Sulfur oxides from the combustion of petrol and excessive
emissions
of carbon dioxide (CO2) are currently the main causes of
environmental pollution. Considerable interest has been paid to solving
the challenge, and catalytic reactions seem to be the desired choice.
Due to the high density of Lewis acid active sites, polyoxometalates
are considered to be the ideal choice for these catalytic reactions.
Herein, two captivating polyoxometalate-based metal–organic
complexes, formulated as [Co(H2O)2DABT]2[CrMo6(OH)5O19] ({Co-CrMo
6
}) and [Zn(H2O)2DABT]2[CrMo6(OH)5O19] ({Zn-CrMo
6
})
(DABT = 3,3′-diamino-5,5′-bis(1H-1,2,4-triazole))
were successfully obtained under hydrothermal conditions. The structural
analysis demonstrates that {Co-CrMo
6
} and {Zn-CrMo
6
} are isostructural with two different transition
metal (Co/Zn) ions based on quadridentate Anderson-type [CrMo6(OH)5O19]4– polyanions.
A fan-shaped unit of {Co-CrMo
6
}/{Zn-CrMo
6
} is linked to generate a one-dimensional (1D) ladder-like
structure. Intriguingly, benefitting from rich Co centers with a suitable
energy band structure, {Co-CrMo
6
} displays better photocatalytic activity than {Zn-CrMo
6
} for converting
CO2 into CO, endowing the CO formation of 1935.3 μmol
g–1 h–1 with high selectivity.
Meanwhile, {Co-CrMo
6
} also exhibits a satisfactory removal rate of 99% for oxidizing dibenzothiophene
at 50 °C, which suggests that {Co-CrMo
6
} may be utilized as a potential dual
functional material with immense prospects in photocatalytic CO2 reduction and sulfur oxidation for the first time.