Academic Journal

Pore-Structure Investigation of Bimetallic Zeolitic Imidazolate Framework‑8 Films with Varying Co/Zn Nodes Ratio Using Depth Sensitive Positronium Annihilation Lifetime Spectroscopy

التفاصيل البيبلوغرافية
العنوان: Pore-Structure Investigation of Bimetallic Zeolitic Imidazolate Framework‑8 Films with Varying Co/Zn Nodes Ratio Using Depth Sensitive Positronium Annihilation Lifetime Spectroscopy
المؤلفون: Renjith B. Nelliyil, Jaideep Mor, Manoj Thota, Maciej Oskar Liedke, Maik Butterling, Ahmed G. Attallah, Eric Hirschmann, Andreas Wagner, Sandeep Kumar Sharma
سنة النشر: 2024
المجموعة: Smithsonian Institution: Figshare
مصطلحات موضوعية: Biochemistry, Space Science, Environmental Sciences not elsewhere classified, Biological Sciences not elsewhere classified, Chemical Sciences not elsewhere classified, Physical Sciences not elsewhere classified, zeolitic imidazolate frameworks, study also reveals, size selective separation, opening phenomenon occurring, liquid molecules intrusion, enhanced ligand swinging, 200 ° c, 100 ° c, surface energy minimization, near surface region, intercrystalline void size, silicon substrate using, pore sizes corresponding, inherent pore structure, dependent pore structure, highly crystalline bimetallic, intracrystalline pore network, different pores indicates, intercrystalline pore structure, pore structure investigation, bimetallic films due, structure investigation, pore network, intercrystalline voids
الوصف: The gas–framework interaction induced gate-opening phenomenon occurring in zeolitic imidazolate frameworks (ZIFs) has restricted the ability of conventional experimental techniques involving gas or liquid molecules intrusion in ZIFs for determination of their inherent pore structure. The pore structure investigation of ZIF-based membranes/thin films using conventional techniques becomes even more difficult due to the limited amount of material, and the existence of pores that are not connected to the exterior surface. ZIF-based membranes are proposed as an advanced alternative for size selective separation of gases mixtures, which is primarily governed by the intra- and intercrystalline pore structure of these membranes. We present a systematic investigation of the depth-dependent pore structure of highly crystalline bimetallic (Zn/Co) ZIF-8-based films with varying metal ratio deposited on a silicon substrate using a fast current driven synthesis method. Using depth-dependent positronium annihilation lifetime spectroscopy, pore sizes corresponding to the intracrystalline pore network (aperture and central cavity) and intercrystalline voids have been determined. Pore aperture (window for size selective separation) at the near surface region is observed to be constrained compared to the bulk of the films due to surface energy minimization by linker twisting. Co loading in ZIF-8 reduces the aperture and cavity pore sizes due to the comparatively more rigid Co–N bond. The intercrystalline void size of the films is reduced on ∼13.5% Co loading in ZIF-8, which is consistent with the high gas separation selectivity of membranes reported with this loading. Positronium intensity variation corresponding to different pores indicates that pore interconnectivity is reduced in the films with Co loading ∼30–60%. The pore network of bimetallic films is observed to be highly stable up to 200 °C under vacuum annealing, whereas under atmospheric conditions the pore network begins collapsing from 100 °C, which is much earlier than ...
نوع الوثيقة: article in journal/newspaper
اللغة: unknown
Relation: https://figshare.com/articles/journal_contribution/Pore-Structure_Investigation_of_Bimetallic_Zeolitic_Imidazolate_Framework_8_Films_with_Varying_Co_Zn_Nodes_Ratio_Using_Depth_Sensitive_Positronium_Annihilation_Lifetime_Spectroscopy/25109222
DOI: 10.1021/acs.jpcc.3c07257.s001
الاتاحة: https://doi.org/10.1021/acs.jpcc.3c07257.s001
Rights: CC BY-NC 4.0
رقم الانضمام: edsbas.33A5F590
قاعدة البيانات: BASE
الوصف
DOI:10.1021/acs.jpcc.3c07257.s001