Single-Atom Ru-Implanted Metal–Organic Framework/MnO2 for the Highly Selective Oxidation of NOx by Plasma Activation

In an attempt to achieve the selective oxidation of NO x, a hybrid catalyst of single-atom-anchored metal organic frameworks (MOF, NH 2 -UiO-66) and MnO 2 was constructed and used in the plasma catalytic process. Isolated Ru sites were successfully implanted into the structure of the MOF by simply stirring the mixed liquor containing both MOF and RuCl 3, facilitating plasma discharge, NO/NO 2 adsorption, and formation of • OH radicals. A special oxo-bridged Zr 4+ –O–Ru 3+ was constructed to accelerate electron transfer and continuous proceeding of the reaction. Directional migration of generated electrons from MOF to Ru sites was witnessed when MOF was activated by plasma-induced “pseudo-photocatalysis”. The total (100%) selective plasma-catalytic oxidation of NO x to NO 2 – and NO 3 – was achieved at an SIE of 75.3 J/L. The byproduct O 3 was effectively degraded and utilized by MnO 2, facilitating the deep oxidation of NO x . The facile realization of single atoms would be an ideal way to produce MOF-based catalysts with desired performance. Efficiently combining plasma with single atom-decorated MOF catalysts can provide additional prospects for the plasma-catalytic system.