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The incorporation of nitrogen (N) atoms into a graphitic network such as graphene (Gr) remains a major challenge. However, even if the insertion mechanisms are not yet fully understood, it is certain that the modification of the electrical properties of Gr is possible according to the configuration adopted. Several simulations work, notably using DFT, have shown that the incorporation of N in Gr can induce an increase in the electrical conductivity and N acts as an electron donor; this increase is linked to the amount of N, the sp2/sp3 carbon configuration, and the nature of C−N bonding. Nitrogen radiofrequency (RF) plasma has been used to incorporate N into Gr materials. The RF plasma method shows the possibility to incorporate N‐graphitic nitrogen into Gr after a pre‐treatment with nitric acid. X‐ray photoelectron spectroscopy and Raman spectrometry were used to quantify the functionalized groups. The modifications of the graphene surface chemistry along the amount of N inside the Gr change the chemical environment of N. This method, enabling the incorporation of N inside Gr matrix, opens up a route to a broad range of applications. [ABSTRACT FROM AUTHOR]

Herein we introduce a powerful and fast method to produce nanominerals using a bottom up approach. The supercritical hydrothermal flow synthesis is exploited to produce model nanominerals by mimicking natural environments at high temperatures under pressure. This innovative concept is demonstrated with the talc synthesis; this represents a major technical breakthrough since it allows decreasing the mineral-synthesis time from tens of hours to tens of seconds. Through this example, we show these nanominerals exhibit new crystal-chemistry signals and new properties. This approach provides a means to reproduce the early stages of formation of minerals in different natural environments from sedimentary environments (low temperature and pressure) to hydrothermal/metamorphic environments (high temperature and high pressure). [ABSTRACT FROM AUTHOR]

Geomimetik bezeichnet einen innovativen Ansatz, bei dem neue Materialien nach dem Vorbild der Mineralwelt hergestellt werden. In der Natur entsteht Talk im Laufe von Jahrmillionen durch Hydrothermalprozesse in festem Gestein. F. Martin, C. Aymonier et al. beschreiben in der Zuschrift auf S. 10022 ff. eine geomimetische Synthese von Talk innerhalb von 20 s in einem kontinuierlichen Fließreaktor unter überkritischen Bedingungen (SCF). Der synthetische Nano ‐ Talk hat neue kristallchemische Signale und Eigenschaften (Hydrophilie), die neue Anwendungsmöglichkeiten eröffnen. [ABSTRACT FROM AUTHOR]

The cover page of the journal "Angewandte Chemie" is presented.