Low temperature selective catalytic reduction of NOx with NH3 with improved SO2 and water resistance by using N-doped graphene dots-CuO–CeO2 nano-heterostructures modified vanadate catalysts

Abstract

Herein, we report a facile strategy for efficient NH3-SCR catalytic performance of vanadate-based catalysts with superior sulfur and water resistance at low temperature (<200 °C). The catalyst design strategy is based on the selective adsorption of NO2 via the functionalization of N-doped graphene quantum dots (N-GQDs) and fast-SCR via the functionalization of CuO–CeO2 (CuCe) on 4V1W/Ti catalysts. The impregnation of 1 wt% N-GQDs and 2.8 wt% CuCe leads to more surface acid sites and facilitate the strong interaction between Cu-Ce-V oxides, thus improving NOx adsorption and improved redox process in low temperature ranges (180–220 °C). The synthesized CuCe-N-GQD-4V1W/Ti catalyst shows high DeNOx activity over 92 % with excellent N2 selectivity and SO2/H2O resistance at 200 °C. In situ diffuse reflectance Fourier transform analysis confirmed the Eley–Rideal SCR reaction pathway over the CuCe-N-GQDs-4V1W/Ti catalyst.