Synthèse et caractérisation de nanocomposites d'argile et de graphène formés à partir de précurseurs organiques

Abstract

The clay minerals are potential catalysts for the formation of graphene from organic precursors, such as sucrose. Clays are abundant, safe and economic for the formation of graphene. The main objective of this paper is to demonstrate that it is possible to synthesize a hybrid material containing clay and graphene. The preparation of these carbonaceous materials based in clay (bentonite and cloisite) and sucrose was carried out using two methods. The first method is conducted in three steps: 1) period of contact between the clay and the carbon source in a wet environment, 2) infiltration of the carbonaceous material and processing the microwave oven, 3) heating to 750° C under nitrogen for carbon materials. Against by the second method was made in two steps, without microwave, and with an increased carbon source (sucrose and alginate). The characterization of the material allowed following the transformation reactions of the carbon source to graphene. FTIR and Raman spectroscopy, thermogravimetric analysis (TGA), the specific surface area (BET method) and the scanning electron microscope (SEM) were used for characterization. The electrical conductivity was measured by a spectrometer and dielectric function of the pressure applied with a multimeter. The material produced was incorporated into a matrix with a low-density polyethylene (LDPE) to have a polymer with specific characteristics. The thermal conductivity was then measured according to ASTM E1530. The sample made with the second method with a proportion of bentonite for 5 proportions of sucrose (M2 B1: S5) indicates the possibility of producing graphene materials from natural resources. The surface area increased significantly from (75.88 m2/g) for untreated bentonite to (139.76 m2/g) for the sample M2 B1: S5. A significant increase of the conductivity by pressure was measured (95.3 S/m under a pressure of 6.5 MPa as compared to 1.45*10-3 S /m of bentonite). The thermal conductivity in low-density polyethylene at a concentration 10% additive was 0.332 W/m.K, as compared to 0.279 W/m.K for only bentonite. Possible applications include sensors and actuators by pressure.

Date	16 Dec 2016
Original language	French
Awarding Institution	École de technologie supérieure
Supervisor	Claudiane Ouellet-Plamondon (Supervisor)