A process for producing a unitary graphene material, comprising: (a) preparing a graphene oxide (GO) gel having GO molecules dissolved in a fluid medium wherein the GO molecules contain higher than 20% by weight of oxygen; (b) dispensing and depositing a layer of GO gel onto a surface of a substrate to form a layer of deposited GO gel thereon, wherein the dispensing and depositing procedure includes shear-induced thinning; (c) removing the fluid medium from the deposited GO gel to form a GO layer having an inter-plane spacing d002 of 0.4 nm to 1.2 nm as determined by X-ray diffraction; and (d) heat treating the GO layer to form the unitary graphene material at a heat treatment temperature higher than 100° C. to an extent that d002 is decreased to a value of 0.3354 nm to 0.4 nm and the oxygen content is decreased to less than 5% by weight.