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Herein, an electrochemical technique as a cost-effective and one-step approach was utilized to fabricate graphene quantum dots (GQDs). Different amounts of GQDs (0, 0.2, 0.4, 0.8, and 1.2 wt %) were decorated uniformly on the surface of anodized ZnO nanowires (NWs) forming GQD/ZnO NWs. Transmission electron microscopy and atomic force microscopy confirmed formation of GQDs on the ZnO NWs, 12–22 nm in width and 1–3 graphene layers thick. X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy were employed to verify the functional groups on the surface of GQDs, and the results indicated that GQDs readily anchored on the surface of ZnO NWs. The GQD/ZnO NWs exhibited a considerable improvement on the photocatalytic degradation of methylene blue under solar irradiation, due to efficient light absorption. In addition, the results indicated that the optimized GQD (0.4 wt %)/ZnO NWs showed the highest photoactivity with about 3-fold enhancement as compared to pure ZnO NWs. Finally, a mechanism of charge carrier generation, transport, and separation was proposed using different scavengers to probe the potential reaction pathway following a direct Z-scheme approach.

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Amphiphilic surfaces, containing both hydrophilic and hydrophobic domains, offer desirable performance for many applications such as marine coatings or anti-icing purposes. This work explores the effect of the concentration of amphiphilic moieties on converting a polyurethane (PU) system to a coating having fouling-release properties. A novel amphiphilic compound is synthesized and added at increasing amounts to a PU system, where the amount of the additive is the only variable in the study. The additive-modified surfaces are characterized by a variety of techniques including ATR-FTIR, XPS, contact angle measurements, and AFM. Surface characterizations indicate the presence of amphiphilic domains on the surface due to the introduction of the selfstratifying amphiphilic additive. The fouling-release properties of the surfaces are assessed with three biological assays using Ulva linza, Cellulophaga lytica, and Navicula Incerta as the test organisms. A change in the fouling-release performance is observed and plateaued once a certain amount of amphiphilicity is attained in the coating system, which we call the critical amphiphilic concentration (CAC).

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with exceptional mechanical resilience, self-healing properties, and processability have been reported recently. [16] Although hydrogel composites remain useful materials for sensor and biomedical applications, broad use is restricted by their operating temperature range (0−100 °C), long-term stability, and the need for watersoluble reagents.Conductive organogel composites have received comparatively little attention despite the ability to support a wide range of polymers and fillers, exhibit conductivities between 10 −4 and 10 mS cm −1 , [17] and maintain useful mechanical and electrical properties at temperature extremes without solvent evaporation or freezing. [18] Furthermore, the synthetic tunability of organogels provides access to a diverse range of materials. For example, dynamic organogels can be synthesized with reversible covalent bonds or secondary interactions such as hydrogen bonding to facilitate self-healing, network reversion, or sensing capabilities. [19][20][21][22][23][24][25][26][27] Variability in solvent, polymer, and filler selection allows access to materials mimicking the mechanical properties of hydrogel composites and soft conductive elastics, and enables performance inaccessible to either system alone such as stimuli responsivity and temperature stability. Recyclable hemiaminal dynamic covalent networks (HDCNs) formulated with insulating polyethylene glycol (PEG) and conductive fillers present advantages in applications such as pressure and chemical sensors, antistatic technologies, and other flexible electronics. [27][28][29][30][31][32] A survey of conductive nanoparticles was added to HDCN organogels during their synthesis in N-methyl-2-pyrrolidone (NMP): "long" (10 µm × 12 nm) multi-walled carbon nanotubes (MWCNTs), four types of carbon black (Black Pearls L (BPL), 9A32, XC72, XC72R), and graphite. Microscale behaviors were first established through rheology. HDCN composites remained in a dynamic state, underwent stress relaxation up to 2 h after formation, and had relaxation stretching parameters close to zero (β = 0.01−0.09, R 2 ≈ 0.95, Table S1, Supporting Information), independent of solvent and filler choice. The stretched relaxation behavior was attributed to hierarchical and continuous segmental relaxation from the dynamic heterogeneity of transient networks. Transient covalent crosslinks and supramolecular interactions are active throughout the gel at various length scales and stages of relaxation, changing the kinetics of chain motion as a function of their fluctuation, and creating a wide distribution of relaxation behaviors over long time periods. [33][34][35][36][37] Notably, β values for composites were comparable to the matrix alone (β = 0.02), suggesting uniform filler Conductive OrganogelsAs the use of automation in industry accelerates, the development of flexible, electrically conducting materials with the requisite environmental resilience for impact-resistant sensors, foldable electronics, and electrostatic shielding are needed; simultaneously, recyclability fo...

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