Design of Prussian blue analogue-derived double-cone structure Ce–Fe catalysts and their enhanced performance for the selective catalytic reduction of NOx with NH3

Abstract

Prussian blue (PB) and its analogues (PBA) with different structures and adjustable compositions have been recognized as promising materials for catalysis, energy storage, and biological applications. Herein, a simple surface anchoring strategy is proposed to achieve the uniform deposition of CeO₂ nanocrystals on the double-cone structure surface of PBA (denoted as Ce@Ce–Fe catalyst) for the selective catalytic reduction of NO_x with NH₃ (NH₃-SCR). Compared with Ce–Fe and Ce@CeO₂–Fe₂O₃, the Ce@Ce–Fe catalyst exhibited the best catalytic activity, widest working temperature window, and highest SO₂ tolerance, implying its good application in the process of NH₃-SCR. Moreover, the catalysts were characterized systematically to elucidate their surface properties and morphological structure. Taking advantage of the excellent redox performance, unique morphology, mesoporous structure with large surface area and pore diameter, and greater acid content, the Ce@Ce–Fe catalyst exhibited a higher NO_x performance. In addition, the Ce@Ce–Fe catalyst also exhibited significant resistance to H₂O and SO₂ due to its higher content of Fe atoms, implying that Fe plays a critical role in this Ce–Fe based catalytic system. More importantly, the present study indicates that well-dispersed active components and unique architectures can effectively enhance the performance of catalysts.