Tuning the pore architectures of hierarchically porous carbons from high internal phase emulsion template by polyaniline-coated CNTs

Abstract

The work reported the preparation of hierarchically porous carbons (HPCs) with adjustable pore architectures using high internal phase emulsion (HIPE) template with the presence of polyaniline-coated carbon nanotubes (PANI-CNTs). PANI-CNTs were obtained via in situ polymerization of aniline in CNT suspension as confirmed by scanning electron microscope (SEM) and thermogravimetric analysis (TGA). Porous polydivinylbenzene (PDVB) monoliths were prepared by polymerizing the continuous phase of HIPE with PANI-CNTs dispersed in the internal phase. After carbonization and activation, HPCs with variable pore architectures were obtained. As observed by SEM, the PANI-CNTs showed notable influence on the pore architectures of PDVBs and HPCs. The void size of PDVB precursor reduced with the increase of the mass ratio of PANI to CNT, as well as the content of PANI-CNTs. Nitrogen adsorption/desorption measurements indicated the coexistence of mesopores and micropores, namely, hierarchical pores. The specific surface area (SSA) of HPC increased along with the content of PANI-CNTs from 1893 to 2392 m2/g. The capability of HPCs as the electrode material of supercapacitor was evaluated via electrochemical tests. The results indicated that the HPC with optimized pore architecture showed a higher specific capacitance (168.6 F/g) than the contrast sample (130.9 F/g) at 1 A/g. The better capacitance performance of HPC obtained with the presence of PANI-CNTs could be attributed to the reasonable hierarchical pores, higher SSA, and higher graphitization degree.