Synthesis, Structure, Oxygen Evolution Reaction (OER) and Visible - light Assisted Organic Reaction Studies on A2M2TeB2O10 (A = Ba, Pb; M = Mg, Zn, Co, Ni, Cu, Fe)

Abstract

Compounds with the general formula A2M2TeB2O10 (A = Ba, Pb; M = Mg, Zn, Co, Ni, Cu, Fe) have been prepared by solid state techniques and characterised. The structure has M2B2O10 layers connecteyd by TeO6 octahedra giving rise to a three dimensional structure with voids where the Ba2+ ions reside. Substitution of transition elements (M = Co, Ni, Cu) in place of Mg in Ba2Mg2TeB2O10 and (Ba0.5Pb1.5)Mg2TeB2O10 gives rise to interesting colored compounds. The NIR reflectivity studies indicated that the white-colored compounds exhibiting good NIR reflectivity that is comparable to TiO2. The dielectric studies indicated reasonable values with low dielectric loss at low frequencies. The cobalt substituted compounds Ba2(MgCo)TeB2O10 and (Ba0.5Pb1.5)(MgCo)TeB2O10 were explored towards oxygen evolution reaction (OER) in alkaline medium. The compound (Ba0.5Pb1.5)(MgCo)TeB2O10 was found to a good electrocatalyst for OER reaction with faradaic efficiency of ∼ 96%. The Cu-substituted compound, Ba2(Mg1.5Cu0.5)TeB2O10 was found to be a good photocatalyst for the formation of α-chloroketones under visible light in the presence of molecular oxygen.