Carbon black decorated BiOCl with largely enhanced photocatalytic activity toward removal of RhB

Abstract

In this work, carbon black (CB) decorated BiOCl photocatalysts were successfully synthesized via a hydrothermal approach. The as-fabricated photocatalysts were characterized by various analytical methods. UV–Vis DRS spectra suggest that CB/BiOCl composite photocatalysts hold stronger visible light absorption ability than that of the pure BiOCl. XRD and Raman results confirm that there exists a powerful chemical interaction between BiOCl and CB, which is beneficial to the transfer of the photo-induced electrons to the CB. Surface photovoltage spectroscopy (SPS), photoelectrochemical and electrochemical impedance spectra (EIS) results illustrate that the separation rate of photo-generated charge pairs of CB/BiOCl photocatalysts was significantly boosted. The photocatalytic activities of CB/BiOCl composite photocatalysts were evaluated under simulated sunlight illumination using rhodamine B (RhB) as a target pollutant. The experimental results display that decoration of BiOCl by low loading of CB can largely enhance the photocatalytic activity. The boosted photocatalytic activity is attributable to the high separation rate of photo-generated charge pairs, originating from the electroconductive property of CB and the powerful interaction between BiOCl and CB.