Graphene-based composite with high stable dispersion in ethanol.

In the last few years a lot of applicative research studies are focused on graphene, a 2D carbo-material with very particular physical features like electro-conductivity, thermo-conductivity, mechanical stability, and its particular aspect ratio with a high surface and a negligible thickness (1–3). For that features the spectra of possibilities to make a new application with this material, are big and grow time after time. In addition, with climate change, the focus of research to make new technologies greener and with less impact, on the environment, than now has moved to increase the study of that material and most researchers have focused their studies on the possibility to disperse that material in a green solvent with low boiling point. One problem with pristine Graphene is that it could be dispersed with high concentration only in polar aprotic solvent as n-methyl-2-pyrrolidone or Dimethyl formamide (4), a solvent with a high boiling point and with high toxicity for the humans and the environment. Usually for that reason is preferred to use the oxidized form of graphene GO, most easy to disperse, and reduce in rGO. The reduced form has the problem of having more defects on the surface than pristine graphene losing a part of the natural performance of the graphene. Another method studied is the use of a surfactant (5)or making nano-composite material with the use of polar polymer such as the PVP (6–8) has permitted to disperse of the material with a good concentration in water. This research has moved used to investigate how to make new composite graphene-based, easy to disperse in an organic polar solvent such as ethanol. We made an uncontrolled growth of polymer (ethyl maleate derivate) on the surface of the material, for making that we use the support of the microwave reactor that, with the particular characteristic of the graphene to be a radical initiator, permits the formation of different particles of polymer maleate based on the surface of the graphene. This material has good stability in ethanol and maintains that feature after a long time. That dispersion opens the possibility to make ink graphene-based or coating on other surfaces and other different applications with the fast removal of the solvent. At the same time the uncontrolled growing permit the removal of the composite with the heating of the material in an inert atmosphere to obtain pristine graphene with a low number of defects. Bibliography 1. Clancy AJ, Bayazit MK, Hodge SA, Skipper NT, Howard CA, Shaffer MSP. Charged Carbon Nanomaterials: Redox Chemistries of Fullerenes, Carbon Nanotubes, and Graphenes. Chem Rev. 2018;118(16):7363-7408. doi:10.1021/acs.chemrev.8b00128 2. Randviir EP, Brownson DAC, Banks CE. A decade of graphene research: Production, applications, and outlook. Mater Today. 2014;17(9):426-432. doi:10.1016/j.mattod.2014.06.001 3. Wei W, Qu X. Extraordinary physical properties of functionalized graphene. Small. 2012;8(14):2138-2151. doi:10.1002/smll.201200104 4. Vacacela Gomez C, Guevara M, Tene T, et al. The liquid exfoliation of graphene in polar solvents. Appl Surf Sci. 2021;546(December 2020):149046. doi:10.1016/j.apsusc.2021.149046 5. Wang S, Yi M, Shen Z, Zhang X, Ma S. Adding ethanol can effectively enhance the graphene concentration in water-surfactant solutions. RSC Adv. 2014;4(48):25374-25378. doi:10.1039/c4ra03345k 6. Laaksonen P, Kainlauri M, Laaksonen T, et al. Interfacial engineering by proteins: Exfoliation and functionalization of graphene by hydrophobins. Angew Chemie - Int Ed. 2010;49(29):4946-4949. doi:10.1002/anie.201001806 7. Perumal S, Lee HM, Cheong IW. High-concentration graphene dispersion stabilized by block copolymers in ethanol. J Colloid Interface Sci. 2017;497:359-367. doi:10.1016/j.jcis.2017.03.027 8. Wajid AS, Das S, Irin F, et al. Polymer-stabilized graphene dispersions at high concentrations in organic solvents for composite production. Carbon N Y. 2012;50(2):526-534. doi:10.1016/j.carbon.2011.09.00

Production of Graphene Stably Dispersible in Ethanol by Microwave Reaction

Graphene is a 2D carbon material with peculiar features such as high electrical conductivity, high thermal conductivity, mechanical stability, and a high ratio between surface and thickness. Applications are continuously growing, and the possibility of dispersing graphene in low-boiling green solvents could reduce its global environmental impact. Pristine graphene can be dispersed in high concentration only in polar aprotic solvents that usually have high boiling points and high toxicity. For this reason, the oxidized form of graphene is always used, as it is easier to disperse and to subsequently reduce to reduced graphene oxide. However, compared to pristine graphene, reduced graphene oxide has more defects and has inferior properties respect to graphene. In this work, the polymerization of (diethyl maleate derivate) on graphene obtained by sonication was performed in a microwave reactor. The obtained material has good stability in ethanol even after a long period of time, therefore, it can be used to deposit graphene by mass production of inks or by casting and easy removal of the solvent. The thermal annealing by heating at 300–400 ◦C in inert atmosphere allows the removal of the polymer to obtain pristine graphene with a low number of defects

The Virtuous CO 2

It is not the first time in human history, nor will it be the last for that matter, that a collective problem calls for a collective response. Climate change fueled by greenhouse emissions affects humankind alike. Despite the disagreement among policymakers and scientists on the severity of the issue, the truth is that the problem remains. A broad look at different technologies being used today in different fields has led to the idea of bringing them together in an attempt to offer a viable solution to reducing anthropogenic CO2.The following paper describes how the nanotechnologies, available or soon to be available, would make CO2 capture, cache, and conversion (coined the three Cs) a valid way for achieving a more sustainable energy society. Authors also set out to highlight with this work how knowledge transfer is instrumental in the development of technology and how methodical assessment of crossovers can expedite research when time plays against us

Large expert-curated database for benchmarking document similarity detection in biomedical literature search

Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe

Graphene based mixed matrix membranes for CO2 separation

L'abstract è presente nell'allegato / the abstract is in the attachmen

Acid-catalyzed reaction of 2-hydroxycyclobutanone with benzylic alcohols

The acid-promoted syntheses of 2-(benzyloxy)cyclobutanones and bis(benzyloxy)dioxatricyclo decanes were achieved starting from 2-hydroxycyclobutanone and variously functionalized benzyl alcohols. The reaction sequences afforded the desired products in good to high yields and in a solvent-dependent chemoselective fashion

Acid-catalyzed synthesis of functionalized arylthio cyclopropane carbaldehydes and ketones

A general strategy for the synthesis of arylthio cyclopropyl carbaldehydes and ketones via a Brønsted acid catalyzed arylthiol addition/ring contraction reaction sequence has been exploited. The procedure led to a wide panel of cyclopropyl carbaldehydes in generally high yields and with broad substrate scope. Mechanistic aspects and synthetic applications of this procedure were investigated

Production of Graphene Stably Dispersible in Ethanol by Microwave Reaction

Graphene is a 2D carbon material with peculiar features such as high electrical conductivity, high thermal conductivity, mechanical stability, and a high ratio between surface and thickness. Applications are continuously growing, and the possibility of dispersing graphene in low-boiling green solvents could reduce its global environmental impact. Pristine graphene can be dispersed in high concentration only in polar aprotic solvents that usually have high boiling points and high toxicity. For this reason, the oxidized form of graphene is always used, as it is easier to disperse and to subsequently reduce to reduced graphene oxide. However, compared to pristine graphene, reduced graphene oxide has more defects and has inferior properties respect to graphene. In this work, the polymerization of (diethyl maleate derivate) on graphene obtained by sonication was performed in a microwave reactor. The obtained material has good stability in ethanol even after a long period of time, therefore, it can be used to deposit graphene by mass production of inks or by casting and easy removal of the solvent. The thermal annealing by heating at 300–400 °C in inert atmosphere allows the removal of the polymer to obtain pristine graphene with a low number of defects

Ionic Liquids-Polymer of Intrinsic Microporosity (PIMs) Blend Membranes for CO2 Separation

Membranes with high CO2 solubility are essential for developing a separation technology with low carbon footprint. To this end, physical blend membranes of [BMIM][Ac] and [BMIM][Succ] as Ionic Liquids (ILs) and PIM-1 as the polymer were prepared trying to combine the high permeability properties of PIM-1 with the high CO2 solubility of the chosen ILs. Membranes with a PIM-1/[BMIM][Ac] 4/1 ratio nearly double their CO2 solubility at 0.8 bar (0.86 cm3 (STP)/cm3 cmHg), while other ratios still maintain similar solubilities to PIM-1 (0.47 cm3 (STP)/cm3 cmHg). Moreover, CO2 permeability of PIM-1/[BMIM][Ac] blended membranes were between 1050 and 2090 Barrer for 2/1 and 10/1 ratio, lower than PIM-1 membrane, but still highly permeable. The here presented self-standing and mechanically resistant blend membranes have yet a lower permeability compared to PIM-1 yet an improved CO2 solubility, which eventually will translate in higher CO2/N2 selectivity. These promising preliminary results will allow us to select and optimize the best performing PIM-1/ILs blends to develop outstanding membranes for an improved gas separation technology