Engineering hierarchically porous carbon nanorods electrode materials for high performance zinc ion hybrid supercapacitors

Abstract

Well-defined carbon materials with tailored unique pore structure are crucial to develop advanced zinc ion hybrid supercapacitors (ZIHCs), but effective synthesis is still a challenge. Herein, hierarchically porous carbon nanorods (HPCNs) are successfully synthesized by Pluronic P123 (PEO20PPO70PEO20) mediated dynamic dual template method that tetraethylsiloxane (TEOS) and sucrose are adopted as silicon (Si) and carbon (C) precursors, respectively. During synthesis, the rod-like organic mesomorphous complexes are generated by self-assembly of cetyltrimethyl ammonium/poly-(acrylic acid) (CTAB/PAA) under the assistance of Pluronic P123 as dynamic soft templates and in-situ formed silica particles as hard templates. The synthesized HPCNs have uniform rod-like morphology, high surface area and notable specific capacity. Furthermore, the HPCNs are activated to afford AHPCNs with enriched micropores and increased surface area of 905 m2 g−1. Consequently, ZIHCs with the AHPCNs as cathode display attractive electrochemical performances including large capacity (157.1 mAh g−1 at 0.1 A g−1), exceptional rate performance (110.3 mAh g−1 at 20 A g−1), high energy density (125.7 Wh kg−1) and power density (16 kW kg−1). Moreover, ZIHCs demonstrated brilliant capacity retention of 100% even after 10,000 cycles at 5 A g−1. Our work presents an effective approach for controllable engineering of hierarchically porous carbon nanorod materials. Meanwhile, it also offers theoretical and technical support to develop advanced zinc ion capacitor energy storage devices.