Graphene far-infrared negative-oxygen-ion heating sheet and preparation method thereof

The invention provides a graphene far-infrared negative-oxygen-ion heating sheet. From a top to a bottom, the heating sheet successively includes a first negative-oxygen-ion layer, a first insulatinglayer, a graphene heating layer, a second insulating layer and a second negative-oxygen-ion layer which are mutually stacked. Edges of the first insulating layer and the second insulating layer are integrated into one body to form a first cavity accommodating the graphene heating layer. Distance between a peripheral edge of the graphene heating layer and a peripheral edge corresponding to the first cavity is 2-4 cm. Two electrodes are arranged on the graphene heating layer, and are used for connection with positive and negative poles of an external power source. The heating sheet has very goodinsulating performance, the heating sheet can release far-infrared rays, and can release negative oxygen ions, and air quality in a greenhouse is improved; and then plant root development and plant growth can be promoted, occ