Abstract：
The synergistic removal of NOx and chlorinated volatile organic compounds (CVOCs) has become the hot topic in the field of environmental catalysis. However, due to the trade-off effects between catalytic reduction of NOx and catalytic oxidation of CVOCs, it is indispensable to achieve well-matched redox property and acidity. Herein, synergistic catalytic removal of NOx and chlorobenzene (CB, as the model of CVOCs) has been originally demonstrated over a Co-doped SmMn2O5 mullite catalyst. Two kinds of Mn-Mn sites existed in Mn-O-Mn-Mn and Co-O-Mn-Mn sites were constructed, which owned gradient redox ability. It has been demonstrated that the cooperation of different active sites can achieve the balanced redox and acidic property of the SmMn2O5 catalyst. It is interesting that the d band center of Mn-Mn sites in two different sites was decreased by the introduction of Co, which inhibited the nitrate species deposition and significantly improved the N2 selectivity. The Co-O-Mn-Mn sites were beneficial to the oxidation of CB and it cooperates with Mn-O-Mn-Mn to promote the synergistic catalytic performance. This work paves the way for synergistic removal of NOx and CVOCs over cooperative active sites in catalysts.
摘要：
协同脱除NOx和氯化挥发性有机物(CVOCs)已成为环境催化领域的研究热点。然而,由于NOx催化还原和CVOCs催化氧化之间的权衡效应，实现良好匹配的氧化还原性能和酸度是必不可少的。在这里，协同催化去除NOx和氯苯(CB，作为CVOCs的模型）最初已在Co掺杂的SmMn2O5莫来石催化剂上得到证明。构建了Mn-O-Mn-Mn和Co-O-Mn-Mn两种Mn-Mn位点,具有梯度氧化还原能力。已经证明，不同活性位点的合作可以实现SmMn2O5催化剂的平衡氧化还原和酸性。有趣的是，在两个不同位置的Mn-Mn位点的d带中心通过引入Co而降低，这抑制了硝酸盐的沉积并显着提高了N2的选择性。Co-O-Mn-Mn位点有利于CB的氧化，并与Mn-O-Mn-Mn协同作用，促进协同催化性能。这项工作为在催化剂中协同活性位点上协同去除NOx和CVOCs铺平了道路。
