MB) solution under a simulated solar light irradiation. The relationship between loading amount and degradation rate was also investigated. It is found that the optimal loading amount of Er3+:YAlO3 is 7 wt%. The recycling test of selected sample was carried out to study the stability of the Er3+:YAlO3 loaded BiPO4 system. The composite materials were finally characterized by field-emission scanning electron microscopy (SEM), X-ray diffraction (XRD) and UV–visible diffuse reflectance spectroscopy (UV–vis DRS). Based on the findings a possible mechanism has been proposed. The existence of luminescence agent (Er3+-doped YAlO3) and the occurrence of upconversion luminescence process have been related with the enhanced photodegradation of MB over composite system.