Low-Temperature Reduction of NO by NH with Unity Conversion on Nanofilament MnO/Activated Semi-Coke Catalyst.

Selective catalytic reduction of nitrogen oxides with NH at low temperatures remains a crucial goal for industrial applications. However, effective catalysts operating at 70-90 °C are rarely reported, limiting SCR scenarios to high-temperature conditions. Herein, we report a unique MnO nanofilament catalyst grown on activated semi-coke synthesized via a one-step in situ hydrothermal approach, which exhibits a stable and marked 100 % conversion rate of NO to N with 100 % selectivity at 90 °C, superior to the other prepared structures (nanowires, nanorods, and nanotubes). Temperature-programmed desorption shows a large number of acid sites on MnO(NFs)/ASC, benefiting the formation of NH ions. Meanwhile, diffuse reflectance infrared Fourier transform spectroscopy reveals the activation of NO with O to form bidentate nitrate/bridging nitrate NO intermediates via bidentate nitrate species, triggering the Fast SCR with NH at low temperatures. Such an effective, easy-to-prepare, and low-cost catalyst paves a new pathway for low-temperature SCR for a wide range of application scenarios.