Coupled electrostatic induction strategy toward polyaniline-derived hard carbon with uniformly microporous boosts high-rate sodium storage

Constructing a uniform and controllable hard carbon anode with suitable micropores can effectively improve the overall sodium storage performance. Herein, an electrostatic induction strategy was used to change the structure of micelles by adding surfactant content to form polyaniline (PANI) with different morphologies. The presented synthesis method is characterized by the introduction of oppositely charged surfactants to induce rapid nucleation and the formation of foams with small pore sizes, which are then transformed into homogeneous microcellular pores by high-temperature carbonization. Thus, the microporous structures in hard carbon anode provide excellent electrochemical storage sites for sodium ion storage. As a consequence, the sodium dodecyl benzene sulfonate (SDBS) electrostatic induced PANI-derived hard carbon (SD-HC) showed a uniform pore structure with low surface area (14.54 m² g⁻¹) and uniform micropores (1.54 nm), which used as an anode material for sodium storage can provided high reversible capacity of 282.4 mAh g⁻¹ at 50 mA/g, excellent rate performance (196 mAh g⁻¹ at 5 A/g) and cycling stability (93.3 % capacity retention after 1000 cycles at 1 A/g). This simple and efficient synthesis strategy provides an effective guide for the design of nanostructures for the preparation of similar functional polymeric materials.