A Visually Observable Copper Ion Adsorption Membrane by Electrospinning Combined with Copper Ion Probe

Heavy metal copper ion pollution has enormously threatened ecosystem and public health. So, materials for detecting and adsorbing copper ions (Cu 2+ ) still remains challenging. Electrospinning nanomaterials have good application prospects in the field of water treatment because of its high specific surface area, high porosity and three-dimensional structure. Here, a visualized chitosan/polyacrylonitrile (CS/PAN) nanofiber membrane (NFM) was prepared via the amination modification of the electrospinning membrane and the doping of Cu 2+ fluorescent probe to adsorb Cu 2+ . The effect of membrane absorbs Cu 2+ in water was studied from the aspects of initial Cu 2+ concentration, PH and adsorption time. It was found that when the pH value of the Cu 2+ environment is 5–6, the weight gain rate of aminated nanofiber membrane is 46 %, and the adsorption time is 90 minutes, the adsorption capacity of the NFM can reach 164.3 mg/g. Then, rhodamine hydrazide derivatives were used as fluorescent Cu 2+ probes, which were added to the spinning solution to prepare new NFM to achieve selective recognition of Cu 2+ . The membrane can be used multiple times and can achieve gradient color development of different concentrations of Cu 2+ , and the detection limit can reach 10 −8 M.