本研究將木屑作為活性碳前驅物，選用硝酸鉀作為活化劑，利用熱分解會產生大量氣體之特性，進行碳化與活化，製備出高比表面積及孔隙率的活性碳。活性碳製備流程包含木屑前處理、碳化與活化以及後處理，並改變活化劑的比例、鍛燒升溫速率和鍛燒溫度來探討各個實驗參數對活性碳的影響，其中加入克里金模型優化實驗過程，減少實驗組數，精確預測數據結果，有效率地製備出高比表面積的活性碳。
活性碳樣品將利用SEM、TEM、XRD、元素分析、氮氣等溫吸脫附曲線、拉曼光譜法和XPS等方法，分析不同的活化劑比例和鍛燒溫度對於活性碳物理化學性質的影響。克里金模型預測結果顯示，活化劑比例1.6g/g、鍛燒升溫速率20°C/min和鍛燒溫度900°C時，活性碳比表面積能夠高達2326.59m^2/g，而實際實驗比表面積為2548.41m^2/g，誤差值約為8.7%，代表克里金模型在本研究中具高度準確性及可靠性。
本研究選用最高比表面積及孔體積的活性碳製備成電雙層超級電容，並透過循環伏安法、電化學交流阻抗頻譜和恆電流充放電進行電性分析。結果顯示，具有高比電容(157.8 F/g)和能量密度(39.94 Wh/kg)，且在經過5000次的充放電循環壽命測試後，仍擁有約80%的電容保留率。

This study utilized wood sawdust as the precursor material for activated carbon, with potassium nitrate (KNO₃) employed as the activating agent. By leveraging the characteristic of potassium nitrate to release substantial amounts of gas during thermal decomposition, the processes of carbonization and activation were executed to synthesize activated carbon with superior specific surface area and porosity. The preparation procedure encompassed sawdust pretreatment, carbonization and activation, as well as post-treatment steps. Experimental parameters, including the activating agent ratio, calcination heating rate, and calcination temperature, were systematically varied to examine their impacts on the properties of the resulting activated carbon. Additionally, a Kriging model was applied to optimize the experimental process, reduce the number of experimental trials, and accurately predict outcomes, successfully producing activated carbon with a high specific surface area.
Characterization of the activated carbon samples was performed using SEM, TEM, XRD, elemental analysis, nitrogen adsorption-desorption isotherms, Raman spectroscopy, and XPS to investigate the influence of activating agent ratio and calcination temperature on their physicochemical properties. The Kriging model predicted that an activating agent ratio of 1.6 g/g, a calcination heating rate of 20°C/min, and a calcination temperature of 900°C would yield an activated carbon with a specific surface area of 2326.59 m²/g. The experimentally measured specific surface area was 2548.41 m²/g, resulting in a prediction error of approximately 8.7%, thereby demonstrating the high accuracy and reliability of the Kriging model in this study.
The activated carbon with the highest specific surface area and pore volume was subsequently fabricated into an electric double-layer supercapacitor. Electrochemical analyses, including cyclic voltammetry, electrochemical impedance spectroscopy, and constant current charge-discharge tests, revealed excellent performance, with a specific capacitance of 157.8 F/g and an energy density of 39.94 Wh/kg. Furthermore, after 5000 charge-discharge cycles, the supercapacitor retained approximately 80% of its initial capacitance, underscoring its outstanding cyclic stability.

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