Ball-flower-like hierarchically porous carbons via a "work-in-tandem" strategy for effective energy storage and CO2 capture

Benefiting from the unique structural features, ball -flower -shaped hierarchically porous carbons have drawn increasing attention as an emerging porous carbon material for energy and environment applications. Unfortunately, developing a simple and efficient strategy to synthesize flower-like hierarchically porous carbons is still challenging. Herein, we propose an innovative "work -in -tandem" pathway for the effective synthesis of hierarchically porous carbons nanoflower (HPCNF). ZnO nanoparticles play a tandem role, which work as templates for replicating the flower-like superstructure at the beginning and then successively function as porogen precursor for generating hierarchical pores on the petals by the in situ -converted activating agent. The formation mechanism of ball -flower-like morphology with superior hierarchical porosity is ascertained. The resultant materials possess relatively uniform flower-like morphology, high surface area, interconnected hierarchical porosity and suitable surface functionalization. Importantly, the hierarchical porosity with different micro-meso-macropore ratios can be readily tailored by tuning the ZnO nanoparticles dosage without sacrificing the ball -flower-like morphology. As the electrodes for energy storage, HPCNF-x exhibit the outstanding electrochemical supercapacitive behaviors. Meanwhile, as the CO2 adsorbents, HPCNF-x also show the satisfactory CO2 capture property. This work provides an innovative and effective synthetic method for the rational engineering of hierarchical porous materials with specific morphology towards a variety of potential energy and environmental applications.