Facile Preparation of Semiconductor Silver Phosphate Loaded on Multi-walled Carbon Nanotube Surface and Its Enhanced Catalytic Performance

A series of colloidal Ag 3 PO 4 sphere loaded onto multi-walled carbon nanotube (CAPS-MWCNT) photocatalysts containing different mass ratio of MWCNT for the removal of RhB and phenol from waste water were synthesized. The photocatalysts were characterized by X-ray diffraction, UV–Vis diffuse reflectance spectroscopy, thermogravimetry, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy. By SEM and TEM test, the obtained Ag 3 PO 4 form precipitated and colloidal method present different structure morphology and this showed an important effect on the photocatalytic activity. The CAPS-MWCNT photocatalysts were applied to the removal of Rhodamine B (RhB) and phenol from waste water; and the results indicated that CAPS-MWCNT sample can exhibit the high adsorption and photodegradation efficiency under visible light irradiation. For RhB, the removal efficiency of CAPS-MWCNT-4 reaches 99.8% within 50 min, of which adsorption efficiency is 76.5% within the former 30 min; for phenol, the removal efficiency of CAPS-MWCNT-4 reaches 90.6% within 110 min, of which adsorption efficiency is 14.2% within the former 30 min. The experiment results show that CAPS-MWCNT-4 has the highest removal efficiency for RhB while it presents an excellent reusability for removing phenol from waste water. The present work illustrates a new train for the design and synthesis of stable and high efficiency catalysts, applicable for the removal of various organic pollutants by adsorption and photodegradation.