Additional information: Use policyThe full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-prot purposes provided that:• a full bibliographic reference is made to the original source • a link is made to the metadata record in DRO • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders.Please consult the full DRO policy for further details. Their growth and mechanical interlocking over time are the most significant factors in shaping the material properties of concrete. The outstanding chemical and physical properties of nanomaterials provide the most efficient enhancement for the internal matrix of concrete, and recent progress in nanomodification of cement composite materials has enabled applications in structural reinforcement, reduction of environmental pollution, [2] and production of self-cleaning materials. [3] Previous studies [4][5][6][7][8][9][10] have largely focused on the incorporation of nanomaterials in cement. These include the incorporation of carbon nanotubes (CNTs) [7] and graphene oxide (GO) [4,5] in cement which resulted in a 50% (for CNT) and a 33% (for GO) improvement of the compressive strength, while industrial-grade thin graphite platelets (100 nm thickness) [6] were shown to improve the thermal conductivity. However, these findings do not extend directly to concrete, as the addition of sand and aggregate changes the physico-mechanical behavior of the material. Moreover, to date the role of atomically thin materials on nanoengineering of concrete is yet to be explored, and this holds the promise to change the landscape of construction materials leading to a more sustainable urbanization with lower carbon foot print and more resilient constructions against natural disasters.Here we report innovative few-atoms-thin graphene-enabled nanoengineered multifunctional concrete composites which display an unprecedented range of enhanced properties compared to standard concrete. We demonstrate an extraordinary increase of up to 146% in the compressive strength, up to 79.5% in the flexural one, and a decrease in the maximum displacement due to compressive loading by 78%. At the same Nanoegineered Concrete

self-powered electronics for which novel high-performance materials and low-cost fabrication processes are highly sought. Graphene, which exhibits remarkably high specific surface area, thermal conductivity, current density, transparency, and impermeability, [1] is an ideally suited system for exploring conceptually novel flexible electronics including energy harvesting devices. [2] An easy and scalable approach for graphene preparation is the liquid-phase exfoliation of chemically functionalized graphite, such as graphite oxide or graphite intercalated compounds, which allows the separation of the bulk material into individual atomically thin layers in a liquid medium to produce graphene suspensions. However, there are several issues associated with the films deposited from such suspensions, especially those comprising graphene oxide (GO): they are insulating and need to be converted into reduced graphene oxide (rGO) through harsh chemical or thermal processes, [3] which creates defects in the crystallographic structure of graphene, leading to poor electronic performance. Alternatively, pristine graphite (PG) can be directly exfoliated by various techniques such as ball or three-roll milling, sonication, and high-shear mixing to obtain graphene suspensions. [4,5] Such suspensions are stabilized by using organic solvents, [6] or surfactants to prevent reaggregation of the graphene flakes. [7] In particular, PG exfoliation by highshear mixing leads to a significant improvement in the quality of graphene, when compared with other exfoliation methods, and allows the production of more than 100 L h −1 of defect-free graphene water-based suspension. [5,8] Despite the recent developments in the production of graphene suspensions, the integration of high-quality graphene films obtained from water-based exfoliation of PG in emerging applications, such as flexible electronics, is lagging behind. Specifically, emerging and integrating technologies of water-based exfoliation of PG for haversting human energy that convert mechanical energy into electricity using various effects are still in its infacty, and more research is needed to develop and implement triboelectric nanogenerators (TENGs) as self-charging devices for flexible and wearable electronics. This is due to several issues associated with the deposition Wearable technologies are driving current research efforts to self-powered electronics, for which novel high-performance materials such as graphene and low-cost fabrication processes are highly sought.The integration of highquality graphene films obtained from scalable water processing approaches in emerging applications for flexible and wearable electronics is demonstrated. A novel method for the assembly of shear exfoliated graphene in water, comprising a direct transfer process assisted by evaporation of isopropyl alcohol is developed. It is shown that graphene films can be easily transferred to any target substrate such as paper, flexible polymeric sheets and fibers, glass, and Si substrates. By combining gra...

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We modified single- and few-layer nano-sized graphene films deposited by pulsed laser deposition (PLD) on ∼300-nm-thick SiO2/Si substrates. The samples were irradiated by a UVC lamp (wavelength of 254 nm) for 15 and 30 minutes in air atmosphere. The light was directed almost parallel (about 2 - 2.5 arcdeg declination angle) to the films’ surface. The influence of the modification was evaluated by ellipsometry and X-ray photoelectron and Raman spectroscopies. The results showed that the irradiation caused an increase of the C-O/C-OH bond and a decrease or the complete disappearance of the -C=O/-COOH bond. The structural quality of the graphene films was improved moderately after a 15-min UVC treatment.