Contribution to the understanding of tribological properties of graphite intercalation compounds with metal chloride

Intrinsic tribological properties of lamellar compounds are usually attributed to the presence of van der Waals gaps in their structure through which interlayer interactions are weak. The controlled variation of the distances and interactions between graphene layers by intercalation of electrophilic species in graphite is used in order to explore more deeply the friction reduction properties of low-dimensional compounds. Three graphite intercalation compounds with antimony pentachloride, iron trichloride and aluminium trichloride are studied. Their tribological properties are correlated to their structural parameters, and the interlayer interactions are deduced from ab initio bands structure calculations

A reference high-pressure CH₄ adsorption isotherm for zeolite Y: results of an interlaboratory study

This paper reports the results of an international interlaboratory study led by the National Institute of Standards and Technology (NIST) on the measurement of high-pressure surface excess methane adsorption isotherms on NIST Reference Material RM 8850 (Zeolite Y), at 25 °C up to 7.5 MPa. Twenty laboratories participated in the study and contributed over one-hundred adsorption isotherms of methane on Zeolite Y. From these data, an empirical reference equation was determined, along with a 95% uncertainty interval (Uk=2). By requiring participants to replicate a high-pressure reference isotherm for carbon dioxide adsorption on NIST Reference Material RM 8852 (ZSM-5), this interlaboratory study also demonstrated the usefulness of reference isotherms in evaluating the performance of high-pressure adsorption experiments

Model-based optimization of solid oxide electrolysis cells and stacks for powerto- gas applications

Power-to-Methane (PtM) is an attractive chemical storage concept enabling the coupling of intermittent renewable energy sources with the gas grid. Here, we use a combined experimental and modeling methodology to investigate and optimize solid oxide electrolysis cells (SOECs) and stacks operation for PtG applications. Firstly, electrode- and electrolyte-supported single cells from commercial suppliers are characterized in terms of their electrochemical performance and their microstructure. By implementing the structural data into a detailed single cell model and by reproducing steady-state polarization curves, the model is calibrated and validated for both cell designs. Subsequently, 2D adiabatic simulations are conducted to examine the performance of both cell types in detail. Afterwards, a scale-up to the 3D stack level is performed to correlate the model-predicted stack performance with that of a single repeating unit, which illustrates the implications of scaling-up on the SOEC performance. These analyses can provide valuable guidelines for cell and stack design considerations for PtM applications

Synthesis of nanoscale metal particles

International audienc

Systematic review: human gut dysbiosis induced by non-antibiotic prescription medications

International audienc