MnO_x and MoO_x, as additives, have proved effective in enhancing the NH₃ selective catalytic reduction activity of catalysts. In this study, a new Mn–Fe–Mo catalyst was prepared using both the precipitation method and impregnation method. The redox properties, surface acidity, and reaction intermediates of the prepared catalysts were analyzed using various techniques. The test results showed that the MFMo₄ catalyst achieved a NO_x conversion rate exceeding 90% over the temperature range of 120–390 °C, demonstrating high potential to replace V-based catalysts due to outstanding activity at both high and low temperatures. The addition of MoO_x exerted a detrimental impact on the redox property and avoided the production of N₂O, thereby enhancing the N₂ selectivity. Furthermore, the codoping of MnO_x and MoO_x inhibited the adsorption of NO_x on the catalysts while resulting in an increased number of Lewis acid sites on the catalyst. This promoted its reaction via the Eley–Rideal mechanism, which played a crucial role in ensuring the catalyst had excellent SCR activity over a wide temperature range.

中文翻译：

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新型 MnOx-MoOx 共掺杂铁基 NH3-SCR 催化剂，在宽温度范围内具有优异的催化活性

MnO _x和MoO _x作为添加剂已被证明可以有效提高催化剂的NH ₃选择性催化还原活性。本研究采用沉淀法和浸渍法制备了新型Mn-Fe-Mo催化剂。使用各种技术分析所制备的催化剂的氧化还原性质、表面酸性和反应中间体。测试结果表明，MFMo ₄催化剂在120-390℃的温度范围内实现了超过90%的NO _{x转化率，由于在高温和低温下均具有出色的活性，因此具有替代V基催化剂的巨大潜力。 MoO x}的添加对氧化还原性能产生不利影响并避免了N ₂ O的产生，从而提高了N ₂选择性。此外，MnO _x和MoO _x的共掺杂抑制了催化剂上NO _x的吸附，同时导致催化剂上路易斯酸位的数量增加。这通过 Eley-Rideal 机制促进了其反应，这对于确保催化剂在较宽的温度范围内具有优异的 SCR 活性发挥了至关重要的作用。