Vanadium in strongly correlated electron system Ni_1-xV_xWO₄: Paradoxically boosted deNO_x reaction under SO_x environment via modulating electron correlation

The persistent challenge of NO_x selective catalytic reduction degradation in the presence of SO_x has remained unresolved for decades. In this study, we report a paradoxical boosted denitration performance more than 20% under the SO_x environment through controlling the charge state of V utilizing strongly correlated electron systems (SCES) in Ni_1−xV_xWO₄. Substitutional doped V at the Ni site, and the computed charge gap from DFT confirms the SCES. Through the manipulation of the strong correlation between V and Ni, V preserves the between + 2–3 charge state in the presence of SO_x. Furthermore, we achieved a stable oxidation/reduction cycle and higher denitration efficiency by altering the oxidation point of (NH₄)HSO₄-contaminated Ni_1−xV_xWO₄. This results from deliberate decrease in Coulombic repulsion between Ni and V, improving electron transfer for catalytic performance. This revelation offers a resolution of exceptional denitration performance within SO_x in industrial exhaust systems, exploiting the foundational principles of SCES.