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Among the many potential applications of graphene and graphene-based materials, their use as protective films or as additives in coatings for corrosion protection has seen an increased level of interest in the last decade. Much of this interest is motivated by the need to implement additional functionalities, to enhance anti-corrosion performance and to ultimately extend the service life of metallic structures. Pristine graphene films, with their impermeable nature allied to flexibility and mechanical strength, appear as particularly attractive candidates for barrier films against corrosive agents, while graphene-based materials such as graphene oxide and reduced graphene oxide offer a wide range of opportunities for their dispersion in polymeric matrices for composite anti-corrosive coatings. Simultaneously, considerable progress in the development of scalable graphene and graphene-based materials production techniques has been made during the last several years. Currently, a broad range of graphene materials with different morphologies and properties is available, making the need for an adequate fit between the production method and the desired application even more evident. This review article aims to give the reader a general overview of the recent trends in both the production of graphene and graphene-based materials, and their implementation in different anti-corrosion solutions. Moreover, the present work provides a critical look on this subject, highlighting the areas in need of further exploration. published

There are several applications and innovations of graphene that can change the world in the areas of energy, health, and electro-electronics. Graphene is ideal for bringing together the research sector and the industry, considering that the potential market is huge, as well as profitability. The purpose of this chapter is to present social, economic, ethical, and legal issues involving graphene. Among the existing research with the use of graphene, we can highlight an antibacterial role, acceleration of the internet, membranes that capture carbon dioxide. The global graphene market has an average annual growth of 32%. There is also a manual on processes for making graphene. However, intellectual property must be used in a way that respects its social function and further research on graphene is necessary due to the market trend and applications in several areas.

Concrete is the most widely used construction material, however, concrete structures often suffer from poor durability and require frequent inspections and repairs. Concrete production is also associated with high carbon emissions and the large-scale depletion of natural resources. Recently, the addition of graphene nanoplatelets (GNPs) in cementitious materials has shown a potential to improve the performance and instigate additional functionalities. However, there is limited understanding around the environmental effects from the production of GNP and its incorporation in concrete. This study has investigated, by means of a Life Cycle Assessment (LCA), the environmental impact of concrete reinforced with graphene nanoplatelets by focusing on the “cradle-to-gate” of GNP production and their incorporation in concrete. The production of 1 kg of G2NanPaste (GNPs product) is found to result in 0.17 kgCO2 equivalent units which is lower than Portland cement (0.86 kgCO2 eq). Ordinary Portland cement (CEM I) is 248 times more damaging than G2NanPaste in terms of global warming. The superplasticiser addition is found to have a greater environmental impact compared to G2NanPaste. The sensitivity analysis showed that if the addition of GNPs results in a 5% reduction of the Portland cement, the effect of the concrete mix on global warming can be reduced by 21%. This indicates that GNPs could be environmentally friendly if used as a supplement for some of the cement. The main aim of this paper is to perform the first LCA of the addition of graphene nanoplatelets in concrete. It is hoped that this work will pave the way for further research in this area.

In recent years, graphene has found its use in numerous industrial applications due to its unique properties. While its impermeable and conductive nature can replace currently used anticorrosive toxic pigments in coating systems, due to its large strength to weight ratio, graphene can be an important component as a next-generation additive for automotive, aerospace and construction applications. The current bottlenecks in using graphene and graphene oxide and other two-dimensional materials are the availability of cost-effective, high-quality materials and their effective incorporation (functionalization and dispersion) into the product matrices. On overcoming these factors, graphene may attract significant demands in terms of volume consumption. Graphene can be produced on industrial scales and through cost-effective top-down routes such as chemical, electrochemical and/or high-pressure mechanical exfoliation. Graphene, depending on end applications, can be chemically tuned and modified via functionalization so that easy incorporation into product matrices is possible. This paper discusses different production methods and their impact on the quality of graphene produced in terms of energy input. Graphene with an average thickness below five layers was produced by both methods with varied defects. However, a higher yield of graphene with a lower number of layers was produced via the high-pressure exfoliation route. This article is part of a discussion meeting issue ‘A cracking approach to inventing new tough materials: fracture stranger than friction’.

A simple and inexpensive method for the production of graphene-based masterbatch via polymer-assisted shear exfoliation of graphite in water was comprehensively investigated. In detail, a modified polyvinyl alcohol (mPVOH) characterized by surface energy comparable with that of graphene was used as surfactant for the production of graphene-like particles. The proposed approach allowed a yield in graphene-like particles higher than that obtained by using common surfactants, along with a narrower size distribution. A mPVOH-masterbatch containing 4.38 wt% of graphene-like particles was produced by removing the aqueous solvent from a dispersion and directly used for production of polymer nanocomposites by melt processing. Films prepared by blending the masterbatch with polyvinyl alcohol in order to have a graphene-like particles content equal to 0.3 wt% showed a 78% reduction in water permeability and a 48% increase in storage modulus as compared with pristine polymers. Improved barrier properties were also observed for polylactic acid (PLA) and low-density polyethylene (LDPE)-based composite films, whereas an increment of about 520% in the storage modulus was observed for the composite obtained with PLA. The obtained results are very relevant and the proposed process will open up a new pathway for using graphene-based masterbatch in the packaging industry. Keywords: Graphene production, Graphene masterbatch, Polymer composite, Barrier and mechanical properties, Packaging

Biological interfacing of graphene has become crucial to improve its biocompatibility, dispersability, and selectivity. However, biofunctionalization of graphene without yielding defects in its sp2-carbon lattice is a major challenge. Here, a process is set out for biofunctionalized defect-free graphene synthesis through the liquid phase ultrasonic exfoliation of raw graphitic material assisted by the self-assembling fungal hydrophobin Vmh2. This protein (extracted from the edible fungus Pleurotus ostreatus) is endowed with peculiar physicochemical properties, exceptional stability, and versatility. The unique properties of Vmh2 and, above all, its superior hydrophobicity, and stability allow to obtain a highly concentrated (≈440–510 μg mL−1) and stable exfoliated material (ζ-potential, +40/+70 mV). In addition controlled centrifugation enables the selection of biofunctionalized few-layer defect-free micrographene flakes, as assessed by Raman spectroscopy, atomic force microscopy, scanning electron microscopy, and electrophoretic mobility. This biofunctionalized product represents a high value added material for the emerging applications of graphene in the biotechnological field such as sensing, nanomedicine, and bioelectronics technologies., This work was supported by The European Commission Program, FP7-OCEAN (613844) and MINECO (Spain; BIO2013–49464-EXP and RTC-2014–2619–7); Ministero dell’Università e della Ricerca Scientifica (Italy)—Industrial Research Project PON01_01966 EnerbioChem, funded in the frame of Operative National Programme Research and Competitiveness 2007–2013 D. D. Prot. n. 01/Ric. 18.1.2010; P.O.R. Campania FSE 2007–2013, Project CREMe. ICN2 acknowledges support from the Severo Ochoa Program (MINECO, Grant SEV-2013–0295).

We demonstrate how self-assembled monolayers of aromatic molecules on copper substrates can be converted into high-quality single-layer graphene using low-energy electron irradiation and subsequent annealing. We characterize this two-dimensional solid state transformation on the atomic scale and study the physical and chemical properties of the formed graphene sheets by complementary microscopic and spectroscopic techniques and by electrical transport measurements. As substrates we successfully use Cu(111) single crystals and the technologically relevant polycrystalline copper foils., Comment: 12 pages, 4 figures, supporting information