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

摘要

The present invention describes a method for the preparation of graphene or graphenic material films by the carbonization of biopolymers. The method comprises the following stages:
- preparation of an aqueous solution of a non-crystallizable water-soluble biopolymer or a derivative of said biopolymer at the suitable pH,
- coating of the substrate with the aqueous solution of the biopolymer prepared in the previous stage by immersion of the substrate in said solution or by using the spin coating technique,
- conditioning of the aqueous solution of the biopolymer by means of a hydrothermal process consisting of subjecting the coated surface to a flow of nitrogen saturated with water vapor at the temperature of between 100 and 250 °C for a time between 30 minutes and several hours,
- thermal decomposition of the biopolymer deposited on the substrate in the absence of oxygen at temperatures below 1200 °C. Among the biopolymers preferred in the present invention there are polysaccharides such as alginate, chitosan, starch and carragenates and derivatives thereof. Due to the properties of graphene, the substrates coated by this process have application in the industry of microelectronics, photovoltaics, as components of solar cells, etc..