Elucidating the Sorption Mechanism of Dibromomethane in Disordered Mesoporous Silica Adsorbents

A review of recent developments for the in situ/operando characterization of nanoporous materials

This is a review on up-to-date in situ/operando methods for a comprehensive characterization of nanoporous materials. The group of nanoporous materials is constantly growing, and with it, the variety of...

Pore Size Gradient Effect in Monolithic Silica Mesopore Networks Revealed by In-Situ SAXS Physisorption

In disordered mesopore networks, the size distribution and connection between adjacent pores control desorption. How network characteristics can be extracted from corresponding physisorption isotherms is still a matter of research. To elucidate this, we study krypton physisorption (117.8 K) in the mesopore networks of "Nakanishi"-type monolithic silica. Combining physisorption in scanning acquisition mode with synchrotron-based in-situ SAXS provides complementary information on pore-filling states. These data reveal a mean pore size gradient in which pores grow smaller towards the material's network center. This structural motif cannot be derived through conventional isotherm analysis, but it is clearly exposed through scanning desorption curves which do not quite converge but merge individually with the main desorption isotherm before the lower hysteresis closing point. Hence, our findings provide the basis to build advanced models for analyzing scanning isotherms and extracting network characteristics through new descriptors, such as pore size and connectivity distributions as a function of the distance from the network center.

Real-time powder diffraction studies of energy materials under non-equilibrium conditions

Energy materials form the central part of energy devices. An essential part of their function is the ability to reversibly host charge or energy carriers, and analysis of their phase composition and structure in real time under non-equilibrium conditions is mandatory for a full understanding of their atomic-scale functional mechanism. Real-time powder diffraction is increasingly being applied for this purpose, forming a critical step in the strategic chemical engineering of materials with improved behaviour. This topical review gives examples of real-time analysis using powder diffraction of rechargeable battery electrodes and porous sorbent materials used for the separation and storage of energy-relevant gases to demonstrate advances in the insights which can be gained into their atomic-scale function.

Enhanced photodegradation of dyes and mixed dyes by heterogeneous mesoporous Co–Fe/Al2O3–MCM-41 nanocomposites: nanoparticles formation, semiconductor behavior and mesoporosity

Fabrication of mono and bimetallic nanoparticles by in situ sol–gel cum hydrothermal method for photo degradation of dyes and mixed dyes.

Hierarchically porous monolithic silica with varying porosity using bis(trimethoxysilyl)arenes as precursors

Isomers of bis-(trimethoxysilyl)arenes were synthesized and used as organosilica precursors for the preparation of macro-mesoporous hybrid silica monoliths.