Nitrogen and oxygen co-doping carbon microspheres by a sustainable route for fast sodium-ion batteries

Heteroatom-doping has been regarded as an effective strategy to regulate the Na storage performance of carbon materials. In this paper, N and O dual-doped carbon microspheres (NO-CS) from the rinds of corn stalks have been fabricated via a tailored carbonization and solution doping route. NO-CS reveals both high O (15.6 at.%), N (6.4 at.%) contents and high specific surface area (746.48m(2) g(-1)). The NO-CS derived carbon anode shows tremendous reversible capacity, rate capability and cycling stability, e.g. 270 mAh g(-1) over 200 cycles at 50 mA g(-1), 130 mAh g(-1) over 3500 cycles at 5 A g(-1). The superior Na storage property may due to the abundant porosity and dual-doping that boost fast ion adsorption at the graphene layer defects and nitrogen oxygen moiety of carbon. Scalable and cost-effective synthesis route with outstanding Na storage performance makes NO-CS a competitive anode material for Na-ion batteries. (c) 2019 Elsevier Ltd. All rights reserved.