ZIF-67-derived CoP as a single photocatalyst exhibited extremely excellent H2 evolution performance in Eosin Y sensitization system. Specifically, both Co3O4 and CoP polyhedron can be derived by ZIF-67 as a precursor in different atmosphere. Interestingly, ZIF-67-derived Co3O4 is a typical p-type semiconductor but CoP is an n-type semiconductor. Therefore, one-step construction of Co3O4@CoP p-n heterojunction was successfully implemented firstly in this work, that is, ZIF-67 polyhedron was transformed into Co3O4@CoP polyhedron that Co3O4 co-arranged with CoP species. More importantly, the ZIF-67-derived Co3O4@CoP p-n heterojunction photocatalyst exhibits more excellent photoctalytic water splitting properties than ZIF-67-derived CoP and Co3O4 as well as previous-best catalysts under identical conditions because of multi-action mechanism synergy. Additionally, the action mechanism about metal phosphides in H2 evolution reaction is revealed more thoroughly by the assistance of DFT and Zeta potential analysis