Facile Synthesis of NaYF4:Yb,Tm@TiO2 Core-Shell Structured Composite with Enhanced Photocatalytic Activity for Degradation of RhB Dye

It is an effective method to explore the full spectrum responsive photocatalysts for enhancing their photocatalytic activity. Herein, we have combined the upconversion phosphor with semiconductor to design the full-spectrum light responsive photocatalyst. A facile approach has been developed for synthesis of NaYF4:Yb,Tm@TiO2 core-shell structured composite. The morphologies, crystal phases, chemical compositions, optical performance, and photoelectric properties were characterized. Based on SEM and TEM observation, the formation mechanism of NaYF4:Yb,Tm@TiO2 composite was discussed in detail. The results of photodegradation experiment showed that 22% of Rhodamine B dye in the solution was photodegradated by NaYF4:Yb,Tm@TiO2 composite under NIR light irradiation within 150 min, suggesting that the NaYF4:Yb,Tm@TiO2 core-shell structured composite displayed photocatalytic activity under NIR light irradiation. Furthermore, the photocatalytic ability of NaYF4:Yb,Tm@TiO2 is obvious superior to that of TiO2 under the full-spectrum light irradiation.