▎ 摘　　要

A new composite electrode with porous interconnected nano-dendritic structures was prepared by electro-chemical co-deposition of graphene oxide and polypyrrole (GO-PPy) on a copper-nickel foam (CNF) substrate, and used for the electrosorption of Rhodamine B (RhB). The physical properties of the electrode were systematically characterized by a scanning electron microscope (equipped with energy-dispersive X-ray), X-ray diffraction, X-ray photoelectron spectroscopy and nitrogen adsorption/desorption. The operating conditions for electrosorption, i.e. electrolyte concentrations, applied potentials and pH, were investigated. The experimental data were fitted by Langmuir and Freundlich isotherms. Meanwhile, pseudo-first-order, pseudo-second-order and intra-particle pore diffusion models were used to investigate the adsorption kinetics. The results indicated that the electrosorption of RhB fitted Langmuir isotherm with q(m) = 416.7 mg/g and followed pseudo-second order kinetics. The adsorption capacity and adsorption rate of RhB on the GO-PPy@CNF electrode (270.3 mg/g and 3.762 mg/(g min)) were significantly higher than those on the CNF electrode (98.04 mg/g and 0.6614 mg/(g min)). This improved electrosorption of RhB on the composite electrode might be attributed to its porous interconnected nano-dendritic structure, which could provide more adsorption sites and abundant functional groups of GO-PPy. This work provided an environmentally friendly and economical technology for the RhB removal.