Self-assembly and photocatalytic properties of three nanosized polyoxometalates based on the {SiNb3W9O40} cluster and transition-metal cations

Three nanoscale Nb/W mixed-addendum polyoxometalates, Cs14K4[(Si4W36Nb12O156)Cu(H2O)2]·47H2O, Cs10K8[(Si4W36Nb12O156)Zn(H2O)2]·28H2O, and Cs16[(H2Si4W36Nb12O156)Cd(H2O)2]·75H2O involving [SiNb3W9O40]7− fundamental building unit, have been synthesized, which all show photocatalytic hydrogen evolution activities. Furthermore, molecules 1, 2, and 3 are stable in the photocatalytic hydrogen evolution system. The embedding transition-metal cations into Nb/W mixed-addendum POMs can improve the photocatalytic H2 evolution activity.