Abstract：
Micro- and nanoscale information on the activating and deactivating coking behaviour of zeolite catalyst materials increases our current understanding of many industrially applied processes, such as the methanol-to-hydrocarbon (MTH) reaction. Atom probe tomography (APT) was used to reveal the link between framework and coke elemental distributions in 3D with sub-nanometre resolution. APT revealed 10-20 nanometre-sized Al-rich regions and short-range ordering (within nanometres) between Al atoms. With confocal fluorescence microscopy, it was found that the morphology of the zeolite crystal as well as the secondary mesoporous structures have a great effect on the microscale coke distribution throughout individual zeolite crystals over time. Additionally, a nanoscale heterogeneous distribution of carbon as residue from the MTH reaction was determined with carbon-rich areas of tens of nanometres within the zeolite crystals. Lastly, a short length-scale affinity between C and Al atoms, as revealed by APT, indicates the formation of carbon-containing molecules next to the acidic sites in the zeolite.
摘要：
关于沸石催化剂材料的活化和失活焦化行为的微米级和纳米级信息增加了我们目前对许多工业应用工艺的理解。例如甲醇到烃(MTH)反应。原子探针层析成像（APT）用于以亚纳米分辨率在3D中揭示骨架与焦炭元素分布之间的联系。APT揭示了10-20纳米大小的富铝区域和铝原子间的短程有序(在纳米内)。用共焦荧光显微镜，已发现，沸石晶体的形态以及次级介孔结构对整个单个沸石晶体随时间的微观焦炭分布有很大影响。此外,在沸石晶体内具有数十纳米的富碳区域的情况下，确定了作为MTH反应残留物的碳的纳米级异质分布。最后,C和Al原子之间的短长度尺度亲和力，正如APT所揭示的，表示在沸石中的酸性位点附近形成含碳分子。
