METHOD FOR PREPARING FILMS OF GRAPHENE OR GRAPHENE MATERIALS ON NON-METALLIC SUBSTRATES

The present invention describes a method for the preparation of films of graphene or of a graphene material by means of biopolymer carbonization. The method comprises the following steps: - preparation of an aqueous solution of a non-crystallizable biopolymer or a derivative of said biopolymer at a suitable pH; - coating the substrate with the aqueous biopolymer solution prepared in the preceding step by means of immersion of the substrate in said solution, or by using the spin-coating technique; - conditioning the aqueous biopolymer solution by means of a hydrothermal process consisting in subjecting the coated surface to a flow of nitrogen or argon saturated with water vapour at a temperature of between 100 and 250°C for a period of time of between 30 min and a number of hours; - and thermal decomposition of the biopolymer deposited on the substrate in the absence of oxygen at temperatures below 1200°C. The preferred biopolymers in the present invention include polysaccharides, such as alginate, chitosan, starch and carraghenates, and derivatives thereof. Owing to the properties of the graphene, the substrates coated by means of this process can be used in the microelectronic and photovoltaic industries as components for solar cells, etc.

46173009

WO

2013