The present invention provides a new material and its manufacturing process to create improved binder-free composite materials having a network of carbon nanotubes (CNTs) and activated carbon (aC) particles in which one or more types of particles or fibers is embedded. The activated carbon particles are embedded in a network or matrix of single-walled or multiple-walled CNTs. The highly dispersed and entangled CNT network provides essential high electrical conductivity, mechanical strength and durability which provides for the free-standing and binder-free characteristics. The high aspect ratio of the entangled CNTs allow for the incorporation of micron sized particles within the network structure. The absence of binders, which block surface pores and thus decrease usable surface area, allows for maximum adsorption of desired materials onto the carbon's highly microporous surface. The composite materials may be made by filtering suspensions containing carbon nanotubes, particles or fibers of interest, or both carbon nanotubes and particles or fibers of interest. The particles may be silicon particles, activated carbon particles, particles of a lithium compound, any other particles, or a combination thereof.
The produced sheets can have a multitude of uses where high surface area, low electrical resistivity, low mass density and the chemical or electrochemical properties of carbon are desired. These applications include but are not limited to: batteries, fuel cells and electrochemical capacitor electrodes, water purification systems (capacitive deionization electrode, membrane filtration), hydrogen storage materials, gas purification, etc.