Synthesis of Cu@NC/rGO Derived from Copper Phthalocyanine as an Advanced Anode for Hybrid Dual-Ion Capacitors

The composite material comprising copper phthalocyanine (CuPc) and graphene oxide (GO) is a novel functional material with broad application prospects in the field of electrochemistry. In this paper, a composite material consisting of copper coated with nitrogen-doped carbon supported on reduced graphene oxide (Cu@NC/rGO) was synthesized using CuPc/GO as the precursor through thermal treatment and carbonization processes. The porous Cu@NC/rGO composite not only provides abundant active sites but also constructs rapid ion transport pathways. Within the composite, Cu@NC nanoparticles act as effective electron transfer bridges, forming a continuous conductive network that reduces interfacial contact resistance. The hybrid dual-ion capacitor (HDIC) assembled with the Cu@NC/rGO composite material demonstrated outstanding cycling stability, achieving a discharge specific capacity of 328.6 mAh g -1 at a current density of 2.0 A g -1 after 4000 cycles. Density Functional Theory (DFT) calculations and electronic structure analysis revealed that the Cu@NC/rGO material exhibits the strongest adsorption capability toward EMIm + ions, with an adsorption energy as low as -299.02 kJ·mol -1 , accompanied by the most significant charge transfer. This work provides new design inspiration for the development of anode materials for HDIC.