Photocatalytic behaviors of epitaxial BiVO4 (010) thin films

Photocatalytic studies performed on well-defined epitaxial thin films and heterostructures allow the direct investigation of crystallographic-dependent reactivity, and can provide fundamental insights into the reaction mechanisms. In this work, we show that phase-pure, monoclinic BiVO 4 nanoislands with a truncated pyramid shape with the (010) top surface and {110} sidewalls can be grown on (001)-oriented yttria-stabilized zirconia (YSZ) substrates with an epitaxial relationship of BiVO4(010)[0011 // YSZ(001)[100]. The resulting nanostructures show a strong size-dependent mass-normalized photocatalytic activity, with highly dispersed nanoislands at low coverage being the most active. Pb(NO3)(2) photooxidation or photoreduction reactions can be controlled in aqueous solution with and without adding NaIO3 as a electron scavenger, leading to the selective deposition of PbO2 or Pb on {110} or (010) surfaces of BiVO4, respectively.