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With the rapid development of high-power-density electronic devices, interface thermal resistance has become a critical barrier for effective heat management in high-performance electronic products. Therefore, there is an urgent demand for advanced thermal interface materials (TIMs) with high cross-plane thermal conductivity and excellent compressibility to withstand increasingly complex operating conditions. To achieve this aim, a promising strategy involves vertically arranging highly thermoconductive graphene on polymers. However, with the currently available methods, achieving a balance between low interfacial thermal resistance, bidirectional high thermal conductivity, and large-scale production is challenging. Herein, we prepared a graphene framework with continuous filler structures in in-plane and cross-plane directions by bonding corrugated graphene to planar graphene paper. The interface interaction between the graphene paper framework and polymer matrix was enhanced via surface functionalization to reduce the interface thermal resistance. The resulting three-dimensional thermal framework endows the polymer composite material with a cross-plane thermal conductivity of 14.4 W·m−1·K−1 and in-plane thermal conductivity of 130 W·m−1·K−1 when the thermal filler loading is 10.1 wt%, with a thermal conductivity enhancement per 1 wt% filler loading of 831%, outperforming various graphene structures as fillers. Given its high thermal conductivity, low contact thermal resistance, and low compressive modulus, the developed highly thermoconductive composite material demonstrates superior performance in TIM testing compared with TFLEX-700, an advanced commercial TIM, effectively solving the interfacial heat transfer issues in electronic systems. This novel filler structure framework also provides a solution for achieving a balance between efficient thermal management and ease of processing. [ABSTRACT FROM AUTHOR]

Flexible graphene‐based paper electrodes (FGPEs) are a new class of study and the research on this electrode material has been carried out for approximately ten years. FGPEs have many advantages compared to classical solid electrodes such as being flexible, foldable, adaptable to flexible electronics, being cut, easily shaped, and effective and adjustable modification. In this work, the applicability of FGPEs modified with polyindole (PIN) thin films and zinc oxide nanoparticles (ZnO‐NPs) to energy‐storage systems as a supercapattery design is presented, and especially the limitations of ZnO‐NPs for energy‐storage applications are revealed to inform researchers working for a similar purpose. Capacitance calculations have been performed using both cyclic voltammetry (CV) and galvanostatic charge‐discharge (GCD) experiments. It was observed that the rGO/PIN paper demonstrated almost 30 times more energy‐storage capacity than that of the rGO/PIN/ZnO paper due to the electrochemical instability of ZnO‐NPs on the flexible electrode platform at the applied potential region in 1.0 M HClO4 solution. The rGO/PIN paper with a highly flexible property exhibited an energy density of 74.5 W h cm−2 and a power density of 2258 W cm−2 at a current density of 2.2 mA cm−2, revealing hopeful results for future modular and flexible approaches. [ABSTRACT FROM AUTHOR]

This paper presents the results of research on the impact of graphene paper on selected bacterial strains. Graphene oxide, from which graphene paper is made, has mainly bacteriostatic properties. Therefore, the main goal of this research was to determine the possibility of using graphene paper as a carrier of a medicinal substance. Studies of the degree of bacterial inhibition were performed on Staphylococcus aureus and Pseudomonas aeruginosa strains. Graphene paper was analyzed not only in the state of delivery but also after the incorporation of the antibiotics ciprofloxacin, cefazolin, and methicillin into its structures. In addition, Fourier-Transform Infrared Spectroscopy, contact angle, and microscopic analysis of bacteria on the surface of the examined graphene paper samples were also performed. Studies have shown that graphene paper with built-in ciprofloxacin had a bactericidal effect on the strains of Staphylococcus aureus and Pseudomonas aeruginosa. In contrast, methicillin, as well as cefazolin, deposited on graphene paper acted mainly locally. Studies have shown that graphene paper can be used as a carrier of selected medicinal substances. [ABSTRACT FROM AUTHOR]

We present a facile one-step hydrothermal method for the fabrication of free-standing graphene paper using aqueous graphene oxide (GO) dispersion as the starting material. Notably, the method does not require the use of any additives for the reduction and preparation of the graphene paper. The resulting graphene paper exhibits a high degree of reduction, as confirmed by X-ray photoelectron spectroscopy (XPS) analysis, revealing a carbon-to-oxygen (C/O) ratio of ∼7. The fabricated graphene paper also demonstrates excellent conductivity, with a measured value of ∼1900 S/m, and sheet resistance of around 100 Ω/sq. Furthermore, the energy storage capability of the graphene paper based electrode is evaluated, which shows a promising specific capacity of 249 F/g at a current density of 1 A/g in 1M H2SO4 as the ionic medium. Additionally, the electrode has also demonstrated remarkable energy density and power density values of 28.68 Wh/Kg and 455 W/Kg, respectively. Overall, the resulting graphene paper exhibits high conductivity and excellent electrochemical performance, making it a promising candidate for various energy storage applications.

This paper presents the results of research on the impact of graphene paper on selected bacterial strains. Graphene oxide, from which graphene paper is made, has mainly bacteriostatic properties. Therefore, the main goal of this research was to determine the possibility of using graphene paper as a carrier of a medicinal substance. Studies of the degree of bacterial inhibition were performed on Staphylococcus aureus and Pseudomonas aeruginosa strains. Graphene paper was analyzed not only in the state of delivery but also after the incorporation of the antibiotics ciprofloxacin, cefazolin, and methicillin into its structures. In addition, Fourier-Transform Infrared Spectroscopy, contact angle, and microscopic analysis of bacteria on the surface of the examined graphene paper samples were also performed. Studies have shown that graphene paper with built-in ciprofloxacin had a bactericidal effect on the strains of Staphylococcus aureus and Pseudomonas aeruginosa. In contrast, methicillin, as well as cefazolin, deposited on graphene paper acted mainly locally. Studies have shown that graphene paper can be used as a carrier of selected medicinal substances.

We report for the first time a one-step fabrication by lamination of inexpensive graphene paper (GP) based Ag/AgCl pseudo-reference (RE) and K+-selective coated-film electrodes forming the novelty of this work. Contrary to our previous work about laminated GP solid-contact electrodes, the electrode fabrication in this work does not require manual drop casting steps after the lamination, simplifying the fabrication and making it suitable for mass production. We also eliminated the need of the solid contact and simplified the electrode construction by placing the plasticized potassium-selective PVC membrane (ISM) directly on the GP functioning as combined electrode substrate and ion-to-electron transducer. Both Ag/AgCl and the ISMs were pre-deposited on rectangular GP sheets (10 ×100 mm2) before placing them inside laminating pouches and feeding them through an office laminator after which the electrodes were ready for use. Five batches of 32 pseudo-REs had a very good E 0 reproducibility of ± 2.8 mV. The K+-electrodes had a slope and detection limit of 57.4 ± 0.3 mV/pK (n = 4) and 6 × 10−7 M, and the E 0 reproducibility was in the best case only ± 1.2 mV matching the performance of non-laminated K+-electrodes. This work demonstrates that the ISMs are compatible with the lamination where the temperature can momentarily rise to ca. 130 °C. [Display omitted] • Hot lamination of planar and flexible graphene paper based pseudo-REs and ISEs. • One-step fabrication by lamination of low-cost electrodes that are suitable for mass production. • The Ag/AgCl pseudo-REs had a good batch-to-batch E 0 reproducibility of ± 2.8 (n = 32). • The K+-ionophore valinomycin does not degrade during hot lamination at ca. 130 °C. • Laminated K+-selective electrodes match the performance of non-laminated ones. [ABSTRACT FROM AUTHOR]