A series of cerium phosphate catalysts with different crystal phases were synthesized by hydrothermal method and co-precipitation method. Hexagonal cerium phosphate (CePO₄-H) shows better NH₃-SCR denitration activity than monoclinic cerium phosphate (CePO₄-M) and mixed phases of CePO₄-H and CePO₄-M. Moreover, CePO₄-H also exhibits excellent activity stability with stream time and cycling stability. Various characterizations were carried out to explain the effects of different crystal phases of CePO₄ on the activity. Among these catalysts, CePO₄-H has much stronger surface acidity that is conducive to the adsorption and activation of NH₃, and more surface adsorbed oxygen species that can effectively improve SCR activity. In situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) were performed to investigate the adsorption and reaction of NH₃ and NO_x on CePO₄-H and CePO₄-M, and the results suggest that the better activity over CePO₄-H follows mainly the Eley–Rideal mechanism in the activity temperature window (300–500 °C) with 100% NO conversion.

采用水热法和共沉淀法合成了一系列不同晶相的磷酸铈催化剂。六方磷酸铈(CePO _{4 -H)显示出比单斜磷酸铈(CePO 4 -M)和CePO 4} -H和CePO ₄ -M混合相更好的NH ₃ -SCR脱硝活性。此外，CePO ₄ -H 还表现出优异的活性稳定性，流时间和循环稳定性。进行了各种表征来解释不同晶相的 CePO ₄对活性的影响。在这些催化剂中，CePO ₄-H的表面酸性更强，有利于NH ₃的吸附和活化，表面吸附的氧种类更多，可以有效提高SCR活性。采用原位 漫反射红外傅里叶变换光谱 (DRIFTS) 研究了 NH ₃和 NO _x在 CePO ₄ -H 和 CePO ₄ -M 上的吸附和反应，结果表明比 CePO ₄ -H 更好的活性如下主要是活动温度窗口（300-500°C）中的 Eley-Rideal 机制，NO 转化率为 100%。