Controlled fabrication of flexible graphene aerogels via naturally dried and its photocatalysis-persulfate activation for ciprofloxacin degradation under sunlight

Abstract

Materials for environmental purification should have not only the high purification efficiency, but also the character of mechanical strength, stabilized performance and no secondary pollution. Here, the flexible graphene aerogel (GA) was obtained via a controlled natural drying method combined with hydrothermal process. The effects of preparation conditions on GA, such as NH4•OH dose, H3BO3 dosage, ascorbic acid (VC) amount and GO concentration, were systematically explored. The prepared GA possessed outstanding adsorption property for organic liquid solvents (capacity achieved 307 times its own weight) and excellent physical features of flexible conductors, low density (3.4 mg/cm3), high porosity (95.4 %), mechanical stability (supports at least 1150 times its own weight), hydrophobicity (contact angle of 93°) and high energy density (0.477 mAh/cm2). Furthermore, the contribution of excellent light absorption, effective electron transfer, high surface area and CO bond made GA represent superior photocatalysis-persulfate activation performance for ciprofloxacin (CIP) degradation (85.5 %) for 60 min under sunlight. The removal rate of CIP still remained at 78.4 % after 5 cycle tests, indicating that GA possessed excellent stability. The flexible GA exhibited tremendous potential in environmental purification and flexible conductive material.