Sol–gel based synthesis and enhanced processability of MAX phase Cr2GaC. Issue 20 (2nd May 2019)

• Record Type: Journal Article
• Authors: Siebert, Jan Paul; Bischoff, Lothar; Lepple, Maren; Zintler, Alexander; Molina-Luna, Leopoldo; Wiedwald, Ulf; Birkel, Christina S.
• Is Part Of: Journal of materials chemistry. Volume 7:Issue 20(2019)
• Page Start: 6034
• Page End: 6040
• Publication Date: 2019-05-02
• Subjects: Materials -- Periodicals; Chemistry, Analytic -- Periodicals; Optical materials -- Research -- Periodicals; Electronics -- Materials -- Research -- Periodicals; 543.0284
• DOI: 10.1039/c9tc01416k
• Languages: English
• ISSNs: 2050-7526

Abstract

Abstract : New and facile wet chemistry based synthesis method for the preparation and processing of MAX phase Cr2 GaC. Abstract : MAX phases are typically prepared by high-temperature (oftentimes high-pressure) solid-state methods. Here, we report a new wet chemistry based synthesis technique starting from an aqueous solution of metal nitrates and citric acid to prepare MAX phase Cr2 GaC. This solution-processable precursor mixture has the potential to be easily scaled, painted, printed or fabricated onto supports – an advantage that is demonstrated by the formation of hollow carbon microspheres which are decorated with Cr2 GaC particles. A small amount of chromium carbide and oxide remains in the product, however, the amount of the latter can be reduced by a larger excess in citric acid in the precursor gel. The transformation mechanism of the initial amorphous gel into highly crystalline and anisotropic MAX phase particles is investigated by detailed thermal analysis. Transmission electron microscopy studies are conducted to elucidate the microstructure of the sol–gel-prepared particles as well as the decorated hollow microspheres. From magnetic susceptibility measurements, the density of states at the Fermi level is deduced reflecting the quality of the Pauli paramagnet Cr2 GaC.