Post-synthetic atomically precise single-Cu II sites in a thiacalix[4]arene-supported octahedral Na@Co 24 cluster: the Cu-Co synergistic effect for selective photocatalytic conversion of CO 2 to CO.

A thiacalix[4]arene-supported octahedral Na@Co 24 cluster has been fabricated by the modular assembly of six Co 4 -(TC4A) polynuclear secondary building units (PSBUs) and eight 2,4,6-PTC linkers. The post-modification of Na@Co 24 by ion exchange of Na + with Cu 2+ on the surface of the octahedron afforded a structurally well-defined Cu@Co 24 cluster. The obtained Cu@Co 24 cluster achieved improved visible-light absorption and selective photoreduction of CO 2 to CO due to the Cu-Co synergistic effect.