Roles of Bi, M and VO4 tetrahedron in photocatalytic properties of novel Bi0.5M0.5VO4 (M=La, Eu, Sm and Y) solid solutions for overall water splitting

► BMV solid solutions were novel highly efficient V-based photocatalysts for overall water splitting. ► Photocatalytic activity of BMV solid solution related to the effective ionic radii of M cations. ► Incorporation of Bi is one of key factors for the highly efficient activity of BMV solid solution. ► Incorporation of Y is dispensable for H2 production.