Heteroatom-doped lignin-derived carbon material: performance and application

Industrial waste lignin can be used as a sustainable resource to prepare carbon materials, which has been considered an important strategy for the substitution of coal-based carbon. However, a review summarizing the design mechanism of heteroatom-doped lignin-derived carbon materials and their application performance is lacking. Herein, we reviewed the recent progress on heteroatom-doped lignin-based carbon applied in energy storage applications such as batteries and capacitors, environmental fields such as removing contaminants from the air and water, substance testing for iron/chromium ions, and catalysis. More importantly, we present a critical discussion with respect to the effect of heteroatom-doping (e.g., N-doping and N/S/O/P co-doping) on the physicochemical properties including the BET area, defect structure, hydrophilicity/hydrophobicity, electric conductivity, and electron density of lignin-based carbon materials. Particularly, the effects of the above-mentioned properties on the reversible capacity, rate performance, and cycling performance of batteries; the capacitance and energy density of capacitors; and the adsorption capacity of lignin-based carbonaceous adsorbents for the removal of pollutants are concluded. Finally, we propose the future perspective and challenges in applying lignin-based carbon materials in energy storage and environmental fields. This review summarizes the influence of heteroatom-doping on the physicochemical properties of lignin-based carbon, together with its electro-chemical property in batteries and capacitors and adsorption ability for the removal of pollutants.