In this paper, for the hydrogen abstraction reaction of HCHO by OH radicals assisted by water, formic acid, or sulfur acid, the possible reaction mechanisms and kinetics have been investigated theoretically using quantum chemistry methods and transition-state theory. The potential energy surfaces calculated at the CCSD(T)/6-311++G(df,pd)//MP2(full)/6-311++G(df,pd) levels of theory reveal that, due to the formation of strong hydrogen bond(s), the relative energies of the transition states involving catalyst are significantly reduced compared to that reaction without catalyst. However, the kinetics calculations show that the rate constants are smaller by about 3, 9, or 10 orders of magnitude for water, formic acid, or sulfur acid assisted reactions than that uncatalyzed reaction, respectively. Consequently, none of the water, formic acid, or sulfur acid can accelerate the title reaction in the atmosphere.

CH 4 storage associated with adsorbed natural gas technology attracts considerable researches on finding porous materials with remarkable CH 4 delivery performance. In this work, we update the online accessible computation-ready, experimental (CoRE) covalent organic frameworks (COFs) database with 280 COFs in 12 topologies. All framework structures are constructed and compiled from the respective experimental studies and are further evaluated for CH 4 delivery. The highest deliverable capacity (DC) between 65 and 5.8 bar among the CoRE COFs is 190 v(STP)/v at 298 K achieved by 3D PI-COF-4. Structure−property relationships show that large volumetric surface area generally benefits CH 4 delivery. 2D-COFs can also be top performing materials if constructing their pore channels is passable in three dimensions, as the volumetric surface area will be increased accordingly. This idea can be realized by enlarging the interlayer spacings of 2D-COFs. We also evaluate the DC of CoRE COFs under conditions of 233 K, 65 bar (storage) and 358 K, 5.8 bar (discharge). The highest DC obtained from the CoRE COFs and the designed 2D-COFs are 314 and 337 v(STP)/v, respectively.

In this work, we reported a facile one-pot approach to construct polyhedral oligomeric silsesquioxane (POSS) and imidazolium-based ionic porous hypercrosslinked polymers (denoted iPHCPs) with multiple active sites towards efficient catalytic...

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