Lignosulfonate-modified corncob cellulose biochar as an electrode material for high-performance supercapacitor...

Area of Science:

• Materials Science
• Electrochemistry
• Renewable Energy

Background:

• Cellulose biochar is a promising electrode material for energy storage due to its properties.
• Lignocellulosic materials require pretreatment for optimal biochar production.
• Developing efficient and sustainable methods for biochar synthesis is crucial.

Purpose of the Study:

• To develop a simplified method for producing high-quality cellulose biochar from corncob.
• To investigate the effect of bisulfite pretreatment and lignosulfonate on biochar properties.
• To evaluate the electrochemical performance of the synthesized biochar for energy storage.

Main Methods:

• Corncob was pretreated with bisulfite, followed by direct pyrolysis without washing.
• Potassium hydroxide (KOH) was used for activation at 900 °C.
• The resulting biochar (ABU-900) was characterized and tested in electrochemical devices.

Main Results:

• The unwashed pretreated corncob biochar (ABU-900) achieved a high specific surface area of 3130 m²/g.
• The biochar demonstrated excellent electrochemical stability with 94.1% coulombic efficiency after 5000 cycles.
• An asymmetric supercapacitor using ABU-900 exhibited a specific capacitance of 141.2 F/g and high energy density.

Conclusions:

• Bisulfite pretreatment and retained lignosulfonate enhance biochar properties and introduce sulfur heteroatoms.
• This method offers a facile and effective route for producing advanced cellulose biochar electrodes from waste biomass.
• The developed biochar shows significant potential for high-performance energy storage devices.