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Various nano-sized semiconductors combined with nobel-metal have been widely explored to develop high efficient photocatalytic materials for hydrogen production.Considering limited metal resource in the world and potential harmful to environment and health,graphene has been chosen as a potential alternate of nobel-metal cocatalyst.However,up to now,there are few examples of graphene assisted photocatalyst catching up or surpassing the performace of the noble-metal assisted photocatalyst.That makes graphene is suspected to be an effective cocatalyst to instead of noble-metals.To clear the puzzles,the epitaxial graphene(EG)is chosen to study the possibility as a high efficient cocatalyst to splitting water for hydrogen evolution,where EG is in-situ epitaxial growth on surface of micrometer-sized SiC particles forming a core-shell heterojuction with perfect hetero-interface and satisfied graphene quality.In this paradigm,it is demonstrated that a high efficient hydrogen evolution rate about 0.5 mmol g-1 h-1 is achieved by the graphene covered SiC powder(GCSP)under a 0.5 AM 1.5 simulated solar irradiation,which exceeded the corresponding ones observed on pristine SiC particles by more than 33 times and on the optimized Pt-decorated SiC particles by near 4 times.As we known,this is the highest enhancement factor of graphene as a sole cocatalyst and provides a solid evidence that graphene is superior to the noble-metal as cocatalyst.The quantum efficiency for H2 evolution is estimated to be about 5.6%under a 380 nm monochrome laser irradiation.The abnormal high hydrogen evolution ability on the micrometer sized graphene/SiC core-sell heterojunction is ascriberd to the perfect combination of the quality core-shell interface,suitable band structure configuration between the graphene and SiC,and the advanced carrier transfer properties of graphene as well as their synergetic effects.Our paradigm demonstrates that graphene is qualified to replace noble-metal as a cocatalyst and the GCSP is a potential eco-friendly material applicable for high efficient H2 evolution.