Herein the concomitant synthesis of a MoS 2 -and Cu 7 S 4 -decorated graphene aerogel is reported. The material is fully characterized and used as an active material to coat carbon fiber electrodes for the fabrication of a fiber-shaped supercapacitor. The device provides excellent capacitance values warranting stable performance even under high bending angle conditions. Moreover, a photocurable resin is selected as a smart packaging material to overcome stability problems usually affecting this class of devices. It is noteworthy that superior stability is demonstrated with a retention of almost 80% of the initial capacitance after one month. Flexible supercapacitors were also coupled with third-generation solar cells to successfully demonstrate the fabrication of wearable, portable, and integrated smart energy devices.

The aim of this paper is to shed light on the application of graphene oxide (GO) membranes for the selective removal of benzene, toluene, and xylene (BTX) from wastewater. These molecules are present in traces in the water produced from oil and gas plants and are treated now with complex filtration systems. GO membranes are obtained by a simple, fast, and scalable method. The focus of this work is to prove the possibility of employing GO membranes for the filtration of organic contaminants present in traces in oil and gas wastewater, which has never been reported. The stability of GO membranes is analyzed in water solutions with different pH and salinity. Details of the membrane preparation are provided, resulting in a crucial step to achieve a good filtration performance. Material characterization techniques such as electron microscopy, x-ray diffraction, and infrared spectroscopy are employed to study the physical and chemical structure of GO membranes, while gas chromatography, UV-visible spectroscopy, and gravimetric techniques allow the quantification of their filtration performance. An impressive rejection of about 90% was achieved for 1 ppm of toluene and other pollutants in water, demonstrating the excellent performance of GO membranes in the oil and gas field.

The massive worldwide transition of the transport sector to electric vehicles has dramatically increased the demand for lithium. Lithium recovery by means of ion sieves or supramolecular chemistry has been extensively studied in recent years as a viable alternative approach to the most common extraction processes. Graphene oxide (GO) has also already been proven to be an excellent candidate for water treatment and other membrane related applications. Herein, a nanocomposite 12-crown-4-ether functionalized GO membrane for lithium recovery by means of pressure filtration is proposed. GO flakes were via carbodiimide esterification, then a polymeric binder was added to improve the mechanical properties. The membrane was then obtained and tested on a polymeric support in a dead-end pressure setup under nitrogen gas to speed up the lithium recovery. Morphological and physico-chemical characterizations were carried out using pristine GO and functionalized GO membranes for comparison with the nanocomposite. The lithium selectivity was proven by both the conductance and ICP mass measurements on different sets of feed and stripping solutions filtrated (LiCl/HCl and other chloride salts/HCl). The membrane proposed showed promising properties in low concentrated solutions (7 mgLi/L) with an average lithium uptake of 5 mgLi/g in under half an hour of filtration time.

flexible devices is still long and full of obstacles that strongly obstruct the development of such systems. [3] Among the main limitations, it is possible to observe that there is an urgency of effective strategies to obtain conductive paths onto flexible substrates. [4] Moreover, even if the flexibility is mandatory, stretchable substrates are even more desired since the portable device sector is moving toward a wearable configuration. This implies that it is not possible to keep flexibility and stretchability separated.In this context, laser induced graphene is emerging, in the large family of graphene-based materials, [5] as one of the most promising materials for the fabrication of flexible electronic devices. [6] However, despite the endless efforts spent to develop LIG on new substrates there is a lack of stretchable polymers suitable for laser graphenization. [7] Indeed, up to now the evidence of graphenization of elastomeric substrate has never been observed.Considering the family of elastomer polymers, polydimethylsiloxane (PDMS) represents the most popular elastomeric material in microsystem technology thanks to its attractive physical and chemical properties such as elasticity, optical transparency down to 220 nm, tunable surface chemistry, low water permeability but high gas permeability and high dielectric properties. Moreover, it is a cost-effective material and allows the development of reliable mass replication technique. [8] Unfortunately, it cannot be easily graphenized by direct laser writing because of the low amount of carbon linked to the siloxane chains, mainly consisting of methyl groups. For this reason, some research groups proposed the transfer of a LIG layer produced onto polyimide onto PDMS by simple infiltration of the uncured elastomer into the LIG network and subsequent peeling after the PDMS cross-linking. [9] This strategy allows to achieve stretchable electrodes, but strongly affects the conductivity of the transferred layer reducing its available surface area. [10] Moreover, the two-step process increases the fabrication time and complexity reducing the degrees of freedom during sample production.We recently proposed an easy way to overcome the abovementioned limitation by exploiting an innovative composite of polyimide microparticles dispersed into PDMS matrix. [11] The particles undergo a perfect graphenization during laser writing, but such procedure cannot solve all the problems previously discussed. In these composites the conductivity remains

This paper presents a critical review and the state of the art of graphene porous membranes, a brand-new technology and backdrop to discuss its potential application for efficient water desalination in low salinity water injection (LSWI). LSWI technology consists in injecting designed, adequately modified, filtered water to maximize oil production. To this end, desalination technologies already available can be further optimized, for example, via graphene membranes, to achieve greater efficiency in water-oil displacement. Theoretical and experimental applications of graphene porous membranes in water desalination have shown promising results over the last 5-6 years. Needless to say, improvements are still needed before graphene porous membranes become readily available. However, the present work simply sets out to demonstrate, at least in principle, the practical potential graphene membranes would have in hydrocarbon recovery processes.

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Graphene oxide (GO) membranes have been proved to be ion-selective thanks to their oxidized functional groups, which are naturally present on its surface. This ion selectivity, together with good mechanical strength, low cost, and simple synthesis, makes GO a great alternative material to conventional costly polymers for the production of ion-exchange membranes. This work focuses on how to produce GO membranes as ion-exchange membranes with a scalable approach and tunable permselectivity. Their physicochemical properties were subsequently investigated by means of selected characterization techniques. Results showed that GO membranes present good ion selectivity and size exclusion towards monovalent cations, reaching a permselectivity of up to 96%. Interestingly, UV-light irradiation of GO membranes can also be proposed as a green reduction method. GO reduction increases the permselectivity due to both a decrease in the dimension of the nanochannels and a reduction in the swelling degree of the membranes. The addition of binders was also investigated to improve the membranes’ mechanical properties. Finally, the ionic resistance of the membranes was measured by impedance spectroscopy, achieving 4.6 Ω cm2, orders of magnitude lower than the state-of-the-art graphene oxide-based membranes.

Graphene oxide (GO) has shown great potential as a membrane material due to its unique properties, including high mechanical strength, excellent thermal stability, versatility, tunability, and outperforming molecular sieving capabilities. GO membranes can be used in a wide range of applications, such as water treatment, gas separation, and biological applications. However, the large-scale production of GO membranes currently relies on energy-intensive chemical methods that use hazardous chemicals, leading to safety and environmental concerns. Therefore, more sustainable and greener approaches to GO membrane production are needed. In this review, several strategies proposed so far are analyzed, including a discussion on the use of eco-friendly solvents, green reducing agents, and alternative fabrication techniques, both for the preparation of the GO powders and their assembly in membrane form. The characteristics of these approaches aiming to reduce the environmental impact of GO membrane production while maintaining the performance, functionality, and scalability of the membrane are evaluated. In this context, the purpose of this work is to shed light on green and sustainable routes for GO membranes’ production. Indeed, the development of green approaches for GO membrane production is crucial to ensure its sustainability and promote its widespread use in various industrial application fields.