当前位置: X-MOL 学术Chin. J. Catal. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Investigation of lattice capacity effect on Cu2+-doped SnO2 solid solution catalysts to promote reaction performance toward NO -SCR with NH3
Chinese Journal of Catalysis ( IF 16.5 ) Pub Date : 2020-05-01 , DOI: 10.1016/s1872-2067(20)63532-x
Xianglan Xu , Yunyan Tong , Jingyan Zhang , Xiuzhong Fang , Junwei Xu , Fuyan Liu , Jianjun Liu , Wei Zhong , Olga E. Lebedeva , Xiang Wang

Abstract To understand the effect of the doping amount of Cu2+ on the structure and reactivity of SnO2 in NOx-SCR with NH3, a series of Sn-Cu-O binary oxide catalysts with different Sn/Cu ratios have been prepared and thoroughly characterized. Using the XRD extrapolation method, the SnO2 lattice capacity for Cu2+ cations is determined at 0.10 g CuO per g of SnO2, equaling a Sn/Cu molar ratio of 84/16. Therefore, in a tetragonal rutile SnO2 lattice, only a maximum of 16% of the Sn4+ cations can be replaced by Cu2+ to form a stable solid solution structure. If the Cu content is higher, CuO will form on the catalyst surface, which has a negative effect on the reaction performance. For samples in a pure solid solution phase, the number of surface defects increase with increasing Cu content until it reaches the lattice capacity, as confirmed by Raman spectroscopy. As a result, the amounts of both active oxygen species and acidic sites on the surface, which critically determine the reaction performance, also increase and reach the maximum level for the catalyst with a Cu content close to the lattice capacity. A distinct lattice capacity threshold effect on the structure and reactivity of Sn-Cu binary oxide catalysts has been observed. A Sn-Cu catalyst with the best reaction performance can be obtained by doping the SnO2 matrix with the lattice capacity amount of Cu2+.

中文翻译:

研究 Cu2+ 掺杂 SnO2 固溶体催化剂的晶格容量效应以提高对 NO -SCR 与 NH3 的反应性能

摘要 为了解Cu2+的掺杂量对NOx-SCR与NH3反应中SnO2的结构和反应活性的影响,制备了一系列具有不同Sn/Cu比的Sn-Cu-O二元氧化物催化剂并对其进行了充分表征。使用 XRD 外推法,Cu2+ 阳离子的 SnO2 晶格容量确定为 0.10 g CuO/g SnO2,等于 84/16 的 Sn/Cu 摩尔比。因此,在四方金红石 SnO2 晶格中,最多只有 16% 的 Sn4+ 阳离子可以被 Cu2+ 取代以形成稳定的固溶体结构。如果Cu含量较高,催化剂表面会形成CuO,对反应性能产生负面影响。对于纯固溶体相的样品,表面缺陷的数量随着 Cu 含量的增加而增加,直到达到晶格容量,经拉曼光谱证实。结果,表面上的活性氧物质和酸性位点的量(它们对反应性能至关重要)也增加并达到具有接近晶格容量的 Cu 含量的催化剂的最大水平。已经观察到对 Sn-Cu 二元氧化物催化剂的结构和反应性的明显晶格容量阈值效应。通过在SnO2基体中掺杂Cu2+的晶格容量量,可以得到反应性能最好的Sn-Cu催化剂。已经观察到对 Sn-Cu 二元氧化物催化剂的结构和反应性的明显晶格容量阈值效应。通过在SnO2基体中掺杂Cu2+的晶格容量量,可以得到反应性能最好的Sn-Cu催化剂。已经观察到对 Sn-Cu 二元氧化物催化剂的结构和反应性的明显晶格容量阈值效应。通过在SnO2基体中掺杂Cu2+的晶格容量量,可以得到反应性能最好的Sn-Cu催化剂。
更新日期:2020-05-01
down
wechat
bug