Direct Z-scheme charge separation mechanism and photocatalytic properties of (BiO)2CO3-BiOCl composites prepared in-situ

In this work, (BiO)(2)CO3-BiOCl heterojunctions were in-situ constructed by acid etching of (BiO)(2)CO3 using HCl. The formation of (BiO)(2)CO3-BiOCl heterojunctions was confirmed by XRD and high-resolution transmission electron microscopy (HRTEM). The separation properties of photoinduced e(-)/h(+) pairs were investigated by surface photovoltage spectroscopy (SPS). The results show that O-center dot(2)- and (OH)-O-center dot were yielded in the (BiO)(2)CO3-BiOCl composite photocatalytic system. The photocatalytic abilities of the samples toward degradation of methyl orange (MO) were evaluated, the results exhibit that when the molar ratio of (BiO)(2)CO3/BiOCl is 1/8, the sample displays the highest activity. A direct Z-scheme mechanism was proposed.