Nickel hexacyanoferrate on nitrogen-rich CNTs: An efficient bi-functional catalyst for crystal violet removal and electrochemical urea oxidation

Herein, a novel material composed of nickel-iron Prussian blue (NFPB) incorporated on nitrogen-rich carbon nanotube (NFPB/N[sbnd]CNT) core/shell nanostructured is prepared by combining melamine and nitric acid with the subsequent thermal treatment (200–600 °C) of the as-synthesised N-rich CNTs and NFPB as a coating layer. This material exhibits excellent crystal violet (CV) removal from water and electrochemical urea oxidation reaction (UOR). The findings provide a simple method for efficiently modifying CNT bulk and surface. The NFPB/N[sbnd]CNT core/shell nanostructure removes 83 % CV in 5 min and achieves 99 % removal efficiency after 30 min, compared to 40 % and 21 % for N[sbnd]CNTs and bare CNTs. Additionally, it demonstrates excellent electrocatalytic activity in 1.0 M KOH and 0.33 M urea for the UOR, compared to bare CNTs. The high conformity of the coating (10–15 nm NFPB shell) and nitrogen-rich doping are responsible for the remarkable adsorption ability and electrochemical activity of CNT. This research is essential for developing environmentally acceptable materials for a more efficient bifunctional catalyst for removing organic dyes and electrochemical UOR from water.