Li Peng, Li Zhifang, Cui Jinxing, Geng Cui, Kang Yan, Zhang Chao, Yang Changlong
College of Chemistry and Chemical Engineering, Qiqihar University Qiqihar 161006 Heilongjiang China
College of Materials Science and Engineering, Qiqihar University Qiqihar 161006 Heilongjiang China.
RSC Adv. 2019 May 21;9(28):15791-15797. doi: 10.1039/c9ra02456e. eCollection 2019 May 20.
In this paper, CoFeO/graphene catalysts and N-doped graphene/CoFeO (CoFeO/graphene-) catalysts were prepared using the hydrothermal crystallization method for the selective catalytic reduction of NO by NH. The results of the test showed that CoFeO/graphene catalysts exhibited the best denitrification activity when the loading was at 4% and the conversion rate of NO reached 99% at 250-300 °C. CoFeO/graphene- catalysts presented a better denitrification activity at low temperature than CoFeO/graphene catalysts, and the conversion rate of NO reached more than 95% at 200-300 °C. The intrinsic mechanism of CoFeO/graphene- catalysts in promoting SCR activity was preliminarily explored. The physicochemical properties of the samples were characterized using XRD, TEM, N adsorption, XPS, NH-TPD, and H-TPR. The results indicated that nitrogen doping can improve the dispersion of CoFeO, and it also increased the acidic sites and the redox performance conducive to improving the denitrification activity of the catalysts. In addition, CoFeO/graphene- catalysts demonstrated a better resistance to water and sulfur than CoFeO/graphene catalysts.
本文采用水热结晶法制备了CoFeO/石墨烯催化剂和氮掺杂石墨烯/CoFeO（CoFeO/石墨烯-）催化剂，用于NH对NO的选择性催化还原。测试结果表明，当负载量为4%时，CoFeO/石墨烯催化剂表现出最佳的脱硝活性，在250-300℃时NO转化率达到99%。CoFeO/石墨烯-催化剂在低温下比CoFeO/石墨烯催化剂具有更好的脱硝活性，在200-300℃时NO转化率达到95%以上。初步探讨了CoFeO/石墨烯-催化剂促进SCR活性的内在机理。采用XRD、TEM、N吸附、XPS、NH-TPD和H-TPR对样品的物理化学性质进行了表征。结果表明，氮掺杂可以提高CoFeO的分散性，还增加了酸性位点和氧化还原性能，有利于提高催化剂的脱硝活性。此外，CoFeO/石墨烯-催化剂比CoFeO/石墨烯催化剂表现出更好的抗水和抗硫性能。
