Lacunary polyoxometalates (LPOMs),
a class of anionic metal oxide
clusters, are promising materials as catalysts, photocatalysts, and
electrocatalysts. Designing and functionalizing this type of compound
are key factors for the discovery and development of novel materials.
Herein, a new lacunary polyoxometalate-based compound was designed
as a heterogeneous catalyst, prepared through functionalization of
a lacunary Keggin-type polyoxometalate, i.e., [PMo11O39]7–, with 3-aminopropyltrimethoxysilane
(APTS) and 2-pyridine carboxaldehyde. Subsequent reactions of this
compound with Cu2+ ions led to the desired catalyst, LPMo-Cu.
The catalytic activity of the obtained LPMo-Cu was examined in nitroarene
reduction using sodium borohydride as a reducing agent in aqueous
solution. It was specified that the synthesized LPMo-Cu exhibits high
catalytic efficiency in the reduction of a wide variety of nitroarenes
in a short time (5 min). Furthermore, the stability and recoverability
of the prepared material were proved as a result of four consecutive
reduction cycles without a significant decrease in its efficiency.