Advances in Subcritical Hydro-/Solvothermal Processing of Graphene Materials.

International audienceMany promising graphene-based materials are kept away from mainstream applications due to problems of scalability and environmental concerns in their processing. Hydro-/solvothermal techniques overwhelmingly satisfy both the aforementioned criteria, and have matured as alternatives to wet-chemical methods with advances made over the past few decades. The insolubility of graphene in many solvents poses considerable difficulties in their processing. In this context hydro-/solvothermal techniques present an ideal opportunity for processing of graphenic materials with their versatility in manipulating the physical and thermodynamic properties of the solvent. The flexibility in hydro-/solvothermal techniques for manipulation of solvent composition, temperature and pressure provides numerous handles to manipulate graphene-based materials during synthesis. This review provides a comprehensive look at the subcritical hydro-/solvothermal synthesis of graphene-based functional materials and their applications. Several key synthetic strategies governing the morphology and properties of the products such as temperature, pressure, and solvent effects are elaborated. Advances in the synthesis, doping, and functionalization of graphene in hydro-/solvothermal media are highlighted together with our perspectives in the field

Advances in subcritical hydro-/solvothermal processing of graphen materials

Many promising graphene-based materials are kept away from mainstream applications due to problems of scalability and environmental concerns in their processing. Hydro-/solvothermal techniques overwhelmingly satisfy both the aforementioned criteria, and have matured as alternatives to wet-chemical methods with advances made over the past few decades. The insolubility of graphene in many solvents poses considerable difficulties in their processing. In this context hydro-/solvothermal techniques present an ideal opportunity for processing of graphenic materials with their versatility in manipulating the physical and thermodynamic properties of the solvent. The flexibility in hydro-/solvothermal techniques for manipulation of solvent composition, temperature and pressure provides numerous handles to manipulate graphene-based materials during synthesis. This review provides a comprehensive look at the subcritical hydro-/solvothermal synthesis of graphene-based functional materials and their applications. Several key synthetic strategies governing the morphology and properties of the products such as temperature, pressure, and solvent effects are elaborated. Advances in the synthesis, doping, and functionalization of graphene in hydro-/solvothermal media are highlighted together with our perspectives in the field.Initiative d'excellence de l'Université de Bordeau

Advances in subcritical hydro-/solvothermal processing of graphen materials

Many promising graphene-based materials are kept away from mainstream applications due to problems of scalability and environmental concerns in their processing. Hydro-/solvothermal techniques overwhelmingly satisfy both the aforementioned criteria, and have matured as alternatives to wet-chemical methods with advances made over the past few decades. The insolubility of graphene in many solvents poses considerable difficulties in their processing. In this context hydro-/solvothermal techniques present an ideal opportunity for processing of graphenic materials with their versatility in manipulating the physical and thermodynamic properties of the solvent. The flexibility in hydro-/solvothermal techniques for manipulation of solvent composition, temperature and pressure provides numerous handles to manipulate graphene-based materials during synthesis. This review provides a comprehensive look at the subcritical hydro-/solvothermal synthesis of graphene-based functional materials and their applications. Several key synthetic strategies governing the morphology and properties of the products such as temperature, pressure, and solvent effects are elaborated. Advances in the synthesis, doping, and functionalization of graphene in hydro-/solvothermal media are highlighted together with our perspectives in the field.Initiative d'excellence de l'Université de Bordeau

An effective in situ reduction strategy assisted by supercritical fluids for the preparation of graphene - polymer composites

The chemical/thermal in situ reduction of graphene oxide (GO) in GO-polymer composite is consistently challenged by the presence of undesirable chemical residues/temperature degradation restriction of the polymer. In order to tackle this problem, an effective in situ supercritical fluid reduction strategy comprising of supercritical CO2 and ethanol binary system under N2 atmosphere was developed by stepwise comparison of different reduction methods for graphene oxide-polyvinyl alcohol (GO-PVA) composite films. The resulting rGO-PVA composite films comprising of 10 wt% rGO showed an electrical conductivity of 51.7 S/m-and Young's modulus of 3.1 GPa. Different weight loadings of GO in the polymer composite films were found to affect the electrical and mechanical properties of the resulting rGO-polymer films. The in situ supercritical fluid reduction strategy was demonstrated further for successfully obtaining rGO-polyethylene glycol films (rGO-PEG) and rGO-PVA fiber.Initiative d'excellence de l'Université de Bordeau