Deng Yulong, Zheng Jiacheng, Chen Wenting, Wang Xu, Deng Chengliao, Cai Xiaoming, Cai Jinming, Tan Honglin
Kunming Univ Sci & Technol, Fac Mat Sci & Engn, Kunming, 650000, Yunnan, P. R. China.
Kunming Univ Sci & Technol, Fac Mech & Elect Engn, Kunming, 650000, Yunnan, P. R. China.
Phys Chem Chem Phys. 2025 Jul 2;27(26):13961-13975. doi: 10.1039/d5cp01422k.
NH selective catalytic reduction (SCR) is a promising method for NO removal, but its low-temperature effectiveness and narrow operating window limit industrial use. This study demonstrates, through DFT calculations and experimental validation, that Fe-doped CoMnO (CoFeMnO) catalysts can effectively enhance catalytic activity. Through the in-depth study of NH-SCR, it was found that the NH adsorption on the catalyst surface might be significantly enhanced by the doping of Fe ( = -1.29 eV → -1.42 eV), and it was also further demonstrated that the NH had a better adsorption energy on the surface of the CoFeMnO catalyst through the electron difference density (EDD) and partial density of states (PDOS). In addition to this, the CoFeMnO catalyst not only reduces the first step of the dehydrogenation reaction of NH ( = 0.86 eV → 0.83 eV), but also lowers the energy barrier of the NH-SCR ( = 1.11 eV → 0.86 eV). All these calculations demonstrate that Fe doping has the potential to significantly enhance catalytic performance. CoMnO and Fe-doped CoMnO (CoFeMnO) catalysts were synthesized using sol-gel and impregnation techniques, respectively. Through characterization and performance testing, CoFeMnO is found to exhibit a more efficient NO conversion (87% at 250 °C), and its N selectivity is also slightly improved (64%), which matches with the calculation results. In this study, a method to improve the denitrification efficiency of CoMnO spinel catalysts was proposed, which provides a new idea for the development of CoMnO catalysts.
氨选择性催化还原（SCR）是一种很有前景的脱硝方法，但其低温效率和狭窄的操作窗口限制了工业应用。本研究通过密度泛函理论（DFT）计算和实验验证表明，铁掺杂的钴锰氧化物（CoFeMnO）催化剂可以有效提高催化活性。通过对氨选择性催化还原的深入研究发现，铁的掺杂可能会显著增强氨在催化剂表面的吸附（从-1.29 eV提高到-1.42 eV），并且通过电子密度差（EDD）和态密度（PDOS）进一步证明了氨在CoFeMnO催化剂表面具有更好的吸附能。除此之外，CoFeMnO催化剂不仅降低了氨脱氢反应第一步的反应能（从0.86 eV降至0.83 eV），还降低了氨选择性催化还原反应的能垒（从1.11 eV降至0.86 eV）。所有这些计算表明，铁掺杂具有显著提高催化性能的潜力。分别采用溶胶-凝胶法和浸渍法合成了CoMnO和铁掺杂的CoMnO（CoFeMnO）催化剂。通过表征和性能测试发现，CoFeMnO表现出更高的NO转化率（250℃时为87%），其N选择性也略有提高（64%），这与计算结果相符。本研究提出了一种提高CoMnO尖晶石催化剂脱硝效率的方法，为CoMnO催化剂的开发提供了新思路。
