The ZnCl2 chemical activation method is widely employed for the preparation of biomass-derived porous carbons. In most of the related studies, the emphasis lies on investigating how experimental preparation conditions impact the performance of the final products. However, the performance of the porous carbon also depends on the chemical structure of the carbon source. In this study, we used alkali lignin, ammoxidized lignin and sodium lignosulfonate as carbon sources to prepare porous carbon through ZnCl2 activation. The influence of the chemical structures of lignin on the activation process is explored. The porous carbons prepared from alkali lignin (ALC) and ammoxidized lignin (AOLC) both exhibit similar and relatively high specific surface areas (ALC: 1164 m2 g− 1, AOLC: 1156 m2 g− 1) and capacitance contribution ratios (ALC: 80.6%, AOLC: 79.4%). The porous carbon prepared from sodium lignosulfonate has a specific surface area of 890 m2 g− 1 and a mesopore ratio of 26.1%, with the capacitance contribution accounting for only 75.1%. ZnS and NaCl generated during the activation process involving sodium lignosulfonate can partially enable mesopores by template effect, which in turn results in lower electrochemical properties. This study explores the reasons for the differences in ZnCl2 activation on different lignins, providing data to support research on the mechanism of how lignin structure influences ZnCl2 activation.

Effect of precursor structure on the pore structure and capacitance properties of porous carbons prepared by zinc chloride activation
    Abstract
    1 Introduction
    2 Experimental section
        2.1 Preparation of lignin-derived porous carbon
        2.2 Material characterization
        2.3 Preparation of porous carbon electrode
        2.4 Electrochemical measurements
    3 Results and discussion
    4 Conclusion
    Acknowledgements 
    References

• Guishan Liu(Guangdong Provincial Key Laboratory of Plant Resources Biorefinery, School of Chemical Engineering and Light Industry, Guangdong University of Technology (GDUT), 100 Waihuan Xi Road, Panyu District, Guangzhou 510006, China)
• Tao Huang(Guangdong Provincial Key Laboratory of Plant Resources Biorefinery, School of Chemical Engineering and Light Industry, Guangdong University of Technology (GDUT), 100 Waihuan Xi Road, Panyu District, Guangzhou 510006, China)
• Xihong Zu(Guangdong Provincial Key Laboratory of Plant Resources Biorefinery, School of Chemical Engineering and Light Industry, Guangdong University of Technology (GDUT), 100 Waihuan Xi Road, Panyu District, Guangzhou 510006, China)
• Wenli Zhang(Guangdong Provincial Key Laboratory of Plant Resources Biorefinery, School of Chemical Engineering and Light Industry, Guangdong University of Technology (GDUT), 100 Waihuan Xi Road, Panyu District, Guangzhou 510006, China, School of Advanced Manufacturing, Guangdong University of Technology (GDUT), Jieyang 522000, China, Jieyang Branch of Chemistry and Chemical Engineering Guangdong Laboratory (Rongjiang Laboratory), Jieyang 515200, China) Corresponding author
• Yingjuan Sun(School of Advanced Manufacturing, Guangdong University of Technology (GDUT), Jieyang 522000, China, Jieyang Branch of Chemistry and Chemical Engineering Guangdong Laboratory (Rongjiang Laboratory), Jieyang 515200, China) Corresponding author
• Hai Li(School of Advanced Manufacturing, Guangdong University of Technology (GDUT), Jieyang 522000, China)