The method of the present disclosure is directed towards the formation of a three-dimensional carbon structure and includes the steps of adding a radical initiator to an amount of carbon starting material, forming a mixture, placing the mixture in a mold, maintaining the mixture and the mold at an elevated temperature for a period of time to form a thermally cross-linked molded mixture and removing the thermally cross-linked molded mixture from the mold. The disclosure also includes a three-dimensional carbon structure, with that structure including a thermally cross-linked carbon base material in a predetermined formation.