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

Abstract

A series of colloidal Ag3PO4 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 Ag3PO4 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.