Hydrothermal carbonaceous materials and MnO2 have been proved to be promising adsorbents to remove organic dyes from wastewater.In this study,flexible MnO2 loaded hydrothermal carbon-coated electrospun poly-acrylonitrile(AC/MnO2/PAN)fiber membranes were fabricated by a facile one-step hydrothermal method and activated by NaOH solution.The composite fibers exhibited large adsorption capacity toward cationic dyes and ex-cellent mechanical properties.The adsorption performance can be fitted well with pseudo-second-order model and Langmuir isotherm model.The maximum adsorption for methylene blue(MB),methyl violet(MV)and malachite green(MG)are 1173.27,1106.31 and 1129.89 mg/g,respectively,according to Langmuir fitting.The AC/MnO2/PAN fiber membrane also showed satisfactory performances for selective adsorption and recyclability.In addition,based on selective adsorption,the AC/MnO2/PAN fiber membranes that are repulsive to the anionic dye methyl orange(MO)can separate the MB/MO mixture solution by dynamic filtration.Thus,this work not only provides a facile strategy to fabricate large capacity adsorbents,but also demonstrates the potential applications in the dye wastewater treatment field.