Scheme 1. Schematic illustration of the synthetic process for the attainment of nanoporous carbon–PANI core–shell nanocomposite materials, starting from the rhombic dodecahedron ZIF-8. For the preparation of nanoporous carbon, ZIF-8 was carbonized and Zn was removed by washing with HF. The SEM images of the bare carbon and carbon–PANI nanocomposite are as shown. The scale bars are 500 nm in length. The PANI nanorods were grown on nanoporous carbon and the lengths of the nanorods were controlled by the polymerization time.