Analysis of Cyclic Voltammetry dan Galvanostatic Charge Discharge Electrode Supercapacitor based on activated carbon from Kepok Banana Leaf (Musa balbisiana)

Abstrak. Teknologi penyimpan energi elektrokimia yang ramah lingkungan merupakan aspek yang penting dalam menunjang kinerja sistem konversi energi terbarukan. Studi ini menyiapkan elektroda superkapasitor berbahan asal karbon aktif berpori limbah daun pisang kepok. Sampel dipreparasi melalui impregnasi Natrium hidroksida pada konsentrasi 0,5 m/L dan dipirolisis satu tahap meliputi karbonisasi dan aktivasi fisika. Serbuk karbon yang dihasilkan dikonversi dalam bentuk pellet atau monolit dengan menggunakan hidraulik press tanpa adanya penambahan bahan perekat. Proses karbonisasi dilakukan dari suhu kamar hingga 600 °C pada lingkungan gas N2 sedangkan proses aktivasi fisika dilakukan dari suhu 600 °C hingga pada suhu tinggi dengan tiga jenis suhu yang berbeda meliputi 700 °C, 800 °C, dan 900 °C pada lingkungan gas CO2. Analisis densitas ditinjau sebagai evaluasi awal elektroda karbon berpori. Lebih lanjut, sifat elektrokimia superkapasitor dievaluasi melalui dua teknik yang berbeda meliputi teknik cyclic voltammetry (CV) dan galanostatic charge discharge (GCD) pada sistem dua elektroda dalam elektrolit 1 M H2SO4. Kapasitansi spesifik pada teknik CV adalah sebesar 142 F/g sedangkan dengan teknik GCD menghasilkan kapsitansi spesifik sebesar 154 F/g pada resistansi 42∙10-3Ω. Rapat daya dan rapat energi yang dihasilkan berturut-turut 20,45 Wh/kg dan 38,32 W/kg. Hasil ini mengkonfirmasi bahwa daun pisang berpotensi dijadikan sebagai karbon aktif berpori untuk material dasar elektroda superkapasitor.Abstract. Environmentally friendly electrochemical energy storage technology is an important aspect of supporting global energy fulfillment as a contribution to improving the performance of renewable energy conversion systems. Currently, supercapacitors are considered as a superior electrochemical energy storage technology compared to others. This study performed a supercapacitor with electrodes made from porous activated carbon based on biomass waste, especially banana leaf waste. The sample was prepared by sodium hydroxide impregnated at a concentration of 0.5 m/L dan one-step pyrolysis both carbonization dan physical activation. The carbon powder is converted into pellets or monoliths using a hydraulic press without the addition of any adhesive materials. The carbonization process is performed from room temperature to 600 °C in an N2 gas environment while the physical activation process is carried out from a temperature of 600 °C to a high temperature with three different types including 700 °C, 800 °C, dan 800 °C in CO2 gas atmosphere. Density analysis is reviewed as an initial evaluation of the porous carbon electrode. Furthermore, the electrochemical properties of the supercapacitor were evaluated through two different techniques including cyclic voltammetry (CV) dan galvanostatic charge-discharge (GCD) in a two-electrode system in 1 M H2SO4 electrolyte. The specific capacitance in the CV technique is 142 F/g while the GCD technique produces a specific capacitance of 154 F/g at resistance of 42∙10-3 Ω. The power density dan energy densities for the K-900 are 20.45 Wh/kg dan 38.32 W/kg, respectively. These results confirmed that banana leaves have the potential to be used as porous activated carbon for the supercapacitor electrode.

High Potential of Averrhoa bilimbi Leaf Waste as Porous Activated Carbon Source for Sustainable Electrode Material Supercapacitor

The energy cost-effective/free-environmental pollution concerns have an interest in bio-waste materials for the production of porous activated carbon, especially as electrode material for electrochemical energy storage devices such as li-ion batteries and supercapacitors. In this study, Averrhoa bilimbi leaf wastes were selected as a porous activated carbon source for sustainable electrode material supercapacitor. Porous activated carbons were prepared by chemical activation of 0.5 ml−1 sodium hydroxide solution at an optimum temperature of 800 °C pyrolyze in an environment of N2 and CO2 gases. The monolith coin shape of activated carbon is maintained by optimizing the self-adhesive properties of the precursor without the addition of adhesive materials. All coin monoliths feature a turbostratic to highly amorphous carbon structure. Furthermore, the relatively high monolith dimensional shrinkage of 42.00% initiated the development of a better pore framework carbon. In symmetric supercapacitors, electrochemical behavior confirmed a high specific capacitance of 149.04 F/g at a constant density of 1.0 A/g. Moreover, the maximum energy density was found of 10.50 Whkg−1 at an optimum power density of 116.35 W/kg in an aqueous electrolyte of 1 ml−1 Na2SO4. With bio-recycled waste, relatively easy preparation, and high electrochemical properties, porous activated carbon based on Averrhoa bilimbi leaf has great potential as a sustainable electrode material for supercapacitor energy storage applications.

Porous Activated Carbon Binder-free Scleria sumatrensis Stem-Based for Supercapacitor Application

Green, sustainable and effective development technique to obtain high porous activated carbon biomass based is important to boosting supercapacitor performance with environmentally friendly effect as conversion system and energy storage devices. We reported porous activated carbon binder-free Scleria sumatrensis stem-based as electrode material high performance of symmetric supercapacitor. Precursor biomass of Scleria sumatrensis stem was converted into porous carbon through simple ZnCl2 impregnated with different concentration of 0.4M, 0.5M, 0.6M, and 0.7M at high-temperature phyrolysis. All samples confirmed good amorphous carbon with small amounts of oxidative compounds. In two-electrode system, the optimum sample of ACSS0.6 significantly boosting the specific capacitance as high as 142.62 F g−1 at scan rate of 1 mV s−1. Furthermore, the optimum energy density was found to be 19.80 Wh kg−1 at a maximum power density of 71.35 W kg−1 in 1 M H2SO4 aqueous electrolyte. These results confirm that the porous activated carbon binder-free Scleria sumatrensis stem-based through simple ZnCl2 impregnated as an electrode material to boosting the electrochemical behavior of supercapacitors.