Enhanced photocatalytic treatment of Cr(VI) and phenol by monoclinic BiVO4 with {010}-orientation growth

Abstract

Photocatalytic technology has unique advantages in the purification of organic wastewater containing chromium(VI). Simultaneously photodegradation efficiency of Cr(VI) and phenol was significantly enhanced over BiVO4 with {010}-oriented growth. In this study, the effect of pH values in photoreduction of Cr(VI) and concentrations of phenol in the simultaneous photocatalytic reaction process were systematically analyzed based on characterizations about material physical properties. The results suggested that the enhanced photocatalytic activity over {010}-oriented BiVO4 was attributed to sufficient utilization of surface junction between {010} and {110}. These junctions achieved higher separation efficiency and selectively transfer of photogenerated charge carriers between two surfaces. Thus the photoreduction of Cr(VI) and photooxidation of phenol can selectively occur on the different crystal surfaces. This study demonstrates the possibility of purification of organic wastewater containing toxic heavy metals such as Cr(VI) using photocatalytic technology and provides new ideas and methods for the design of highly active photocatalytic materials.