| Autor: |
Ahmed, Alauddin, Seth, Saona, Purewal, Justin, Wong-Foy, Antek G., Veenstra, Mike, Matzger, Adam J., Siegel, Donald J. |
| Zdroj: |
Nature Communications; 4/5/2019, Vol. 10 Issue 1, pN.PAG-N.PAG, 1p |
| Abstrakt: |
Few hydrogen adsorbents balance high usable volumetric and gravimetric capacities. Although metal-organic frameworks (MOFs) have recently demonstrated progress in closing this gap, the large number of MOFs has hindered the identification of optimal materials. Here, a systematic assessment of published databases of real and hypothetical MOFs is presented. Nearly 500,000 compounds were screened computationally, and the most promising were assessed experimentally. Three MOFs with capacities surpassing that of IRMOF-20, the record-holder for balanced hydrogen capacity, are demonstrated: SNU-70, UMCM-9, and PCN-610/NU-100. Analysis of trends reveals the existence of a volumetric ceiling at ∼40 g H2 L−1. Surpassing this ceiling is proposed as a new capacity target for hydrogen adsorbents. Counter to earlier studies of total hydrogen uptake in MOFs, usable capacities in the highest-capacity materials are negatively correlated with density and volumetric surface area. Instead, capacity is maximized by increasing gravimetric surface area and porosity. This suggests that property/performance trends for total capacities may not translate to usable capacities. Considering the large number of existing synthesised and hypothesised metal-organic frameworks, determining which materials perform best for given applications remains a challenge. Here, the authors screen the usable hydrogen uptake capacities of nearly 500,000 MOFs, and find that three frameworks outperform the current record-holder. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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