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Diphenylphosphoryl azide ((C6H5O)2P(O)N3, DPPA) was studied by in situ Raman scattering spectroscopy and synchrotron angle‐dispersive X‐ray diffraction (ADXRD) technologies up to 11.6 GPa at room temperature. The analyses of Raman spectra revealed that the liquid DPPA transformed from Phase I to Phase II at 0.4 GPa and went to Phase III at 1.3 GPa. The first phase transition was attributed to the change of molecular conformation, and the second phase transition was induced by the deformation of benzene rings. The XRD results suggested that DPPA remained in a liquid state during the two phase transitions. The azide group became increasingly asymmetric under pressure and decomposed at 11.6 GPa. The low decomposition pressure of the azide group is conducive to the formation of polymeric nitrogen. Exploring the behaviors of the azide group under pressure might be helpful for understanding the potential application of DPPA in the synthesis of high energy density materials (HEDMs). [ABSTRACT FROM AUTHOR]

Described for the first time is that carbon dioxide (CO2) can be successfully inserted into aryl C−H bonds of the backbone of a metal-organic framework (MOF) to generate free carboxylate groups, which serve as Brønsted acid sites for efficiently catalyzing the methanolysis of epoxides. The work delineates the very first example of utilizing CO2 for heterogeneous C−H activation and carboxylation reactions on MOFs, and opens a new avenue for CO2 chemical transformations under mild reaction conditions. [ABSTRACT FROM AUTHOR]

Sulfur intercalated expanded graphite for Li‐S battery cathodes is synthesized by in situ one‐step sulfur reduction and intercalation of graphite oxide (GO). The unique structural reduced graphene oxide (RGO)/S nanocomposite cathodes exhibit high capacity, super rate capability, and long cycle stability. The exceptional electrochemical properties of the RGO/S composites plus their simple fabrication make this class of materials attrac­tive for further investigation in Li‐S batteries applications. [ABSTRACT FROM AUTHOR]

Highly dense oriented arrays of nanotubes were synthesized via a chemical vapor infiltration process using anodic alumina membrane as a template. The nanotubes have a unique granular structure, which is composed of SiC nanocrystals embedded in an amorphous matrix. X-ray diffraction and high-resolution transmission electron microscopy examinations both indicate an NaCl-type crystalline structure of the SiC nanocrystals in the nanotubes. The process described here can be extended to the preparation of other nanomaterials that are suitable to be obtained via a vapor–solid approach. [ABSTRACT FROM AUTHOR]