Publications
Oschatz, Martin | Borchardt, Lars | Thommes, Matthias | Cychosz, Katie A. | Senkovska, Irena | Klein, Nicole | Frind, Robert | Leistner, Matthias | Presser, Volker | Gogotsi, Yury | Kaskel, Stefan
DOI:
Sierpinski carbon: Macroporous carbide-derived carbon monoliths (DUT-38) were synthesized starting from SiC-PolyHIPEs, resulting in a hierarchical micro-, meso-, and macroporous structure. The high specific surface area and high macropore volume renders PolyHIPE-CDC an excellent adsorbent combining high storage capacity with excellent adsorption rates in gas storage and air filtration.
Oschatz, Martin | Borchardt, Lars | Thommes, Matthias | Cychosz, Katie A. | Senkovska, Irena | Klein, Nicole | Frind, Robert | Leistner, Matthias | Presser, Volker | Gogotsi, Yury | Kaskel, Stefan
DOI:
DOI:Presser, Volker | Yeon, Sun-Hwa | Vakifahmetoglu, Cekdar | Howell, Carol A. | Sandeman, Susan R. | Colombo, Paolo | Mikhalovsky, Sergey | Gogotsi, Yury
DOI:
DOI:Zhou, Hua | Rouha, Michael | Feng, Guang | Lee, Sang Soo | Docherty, Hugh | Fenter, Paul | Cummings, Peter T. | Fulvio, Pasquale F. | Dai, Sheng | McDonough, John K. | Presser, Volker | Gogotsi, Yury
DOI:
The nanoscale interactions of room temperature ionic liquids (RTILs) at uncharged (graphene) and charged (muscovite mica) solid surfaces were evaluated with high resolution X-ray interface scattering and fully atomistic molecular dynamics simulations. At uncharged graphene surfaces, the imidazolium-based RTIL ([bmim+][Tf2N-]) exhibits a mixed cation/anion layering with a strong interfacial densification of the first RTIL layer. The first layer density observed via experiment is larger than that predicted by simulation and the apparent discrepancy can be understood with the inclusion of, dominantly, image charge and π-stacking interactions between the RTIL and the graphene sheet. In contrast, the RTIL structure adjacent to the charged mica surface exhibits an alternating cation-anion layering extending 3.5 nm into the bulk fluid. The associated charge density profile demonstrates a pronounced charge overscreening (i.e., excess first-layer counterions with respect to the adjacent surface charge), highlighting the critical role of charge-induced nanoscale correlations of the RTIL. These observations confirm key aspects of a predicted electric double layer structure from an analytical Landau-Ginzburg-type continuum theory incorporating ion correlation effects, and provide a new baseline for understanding the fundamental nanoscale response of RTILs at charged interfaces.
Presser, Volker | Vakifahmetoglu, Cekdar
DOI:
This Letter is in response to a recent paper by Ma et al. (CrystEngComm, 2010, 12, 750-754) which arguably studied vanadium carbide nanostructures whereas all available evidence indicates the study of vanadium oxide. We feel that it is important to communicate to the community several inconsistencies so that the interesting material reported can be seen in the right light, especially with several groups nowadays having reported similar structures from vanadium oxide synthesis.