Polymolybdate-guided assembly of a thiacalix[4]arene-protected Ag nanocluster for electrocatalytic CO2 reduction

Abstract

A large polymolybdate-templated {Ag₄₉Mo₁₆} cluster protected by six thiacalix[4]arene (TC4A) molecules was synthesized by a one-pot solvothermal reaction. Structural analysis shows that the {Ag₄₉Mo₁₆} is assembled by inserting a [Mo₆O₂₂]⁸⁻ cluster into a [Ag₄₉Mo₁₀@(TC4A)₆] cage, representing the first polyoxometalate-templated Ag cluster protected by calixarene macrocyclic ligands. The solution stability and photoelectric properties of {Ag₄₉Mo₁₆} are discussed. Furthermore, this POM-templated Ag nanocluster realized electrocatalytic CO₂ reduction applications, and 44.75% CO faradaic efficiency (FE) was obtained at a voltage of −0.8 V (vs. RHE).