Octamolybdate-Based Metal–Organic Framework with Unsaturated Coordinated Metal Center As Electrocatalyst for Generating Hydrogen from Water

Two octamolybdate-based MOFs with unsaturated coordinated
metal centers formulated as Cu3(Mo8O26)­(H2O)2(OH)2(L1)4 (L1
= 4H-4-amino-1,2,4-triazole) (1) and
Ag4(Mo8O26)­(L2)2.5(H2O) (L2 = 3,5-dimethyl-4-amino-4H-1,2,4-triazole)
(2) were synthesized and structurally characterized by
single-crystal X-ray diffractions. Complex 1 exhibits
a 1D chain-like structure. In complex 2, 1D Ag-octamolybdate
chains in the ac plane are covalently embedded into
the 2D Ag-L2 layer, and the Ag-octamolybdate chains in the bc plane covalently link the 2D layers into 3D architecture.
The two complexes both exhibit electrocatalytic activities toward
generating H2 from water with lowered overpotentials and
enhanced currents, and the Cu complex exhibits better electrocatalytic
activity toward generating H2 from water than the Ag complex.