NGHIÊN CỨU ỨNG DỤNG VẬT LIỆU THAN HOẠT TÍNH TỪ VỎ TRẤU LÀM ĐIỆN CỰC TRONG SIÊU TỤ ĐIỆN.

Abstract

Activated carbon (AC) has been synthesized from rice husk by chemical activation method using KOH, NaOH, mixture of (NaOH + Na2CO3) and mixture of (KOH + K2CO3) as the chemical activating agents. The activated carbon with specific surface area of about 2000 m2/g and high porosity which allows the absorption of a large number of ions has been applied as electrodes in supercapacitors or electric double layer capacitors (EDLCs).

The electrodes are fabricated by blending rice husk activated carbons with super-P and polyvinylidene difluoride (PVDF) under the weight ratio of 83:10:7. The AC electrodes and Nickel foams are immerged into Potassium hydroxide (KOH) solution as the electrolyte. The specific capacitance strongly depends on the pore structure of coal; thus, the highest specific capacitance has been 179 F/g corresponding to AC with the largest specific surface area. Additionally, different activation durations and chemical activating agents has been used to compare and determine the optimal parameters for synthesis of activated carbon with high surface area.