Green conversion of bamboo chips into high-performance phenol adsorbent and supercapacitor electrodes by simultaneous activation and nitrogen doping

Abstract Nitrogen doping is one of the most promising approaches for improving the properties of carbon materials. Here, we reported a simple and effective method for the preparation of nanoporous nitrogen-doped carbonaceous material for liquid phase adsorbents and supercapacitor electrodes. In this method, the target carbonaceous material (biochar) was produced by one-step pyrolysis and activation of bamboo chips under the ammonia atmosphere. Two green activation reagents (K2C2O4 and KHCO3) were introduced into the preparation process simultaneously. The physicochemical properties of biochar were studied by means of SEM, BET, XRD, XPS and so on. The characterization results confirmed that the vascular bundle structure of bamboo can be well preserved by pyrolysis under ammonia atmosphere combined with green activation, and the nitrogen atoms were successfully introduced into the biochar’s skeleton uniformly. The physicochemical properties of biochar can be adjusted suitable for high phenol adsorption and supercapacitor electrodes at different temperatures. Optimum nitrogen-doped biochar showed a high phenol adsorption capacity of 169.5 mg/g at 25 ℃ and exhibited exceptional specific capacitance of 208 F/g at the current density of 1 A/g due to its unique nanoporous structures and surface functional groups. This novel nanoporous nitrogen-doped bamboo chips have great application potential in pollutant removal and energy storage.