In recent decades, photoluminescence (PL) material with excellent optical properties has been a hot topic. Graphene oxide (GO) is an excellent candidate for PL material because of its unique optical properties, compared to pure graphene. The existence of an internal band gap in GO can enrich its optical properties significantly. Therefore, GO has been widely applied in many fields such as material science, biomedicine, anti-counterfeiting, and so on. Over the past decade, GO and quantum dots (GOQDs) have attracted the attention of many researchers as luminescence materials, but their luminescence mechanism is still ambiguous, although some theoretical results have been achieved. In addition, GO and GOQDs have fluorescence quenching properties, which can be used in medical imaging and biosensors. In this review, we outline the recent work on the photoluminescence phenomena and quenching process of GO and GOQDs. First, the PL mechanisms of GO are discussed in depth. Second, the fluorescence quenching mechanism and regulation of GO are introduced. Following that, the applications of PL and fluorescence quenching of GO–including biomedicine, electronic devices, material imaging–are addressed. Finally, future development of PL and fluorescence quenching of GO is proposed, and the challenges exploring the optical properties of GO are summarized.

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Water uptake, adhesion and corrosion performance of silicone-epoxy coating on 2024 Al-alloy treated with different GLYMO were systematically studied by gravimetry, electrochemical measurements, DSC, pull-off adhesion and salt spray tests. The results showed that GLYMO not only enhanced the cross-linking of the silicon-epoxy coating but also enhanced the bonding between the coating and the Al-alloy interface. This gives the coating better wet adhesion, less water absorption and improves the corrosion resistance of the coating. The micro-nano silane layer, preferentially between the coating and Al-alloy oxide layer, was validated by the model of the water concentration jump.

The efficient exfoliation of mica, a naturally layered material, into two-dimensional (2D) nanosheets has received much attention due to its low price, good chemical stability, and better shielding function against UV light. However, fast and simple exfoliation of mica in a large-scale face a great challenge. In this work, we developed a simple and effective method for obtaining OH−functionalized mica nanosheets (MNs). The process involved calcination, plasma treatment, and ultrasonic exfoliation, resulting in a yield of 7.535%. Furthermore, the effects of sonication time, solvent type, and particle sizes of mica were investigated. The conditions for the preparation of MNs were determined: mica calcination, plasma treatment, and sonication in ethanol for 5 h. XPS and FT−IR demonstrated that more hydroxyl groups were introduced to mica after the plasma treatment, which facilitated the exfoliation of mica.