Superior sorption capacity and one-step reduction of Au(III) by a novel chitosan-based electrospun fiber mat: A cheap and simple technique

•A novel chitosan-based fiber mat was synthesized by electrospinning technique.•Sorption capacity of Au(III) by the fiber mat CS-Glu-Th reached 2.28 × 106 mg/kg.•Favorable sorption selectivity of Au(III) by the fiber mat CS-Glu-Th was achieved.•94.55% of sorbed Au(III) was directly reduced to Au(0) by C-N group on CS-Glu-Th.•The profit rate of Au(III) recovered vs. cost for CS-Glu-Th synthesis is about 22.0%.