Water, methane, and ammonia are commonly considered to be the key components of the interiors of Uranus and Neptune. Modelling the planets’ internal structure, evolution, and dynamo heavily relies on the properties of the complex mixtures with uncertain exact composition in their deep interiors. Therefore, characterising icy mixtures with varying composition at planetary conditions of several hundred gigapascal and a few thousand Kelvin is crucial to improve our understanding of the ice giants. In this work, pure water, a water-ethanol mixture, and a water-ethanol-ammonia “synthetic planetary mixture” (SPM) have been compressed through laser-driven decaying shocks along their principal Hugoniot curves up to 270, 280, and 260 GPa, respectively. Measured temperatures spanned from 4000 to 25000 K, just above the coldest predicted adiabatic Uranus and Neptune profiles (3000–4000 K) but more similar to those predicted by more recent models including a thermal boundary layer (7000–14000 K). The experiments were performed at the GEKKO XII and LULI2000 laser facilities using standard optical diagnostics (Doppler velocimetry and optical pyrometry) to measure the thermodynamic state and the shock-front reflectivity at two different wavelengths. The results show that water and the mixtures undergo a similar compression path under single shock loading in agreement with Density Functional Theory Molecular Dynamics (DFT-MD) calculations using the Linear Mixing Approximation (LMA). On the contrary, their shock-front reflectivities behave differently by what concerns both the onset pressures and the saturation values, with possible impact on planetary dynamos.

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Ethane dehydroaromatization (EDA) is a promising method for synthesizing benzene, toluene, and xylene (BTX) to meet the increasing demand for these compounds. Zn2+-ion exchanged MFI-type zeolite (ZnZSM-5) is an active...

Metal–organic frameworks (MOFs) are promising precursors for synthesizing functional carbon materials, and their atomic-scale designs have recently been studied for improving their performance. Herein, we synthesized an alanine-decorated MOF-5 via a solvothermal method using a mixture of dimethylformamide and water as the solvent. Experimental and computational investigations revealed that alanine residues were located in the micropores of MOF-5 due to interactions between the MOF Zn clusters and the carboxylic acid groups of the alanine moieties. In addition, the alanine-decorated MOF-5 was carbonized at 1100 °C for application as an electrocatalyst. It was found that the resulting N-doped carbonized sample exhibited excellent catalytic activities in the oxygen reduction and hydrogen evolution reactions and afforded superior results to those reported for other metal-free carbon catalysts. This high activity originated from the single nitrogen configuration (pyrrolic N) in the hierarchical pores. This article presents a facile strategy for the syntheses of both functionalized MOFs and N-doped carbon materials.

The methanol-to-olefin reactions over SAPO-34 zeolites have been fascinating since the selectivity for valuable light olefins is high. However, the catalyst lifetime is very short due to rapid formation of coke on SAPO-34. Herein, we propose a method to coat the external surface of SAPO-34 nanocrystals with crystalline ZrO2 derived from UiO-66, Zr-based metal–organic frameworks (MOFs), that inhibits coke formation. Powder X-ray diffraction and transmission electron microscopy images implied that the crystalline ZrO2 was accumulated on the external surface of SAPO-34 without any deformation of the crystal structure of SAPO-34. In addition, FTIR spectroscopy using pyridine as a probe molecule indicated that the ZrO2-coated SAPO-34 had no Brønsted acidity on its external surface. The ZrO2-coated SAPO-34 showed a longer catalytic lifetime than unmodified SAPO-34. The absence of acidity on the external surface of the ZrO2-coated SAPO-34 is likely to contribute to the suppression of coke formation on the pore mouths of SAPO-34. This work provides a strategy for the surface modification toward porous nanomaterials including zeolites and MOFs.