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In this context, we report the acoustic shock wave processing on amorphous Carbon quantum dots (a-CQD) such that its degree of graphitization and magnetic properties are analyzed. Analytical techniques such as the Raman spectrometer, high resonation–transmission electron microscopy (HR-TEM) and vibrating sample magnetometer (VSM) are utilized to understand the structural, morphological and magnetic properties changes under shocked conditions. The Raman spectroscopic data reveal that the I D /I G ratio is slightly reduced under shocked conditions and the observed values are 0.78, 0.77 and 0.75 for the respective 0, 150 and 300 shocked conditions. The formation of ultra-short-range graphitic nanostructures is confirmed by HR-TEM results at the 300-shocked condition. The most convincing and supporting results for the enhancement of the degree of graphitization are found by the outcome of the magnetic properties such that the saturation magnetization (Ms) is found to be linearly reduced with respect to the number of shock pulses and the observed values are 0.869, 0.757 and 0.710 emu/g for the 0, 150 and 300 shocked conditions, respectively. The electrical resistance of the a-CQD is found to be linearly reduced with respect to the number of shock pulses due to the reduction of sp3 carbon networks. The formation of crystalline graphitic nanostructures in amorphous CQD is explained on the basis of the hot-spot nucleation mechanism. Based on the obtained Raman, HR-TEM and VSM results, during the shocked conditions, slight enhancement of the graphitization is observed; however, from the structural stability point of view, the Carbon dots have high shock resistance than that of the amorphous carbon nanoparticles, multi-wall carbon nanotubes, and reduced graphene oxide nanoparticles. Hence, the title quantum dots can be strongly considered for the applications of device fabrication. [ABSTRACT FROM AUTHOR]

Rapid progress has been documented during the last couple of years in understanding the crystallographic structural features of a few functional materials that have been achieved under dynamic shock wave loaded conditions. In this context, we report the crystallographic and electronic phase stability of shock wave loaded Cerium oxide nano-crystalline (CeO 2 NPs) material and the results have been evaluated by X-ray diffraction (XRD), Raman spectroscopy and ultra-violet diffuse reflectance spectroscopy (UV-DRS). XRD and Raman spectroscopic results show that the title material doesn't undergo any crystallographic phase transitions. UV-DRS spectral results demonstrate that the Ce4+ ionic state is not affected by the impact of shock waves. The obtained FE-SEM micrographs provide the substantiation for the stability of the sample. Based on the observed results, the title material can be suggested for the making of medical glassware, spaceship windows and technological applications of coating. [ABSTRACT FROM AUTHOR]