Formation of a uniform interface between the carbon precursor and the selected template is critical for preparing high-quality nanoporous carbons. It can be accomplished by various templating procedures but still remains a challenge, especially for microporous carbons. A new strategy to fabricate well-defined microporous carbon nanosphere (MCNS) materials via molecular-scale interfacial engineering using an organic/inorganic hybrid molecule as the building block was designed. A commercially available octaphenyl polyhedral oligomeric silsesquioxane was selected as such a building block and transformed into the MCNS products via cross-linking of organic components, followed by carbonization, and subsequent removal of monodispersed silica domains, surrounded by molecular-scale carbon/silica interfaces. The obtained MCNS materials exhibit very large surface area (e.g., 2264 m(2)/g) and fast and selective sorption, and thus demonstrate excellent adsorption and supercapacitance properties. These findings could provide a new benchmark for preparing well-defined nanoporous carbons for various applications.