In this study, graphene oxide (GO) nanosheets were modified with an amine functional group to obtain amine-functionalized graphene (AMG) nanosheets and then blended with the aniline curing agent of bisphenol-A (BPA) epoxy resin to crosslink BPA epoxy resin. The AMG-blended curing agent and BPA epoxy resin formed an intermolecular hydrogen bond that was stronger than the π–π stacking force between benzene rings of graphene nanosheets. Therefore, AMG nanosheets exhibited excellent dispersion in the aniline curing agent. The amine group of AMG-blended curing agents and the epoxy functional group of BPA epoxy resin exhibited strong chemical activity and underwent crosslinking and polymerization. AMG nanosheets were mixed with BPA epoxy resin to form a crosslinked structure through the epoxy ring-opening polymerization of the resin. The mechanical properties of the epoxy resin nanocomposites were significantly improved by the added 1 wt.% AMG nanosheets. The tensile strength was enhanced by 98.1% by adding 1 wt.% AMG in epoxy. Furthermore, the impact resistance of the epoxy resin was enhanced by 124.4% after adding 2.67 wt.% of AMG nanosheets. Compared with other reinforced fillers, AMG nanosheets are very light and can therefore be used as nanocomposite materials in coating applications, the automotive industry, aerospace sheet materials, wind power generation, and other fields.

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The quality of Li-ion batteries is highly related to the crystallinity of the graphite used in their electrodes. Therefore, the development of two-dimensional detection equipment for evaluating the integrity of graphite electrodes is critical. In this study, a triaxial scanning platform was developed for Raman spectroscopy. Two-dimensional Raman mapping of the defects (D band) and stacking (2D band) of graphite electrodes was performed to determine atomic-level variations caused by charging. Through Raman mapping, the effects of constant-current-constant-voltage (CC-CV) and CC-reFLEX fast charging were compared. The graphite damage from CC-reFLEX fast charging was less extensive than that from CC-CV charging. Furthermore, investigations using the triaxial platform revealed that the graphite on a curved electrode exhibited disordered stacking after several charging-discharging cycles. This phenomenon creates safety concerns.

Chromia-forming ferritic stainless steel (FSS) is a highly promising interconnect material for application in solid oxide fuel cells. In this study, initial oxidation of chromium oxides was performed at 500–800 °C to understand the evolution of materials at an early stage. The structural variations in oxide scales were analyzed through scanning electron microscopy, energy dispersive spectroscopy (EDS), transmission electron microscopy (TEM), X-ray diffractometry (XRD), laser confocal microscopy (LSCM), X-ray photoelectron spectroscopy (XPS), and Raman spectroscopy. Surface electrochemical properties were investigated through electrochemical impedance spectroscopy to understand how the heat treatment temperature affected surface impedance. Treatment temperatures higher than 700 °C facilitate the diffusion of Cr and Mn, thus allowing ferritic spinels to form on the surface and leading to high electrical conductivity.