A sandwiched Co4-added polyoxometalate for efficient visible light-driven hydrogen evolution

A novel Co 4 -added polyoxometalate Cs 4 [(Co(H 2 O) 5 ) 2 {(μ 2 -Co(H 2 O) 4 ) 2 Co 4 (H 2 O) 2 (B-α-GeW 9 O 34 ) 2 }]·6H 2 O has been made by a lacunary directing strategy, showing high activity with an H 2 evolution rate of 1485.95 μmol h −1 g −1 with good catalytic stability.