Standardization of Methods for Characterizing the Surface Geometry of Solids

Dąbrowski, A.; Robens, E.; Klobes, P.; Meyer, Klas

doi:10.1002/ppsc.200390037

Cited by 9 publications

(4 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Nitrogen adsorption experimental isotherms from 10 −7 to 1 bar and 77 K (sub-critical temperature and pressure) were run on the activated carbons using a Quantachrome Instruments Autosorb-1-C. Nitrogen adsorption allows the characterization of pores in the micropore regime and mesopore regime [15]. Two methods of analysis were performed on the nitrogen isotherms: Brunauer, Emmett, Teller (BET) theory of adsorption [16] and non-local density functional theory (NLDFT) [17].…”

Section: Sample Characterizationmentioning

confidence: 99%

“…As a reference for material properties, BET surface area is useful, but has been shown to be limited for predominantly microporous samples [19]. Non-local density functional theory presents an opportunity to better model gas behavior in micropores [15,20]. This microscopic approach is used to determine isotherms for individual pore sizes and shapes, which are then compared to the experimental isotherm using the integral equation…”

Section: Sample Characterizationmentioning

confidence: 99%

See 1 more Smart Citation

Hydrogen storage in engineered carbon nanospaces

Burress¹,

Kraus²,

Beckner³

et al. 2009

Nanotechnology

View full text Add to dashboard Cite

It is shown how appropriately engineered nanoporous carbons provide materials for reversible hydrogen storage, based on physisorption, with exceptional storage capacities (∼80 g H 2 /kg carbon, ∼50 g H 2 /liter carbon, at 50 bar and 77 K). Nanopores generate high storage capacities (a) by having high surface area to volume ratios, and (b) by hosting deep potential wells through overlapping substrate potentials from opposite pore walls, giving rise to a binding energy nearly twice the binding energy in wide pores. Experimental case studies are presented with surface areas as high as 3100 m 2 g −1 , in which 40% of all surface sites reside in pores of width ∼0.7 nm and binding energy ∼9 kJ mol −1 , and 60% of sites in pores of width >1.0 nm and binding energy ∼5 kJ mol −1 . The findings, including the prevalence of just two distinct binding energies, are in excellent agreement with results from molecular dynamics simulations. It is also shown, from statistical mechanical models, that one can experimentally distinguish between the situation in which molecules do (mobile adsorption) and do not (localized adsorption) move parallel to the surface, how such lateral dynamics affects the hydrogen storage capacity, and how the two situations are controlled by the vibrational frequencies of adsorbed hydrogen molecules parallel and perpendicular to the surface: in the samples presented, adsorption is mobile at 293 K, and localized at 77 K. These findings make a strong case for it being possible to significantly increase hydrogen storage capacities in nanoporous carbons by suitable engineering of the nanopore space.

show abstract

Section: Sample Characterizationmentioning

confidence: 99%

Section: Sample Characterizationmentioning

confidence: 99%

Hydrogen storage in engineered carbon nanospaces

Burress¹,

Kraus²,

Beckner³

et al. 2009

Nanotechnology

View full text Add to dashboard Cite

show abstract

“…Helium displacement within a calibrated vessel [14] at 20 8C was applied using a PYCNOMATIC ATC instrument of Thermo Electron S.p.A., Milano, Italy.…”

Section: Densitymentioning

confidence: 99%

Investigation of surface properties of lunar regolith: Part I

Robens

Bischoff

Schreiber³

et al. 2007

Applied Surface Science

View full text Add to dashboard Cite

“…The mean density of the powders was determined by means of helium displacement within a calibrated vessel (Heiken et al, 1991, Dąbrowski et al, 2003 at 20°C. We used a PYCNOMATIC ATC instrument of Thermo Electron S.p.A., Milano, Italy.…”

Section: Densitymentioning

confidence: 99%

Study on the Possible Existence of Water on the Moon

Robens

Hałas

2009

Geochronometria

Self Cite

View full text Add to dashboard Cite

Abstract:Aim of an extensive research project is an analysis of surface properties of Moon's regolith covering and the assessment of the possible existence of usable water on the Moon. In the present paper a short historical survey on Moon's exploration and recent and planned missions is given. Recent recognitions are discussed on the basis of origin and history of the Moon and the import of water from other celestial bodies. Characteristic data and chemical composition of the Moon's surface are summarised with respect to possible water or ice preservation.Experimental investigations have been made on three typical lunar regolith powder samples from the Apollo 11, 12 and 16 missions. The experiments include spectroscopic and thermal analysis, density measurements and sorptometry. In the present paper we give a survey on measuring methods applied and discuss some results. The measurements confirm results of investigations made with less sensitive equipment shortly after the missions. With regard to water occurrence we found that the regolith cover of the Moon surface is rather hydrophobic and can hardly store water as adsorbed layers.

show abstract

Standardization of Methods for Characterizing the Surface Geometry of Solids

Cited by 9 publications

References 9 publications

Hydrogen storage in engineered carbon nanospaces

Hydrogen storage in engineered carbon nanospaces

Investigation of surface properties of lunar regolith: Part I

Study on the Possible Existence of Water on the Moon

Contact Info

Product

Resources

About