Facile Immobilization of a Lewis Acid Polyoxometalate onto Layered Double Hydroxides for Highly Efficient N‐Oxidation of Pyridine‐Based Derivatives and Denitrogenation

N‐Oxides are a class of highly important compounds that are used widely as synthetic intermediates. In this paper, we demonstrate for the first time the use of a polyoxometalate‐based composite material as a highly efficient heterogeneous catalyst for the N‐oxidation of pyridines and its derivatives in the presence of H 2 O 2 at room temperature. The composite was prepared by the intercalation of the [La(PW 11 O 39 ) 2 ] 11− anion into a layered double hydroxide (LDH) modified with tris(hydroxymethyl)aminomethane (Tris). Additionally, the Tris‐LDH‐La(PW 11 ) 2 ‐based catalyst has been employed for the denitrogenation of a model oil mixture in the presence of 1‐butyl‐3‐methylimidazolium tetrafluoroborate and H 2 O 2 . Denitrogenation can be achieved in 40 min at 75 °C. Finally, the heterogeneous catalyst can be recovered easily and reused at least 10 times without a measurable decrease of the catalytic activity and disintegration of the Tris‐LDH‐La(PW 11 ) 2 structure.