The effects of chemical and structural surface heterogeneity on the CH4 adsorption behaviour on microporous carbons have been investigated using a hybrid theoretical approach, including the use of density functional theory (DFT), molecular dynamics (MD), and grand canonical Monte Carlo (GCMC) simulations. Bader charge analysis is first performed to analyze the surface atomic partial charges. Th...

Adsorption behavior of unburned carbons from fly ash has been investigated in this study. Batch tests and column test were carried out for several unburned carbon samples from various ash sources and processing schemes. Adsorption isotherms have been obtained from these tests. Results show that the unburned carbons have equal or better adsorption capacity for elemental mercury comparing with so...

Here we present a statistical mechanical lattice model which is exactly solvable using a matrix method and allows treatment of adsorption induced gate opening structural transformations of metal-organic frameworks which are nanoporous materials with exceptional adsorption properties. Modelling of these structural changes presents a serious theoretical challenge when the solid and gas species ar...

Single-molecule trap: Easy activation of the water-stable metal-organic framework PCN-200 provides a new route to low-energy selective CO(2) capture through stimuli-responsive adsorption behavior. This elastic CO(2) trapping effect was confirmed by single-component and binary gas-adsorption isotherms and crystallographic determination.

We investigated the high-density CO adsorption phase formed on a Pt(111) surface when exposed to CO gas of pressure ranging from UHV to 100 mTorr using near-ambient-pressure (NAP)-XPS. Combined results from the NAP-XPS measurements and DFT calculations reveal the adsorption structure of CO molecules in the dense CO overlayer, which is stable under realistic conditions.

We consider the thermodynamics of adsorption of gases in porous solids from both the perspective of absolute properties which appear naturally in theoretical studies and that of excess properties which are measured in experiments. Our thermodynamic description starts by treating the gas (or gas mixture) plus porous solid system as a mixture to which we can apply solution thermodynamics. We show...

ZIF-8, a prototypical zeolitic porous coordination polymer, prepared via the self-assembly of tetrahedral atoms (e.g. Zn and Co) and organic imidazolate linkers, presents large cavities which are interconnected by narrow windows that allow, in principle, molecular sieving. However, ZIF-8 shows flexibility due to the swing of the imidazolate linkers, which results in the adsorption of molecules ...

The present work presents a useful comparison of micropore size distributions (MPSDs) obtained from gas adsorption and image analysis of high-resolution transmission electron micrographs. It is shown that the MPSD obtained for a chemical activated carbon is concordant with that obtained from CO2 adsorption. In addition, this technique has allowed us to obtain the MPSD of a carbon molecular siev...

Aerogels have an extraordinarily large internal surface area which is accessible via open pores, making them candidates for filters and gas adsorption media. The idea is frequently included in lists of potential applications, but little research has been conducted on the use of aerogels as filters or adsorption media. Consideration of aerogels for use as aerosol collection media requires knowle...

Pillar substitution in a long-known metal-organic material with saturated metal centres, [Cu(bipy)(2)(SiF(6))](n), has afforded the first crystallographically characterized porous materials based upon TiF(6)(2-) and SnF(6)(2-) anions as pillars. Gas adsorption studies revealed similar surface areas and adsorption isotherms but enhanced selectivity towards CO(2)vs. CH(4) and N(2).