Computational screening‐aided design of transition metal‐doped CeO <sub>2</sub> as NH <sub>3</sub> ‐SCR catalysts
Boyu Wu, Zhuoshen Huang, Danfeng Zhao, Fei-Long Hu, Baoxiang Peng, Ning Pu, Shengen Zhang, Xiubing Huang
Abstract
Abstract Transition metal‐doped CeO 2 catalysts exhibit great potentials for the selective catalytic reduction (SCR) of nitrogen oxide (NO x ) with NH 3 (NH 3 ‐SCR). However, traditional research mainly relies on a lot of experiments to find out effective catalysts, which wastes a lot of time and resources. Screening out effective CeO 2 ‐based catalysts for low‐temperature NH 3 ‐SCR via density functional theory (DFT) calculations is crucial for the rational design and synthesis of efficient catalysts. Herein, transition metal (M = Co, Cr, Cu, Fe, Mn, Mo, Nb, Ni, Ta, Ti, V, and W)‐doped CeO 2 catalysts were screened out via accelerated DFT calculations for NH 3 ‐SCR of nitric‐oxide (NO) using three theoretical terms; (i) an adsorption energy of NH 3 , (ii) an adsorption energy of NO, and (iii) the reaction energies between NO with O 2 and lattice oxygen. The theoretically predicted trend in catalytic performance is as follows: CeO 2 ‐Mn, ‐Cu, ‐Mo > CeO 2 ‐Fe, ‐Co, ‐Ni, ‐V, ‐Cr > CeO 2 ‐W, ‐Ti > CeO 2 ‐Nb, ‐Ta. The theoretical prediction was well verified via experimental NH 3 ‐SCR activity of NO at low temperatures (90–300 °C), demonstrating CeO 2 ‐Mo as efficient NH 3 ‐SCR catalyst across a broad temperature range. Temperature‐programmed desorption of NH 3 and in situ diffuse reflectance infrared Fourier transforms spectroscopy further indicated that metal doping significantly enhanced the NH 3 adsorption capacity and strength of CeO 2 in the medium‐ to low‐temperature range. Consequently, accelerated DFT calculations provide a useful tool with great potentials for predicting the catalytic performance.