Covalent combination of polyoxometalate and graphitic carbon nitride for light-driven hydrogen peroxide production

The polyoxometalate (POM) cluster of [PW11O39](7-) (PW11) has been successfully covalent combined with the three dimensionally ordered macroporous graphitic carbon nitride (3DOM g-C3N4) through the organic linker strategy. The characterization such as solid-state NMR and XPS results confirm the organosilicon agent of (triethoxysilyl)-propyl isocyanate can act as the linker to covalent combine the PW11 cluster with 3DOM g-C3N4. The hybrid catalyst of 3DOM g-C3N4-PW11 exhibits efficient catalytic performance (2.4 mu mol h(-1)) for light-driven H2O2 production from H2O and O-2 in the absence of organic electron donors. The ESR results suggest that one-electron reduction of O-2 to center dot OOH is indeed suppressed over 3DOM g-C3N4-PW11. Furthermore, the Koutecky-Levich plot obtained from electrochemical rotating disk electrode (RDE) analysis of oxygen reduction reaction (ORR) for 3DOM g-C3N4-PW11 reveals the value of electron transfer during the ORR process is 2.30, indicating the covalent combination can promote the two-electron O-2 reduction. In addition, the recycle experiment results reveal that the heterogeneous 3DOM g-C3N4-PW11 is catalytic stable.