Triton X-100-Assited Electropolymerization to Prepare Poly(1,5-diaminonaphthalene- <i>o</i> -phenylenediamine) as an Electrode Material for Charge Storage

Aromatic amines serve as monomers to produce conducting polymers by electropolymerization with good energy storage properties. However, their poor water solubility limits their electropolymerization processes. The copolymer of 1,5-diaminonaphthalene and <i>o</i>-phenylenediamine (PDAN-<i>co</i>-oPD) was synthesized for the first time using Triton X-100-assisted electropolymerization on a carbon cloth substrate. The energy storage mechanism of the material was investigated using X-ray photoelectron spectroscopy and scanning electron microscopy, where both Zn²⁺ and H⁺ were involved in the charge storage process in H₂SO₄ and ZnSO₄ aqueous electrolytes. PDAN-<i>co</i>-oPD delivers specific capacities of 160.31 and 307.37 mAh g^-1 in 1 M H₂SO₄ and 1 M ZnSO₄ at 0.5 A g^-1, respectively, along with high stability (88.5 and 94.7% capacity retention at 10 A g^-1 after 3000 cycles in 1 M H₂SO₄ and 1 M ZnSO₄, respectively). In addition, an aqueous zinc-ion electrochemical energy storage device was assembled, which exhibits a specific energy of 68.06 Wh kg^-1 at a charging and discharging rate of 0.5 A g^-1. These results show that PDAN-<i>co</i>-oPD can serve as an energy storage material to store charge in aqueous electrolytes.