Co-based MOF heterogeneous catalyst for the efficient degradation of organic dye via peroxymonosulfate activation.

In this study, a new cobalt-based metal-organic framework (JLNU-500), [Co2(OH)(PBA)(AIP)]·3DMA·0.75H2O (4-(pyridin-4-yl) benzoic acid (HPBA), 5-aminoisophthalic acid (H2AIP) and N,N-dimethylacetamide (DMA)), was fabricated using a solvothermal method. JLNU-500 has 3D network architecture with 1D nanopore channels. The prepared JLNU-500 can activate peroxymonosulfate (PMS) for Rhodamine B (RhB) dye decolorization. Interestingly, catalyst JLNU-500 exhibited high efficiency for PMS activation, and nearly 100% (above 99.8%) removal of RhB with a high concentration (50.0 mg L-1, 100 mL) was achieved within 6 min. The reaction rate constant of the JLNU-500/PMS system was 1.02 min-1 calculated based on the pseudo-first-order kinetics, which is higher than that of the other reported catalysts. Furthermore, the factors, which could influence PMS activation were also investigated, such as PMS dosage, catalyst dosage, pollutant RhB concentration, reaction temperature and solution pH. More importantly, the radical trapping experiments ferreted out that sulfate (SO4˙-) and hydroxyl (˙OH) radicals were the dominating oxidants in the removal of RhB. Moreover, the possible degradation mechanism was elucidated. This study provides new prospects for fabricating new MOFs that can potentially be employed for high-efficiency catalytic oxidation as heterogeneous catalysts.

Conjugated microporous polymer networks with adjustable microstructures for high CO2 uptake capacity and selectivity.

A series of phenylene-based conjugated microporous polymers (CMPs) of the A6 + Mx (x = 2, 3, 4, 6) type were synthesized. By tuning the monomer length and geometry, the BET surface area of CMPs can be tuned from 571 to 1115 m2 g-1. Amongst the synthesized CMPs, A6CMP-1 exhibits the highest CO2 adsorption capacity of 1218 mg g-1 at 318 K and 60 bar pressure. In addition, A6CMP-4 shows a high selectivity ratio of 47 for CO2/N2.