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The mechanochemical formation of the ionic cocrystals of glucose (Glc) and sodium salts is presented. Products are formed by co-milling Glc with three sodium salts (NaCl, NaBr, NaI). The reaction pathways of the three ionic cocrystals were investigated using our tandem approach comprising a combination of in situ synchrotron powder X-ray diffraction and Raman spectroscopy.
Mechanochemistry paves the way to simple, fast, and green syntheses. Despite considerable effort, there remains a lack in understanding of the underlying mechanisms. In situ investigations help to understand these mechanisms, which occur during a mechanochemical reaction. Here we present a universal strategy for simultaneous real-time in situ analysis, combining X-ray diffraction, Raman spectroscopy, and thermography. The potential of our approach is shown for different model reactions.
Mechanochemistry paves the way to simple, fast, and green syntheses. Despite considerable effort, there is a lack in understanding of the underlying mechanisms. In situ investigations help to understand these mechanisms, which occur during a mechanochemical reaction. Here we present a universal strategy for simultaneous real-time in situ analysis, combining X-ray diffraction, Raman spectroscopy, and thermography. The potential of of our approach is shown for diffrent model reactions.
Metal phosphonates are promising materials for applications in fuel cells, due to their high proton conductivity and higher chemical and thermal stability compared to the industry standard (e.g. Nafion®). Additionally, metal phosphonates are precursors to porous carbon materials with evenly distributed centers for ORR catalysis. As a fast and sustainable synthesis, mechanochemistry is the synthesis method of choice. Thorough characterization is carried out by XRD, MAS-NMR, XAS, BET, and DVS.
Metal phosphonates are metal-organic compounds consisting of a metal core and a phosphonate ligand. Depending on the nature of the ligand, metal phosphonates appear in different structures covering the range from molecular compounds to three-dimensional networks. Due to their structural diversity, the chemistry of metal phosphonates has gained great interest during the last decades. Metal phosphonates can be used for various applications as gas storage and separation, magnetism, and energy conversion. Especially transition metal phosphonates are promising candidates as electrocatalysts. Mechanochemistry is a versatile approach for green and fast synthesis of pure substances. By milling the reactants, various organic, inorganic, and metal-organic compounds can be obtained in high yields. Here, we present the synthesis of different new metal phosphonates obtained by grinding of metal acetates with respective phosphonic acids. By varying the ratio of the reactants, we are able to determine the composition of the final products. The addition of small amounts of liquid to the grinding process tends to increase the product’s crystallinity. The crystal structures of the new compounds were determined from powder X-ray data.
The exploration of metal phosphonates has gained great interest during the last decades, because of their structural diversity. They are promising candidates for a variety of applications ranging from adsorbance to electrocatalysis. The knowledge of the Crystal structure is significant for assigning a coordination polymer for a specific function. We investigated the influence of the fluorination degree of the organic linker on the Crystal packing, the interlayer distance, and the hydrophobicity of the resulting compounds. With fluorinated and nonfluorinated benzylphosphonic acids as starting materials in mechanochemical synthesis, four novel cadmium benzylphosphonates were obtained. Their structures were solved from powder X-ray diffraction.