Electrode designs based on sheet racks and blocks w ith multi-diffuse groove spaces and enriched active sites and scales would promote the commercial applications of electroactive materials. We report a facile one-pot hydrothermal approach to synthesize mesoscopic porous Co 3 O 4 or hybrid graphene (GO)/Co 3 O 4 sheet-on-sheet racks and blocks. Three basic types of sheet scalability racks can be built in vertical and non-stacked edge orientations, such as neat micro/nano-groove rooms, butterfly wing scales, and wall groves, leading to highly exposed surface converges and sites. In particular, the stacked S-GO/Co 3 O 4 sheet-on-sheet blocks can be oriented in vertical tower buildings. The atomic structures of the developed Co 3 O 4 catalysts were dominant along the highly dense {112/111} interfaces and single crystal {111} and {112} facets. The electrochemical performance of the mesoscopic porous Co 3 O 4 catalyst toward alcohol electrooxidation was evaluated in alkaline conditions. The mesoscopic hybrid GO/Co 3 O 4 racks revealed superior catalytic activity in terms of oxidation currents and onset potentials, indicating the effect of the synergetic role of active Co 3+ sites along the densely exposed {112} facets, graphene counterparts, and hierarchically non-stacked sheet racks on the electroactive functionality. Results indicate that the mesoscopic GO/Co 3 O 4 sheet catalyst is suitable for highly efficient electrochemical reactions.