Porous silica composite material as well as preparation method and application thereof

The invention relates to a porous silica composite material as well as a preparation method and application thereof. The method comprises the steps: in a reaction furnace, introducing a gaseous carbon source to perform gas phase coating on the SiOx powder material to obtain a silicon oxide C-SiOx containing a first carbon coating layer; carrying out heat treatment on the C-SiOx for 1-10 hours in an inert atmosphere at the temperature of 900-1150 DEG C, so that at least part of SiOx in the C-SiOx is subjected to self-oxidation-reduction reaction: 2SiOx = (2-x) Si + xSiO2; uniformly stirring a product subjected to heat treatment and a dispersing agent solution in a reaction container, adding a hydrofluoric acid aqueous solution with the mass concentration of 5-55% according to the molar ratio of C-SiOx to hydrofluoric acid of 1: 1-1: 8, and reacting for 1-10 hours under 100-1500r/m i n to obtain a silicon oxide P-C-SiOy which is of a porous structure and contains a first carbon coating layer, wherein y is great