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Ammonia is considered a basic building block for fertilizers. Also, it is an economically efficient and technologically suitable solution for energy storage and transportation. Non-thermal plasma-driven catalysis powered by renewable energy is considered as a green alternative to the conventional Haber-Bosch process for ammonia synthesis. The main challenge in this electron-mediated route is the low ammonia synthesis production, given the plasma-induced decomposition of the freshly generated ammonia during the reaction. Herein we report the plasma-assisted ammonia synthesis in a dielectric barrier discharge reactor packed with CC3 crystals, a prototypical porous organic cage, and a molecular-sieve membrane fabricated from the same CC3 material. The CC3 crystals delivered the highest ammonia synthesis rate (0.06 μmol min−1 m−2) compared to other microporous catalysts such as zeolite (SAPO-34) and metal-organic frameworks (ZIF-8, ZIF-67) (below 0.02 μmol min−1 m−2). The CC3 porous cage with well-defined octahedral crystal geometry provides partial protection while the CC3 membrane offers both adsorption and separation effects for the freshly formed ammonia from its in-situ decomposition, securing an excellent ammonia synthesis rate of 20.3 μmol min−1 m−2. The findings from this work unfolds novel insights into rational designs of advanced porous catalyst and membrane for plasma-driven catalytic ammonia synthesis in a sustainable and efficient way.
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Tuning Material Properties of Porous Organic Cage CC3 with Postsynthetic Dynamic Covalent Chemistry
Abstract Porous organic cages (POCs) represent a new class of microporous materials with an impressive breadth of potential applications. One of their many advantages is the degree of tunability of cage properties, similar to that seen in more established microporous materials like metal‐organic frameworks. In this work, a prototypical POC, CC3, is used to explore the potential to tune cage properties via post‐synthetic dynamic covalent chemistry. Ethylenediamine, the linker used in another POC, CC1, was partially substituted into the CC3 cage structure to varying degrees based on the starting relative molar ratios. The resulting products were investigated for the relative distribution of the two linkers, crystallinity, and surface area. It was found that even when small amounts of other compatible diamine linkers are introduced, they substitute into the existing cages, although some structural products are apparently favored over others within the reactant ratios investigated.
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- Award ID(s):
- 1653153
- PAR ID:
- 10364399
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- European Journal of Organic Chemistry
- Volume:
- 2022
- Issue:
- 2
- ISSN:
- 1434-193X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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