负载型金属单原子催化剂低温去除气态苯

This proposal is to study the complete oxidation of gaseous benzene over catalytically active single metal atoms supported on doped Hollandite-type manganese oxides (HMO) at low temperatures, the objectives of which are to synthesize atomically dispersed metal catalysts and to test their catalytic performance in the low-temperature oxidation of benzene. .The main scientific issues to be solved are as follows: 1) To synthesize HMO with the framework substitution by Cu2+ and the tunnel doping of Ce4+ in order to obtain desired doping amounts and an optimal Cu2+/Ce4+ ratio. 2) To anchor single metal atoms such as Pt, Pd, Au or Ag on the surfaces of the above HMO. 3) To establish the structure-activity relationship and 4) the reaction mechanism of catalytic oxidation of benzene over the single-atom catalysts..There are four expected results: i) The doped HMO with the framework substitution by Cu and the tunnel doping of Ce will be successfully synthesized, and the optimal doping amounts of Cu2+ and Ce4+ and the Cu2+/Ce4+ molar ratio will be obtained. ii) Atomically dispersed metal (Pt, Pd, Au or Ag) catalysts will be successfully synthesized, which show high catalytic performance in the complete oxidation of benzene. iii) The structure-activity relationship in catalytic oxidation of benzene over the single-atom catalysts will be established. iv) The mechanism of the complete oxidation of benzene over the single-atom catalysts will be achieved by combining experimental data with theoretical calculations. This study is of importance to understand the complete oxidation of benzene over the supported metal catalysts at the atomic level, and it is also critical to reveal the nature of the catalytic oxidation of the typical volatile organic compounds such as benzene at low temperatures from the theoretical and practical viewpoints.

本项目为负载型金属单原子催化剂低温去除气态苯，拟合成高活性的掺杂Hollandite型氧化锰（HMO）负载贵金属单原子催化剂和研究其对苯的低温氧化性能。拟解决的科学问题：1）Cu2+和Ce4+分别对HMO的骨架和孔道定位和定量掺杂；2）在掺杂的HMO表面负载Pt、Pd、Au或Ag单原子催化剂的可控合成；3）单原子催化剂结构和对苯催化性能之间关系的建构；4）单原子催化剂上苯氧化反应的机理。预期的重要成果：i）优化出最佳的Cu2+/Ce4+掺杂比，合成定位定量掺杂高活性的HMO；ii）可控合成低温高效去除苯的金属单原子催化剂；iii）建立金属单原子催化剂在苯氧化反应中的结构-活性之间的构效关系；iv）获得金属单原子催化剂上氧化苯的反应机理。本项目对从原子水平理解负载型金属催化剂对苯的氧化性能具有重要的科学意义，对揭示催化低温氧化典型VOCs的一般普适性的规律具有重要的理论和实用价值。

本项目为负载型金属单原子催化剂低温去除气态苯的研究，拟探究负载型金属单原子催化剂对氧的活化和苯的氧化机理，并从原子水平理解金属单原子催化剂的氧化性能，并得出负载型催化剂对以苯为典型代表的挥发性有机污染物(VOCs)氧化的一般普适性的规律。研究成果包括：(i) 载体的筛选：发现具有丰富{001}面的钙锰矿型氧化锰纳米颗粒(HMO NP)在催化苯氧化上比HMO nanorod更具活性，为合理设计高活性过渡金属氧化物催化剂，以有效地在低温下消除苯在内的VOCs提供了策略；(ii) 载体的改性：以Cu掺杂的HMO对一氧化碳（CO）的催化氧化为例，发现Cu离子掺杂进入HMO的骨架后形成的铜锰氧化物催化剂在CO氧化中表现出了优异的性能，降低了表观活化能，其主要原因来源于掺杂铜离子和锰离子前沿轨道之间的强电子相互作用，从而加快了CO氧化和O2还原的氧化还原循环，为研究其他过渡金属混合氧化物催化剂的性能改进提供了一个合理的策略。(iii) 负载型贵金属催化剂对苯的催化研究，以Pt/CeO2对苯的催化氧化为例，发现Pt纳米粒子比单原子负载在CeO2上具有更高的活性，这为研究其他负载型贵金属的催化性能提供了参考。本项目共发表文章15篇，包括2篇Nature Communications (IF = 14.919)，2篇Environmental Science & Technology(IF = 9.028)，3篇Chemical communications (IF = 6.222)，2篇ChemCatChem (IF = 5.686)，1篇Chemistry - A European Journal (IF = 5.236)，1篇Journal of Physical Chemistry C (IF = 4.126)，1篇Journal of Physics and Chemistry of Solids (IF = 3.995)，3篇Industrial & Engineering Chemistry Research (IF = 3.72)。