Metal-Free Carbonaceous Materials as Promising Heterogeneous Catalysts

Metal-free carbonaceous materials have attracted considerable interests as heterogeneous catalysts owing to their superior physiochemical properties over metal-based catalysts, such as low cost, no pollution, chemical and thermal stabilities, as well as readily tailorable porous structure and surface chemistry. This review article provides an overview of the fundamentals and recent advances in the field of metal-free carbon catalysts, including graphenes, carbon nanotubes, mesoporous carbons, graphitic carbon nitrides, and related composites. Special focus is placed on their controllable preparation and applications in gas phase, liquid phase, electrochemical, and photocatalytic reactions, as well as defect and surface chemistry related catalytic activities of carbon materials. Some perspectives are highlighted on the development of more efficient metal-free carbonaceous catalysts featuring high stability, low cost, optimized structures, and enhanced performance, which are the key factors to accelerate the designed preparation and commercialization of carbocatalysts.