本研究以友善環境、低成本的綠色製程合成出具有高比表面積及高孔體積之多重孔洞碳材，並探討不同孔洞性質、結晶度、石墨化程度等材料表徵應用於電雙層電容的性能表現。實驗上以林業廢棄物銀合歡為例，先經由初步絕氧碳化，再經過高溫熱裂解活化，即可獲得多重孔洞碳材，其比表面積經由 2D-NLDFT model 計算後可高達 1000 m2/g 以上，孔體積也能達到 0.8 cm3/g 以上。並嘗試以其他三種生物炭作為炭源進行比較，結果發現其孔徑分布皆在活化後有明顯提升，證明本研究之活化法適合用於各類型之生物炭。
依照反應機構的不同可以分為化學活化及物理活化。化學活化主要透過 KOH、K2CO3 等作為主要活化劑，在水溶液中與 CaCO3 硬模板均勻混合，在高溫環境下使鉀離子與碳發生反應，進而在生物炭表面侵蝕出孔洞，最後以鹽酸洗去無機模板。所產生的鈣離子廢液能夠滴加鹼源，透過沉積活化法使其鈣離子沉澱在孔洞內部形成 CaCO3，加入活化劑後即可再次進行活化，以達到廢液回收、綠色製程的目標。物理活化法則是透過 CO2 作為主要活化劑，本研究選擇以漁業廢棄物文蛤殼作為 CO2 來源，因其具有 99% 以上之CaCO3¬ 含量，能夠在高溫環境下分解產生 CO2，並接續與碳材發生 Boudouard reaction，進而在碳材表面侵蝕出孔洞。由於此種活化方式使用到的碳源、活化劑皆屬於天然廢棄物，因此大大降低了成本考量，同時也能減少原物料之碳排放，達到友善環境、碳中和之概念。
將活化後之多重孔洞碳材應用於超級電容，在有機電解液 (TEABF4/PC) 系統中可以達到 120 F/g 以上的電容值 (掃速為 2mV/s)，並且在高掃速的情況下 (200 mV/s) 仍然可以維持 70% 以上的電容保留率。此外，在經過 10000 次的循環壽命測試後，放電電容量皆能夠保持在 80 % 以上，證明在多次循環之後，仍具有良好的穩定性。最後，本研究之電雙層電容能夠達到約 20 Wh/kg 的能量密度，同時表現出約12000 W/kg 之高功率密度。
整體而言，本研究提供不同活化方式將多種生物炭合多重孔洞碳材，不僅成本低廉，同時符合綠色製程，在電容方面也有良好的表現性。

Mutiporous carbon is widely recognized as one of the most commonly utilized materials for supercapacitor electrodes due to its exceptional characteristics, including high specific surface area, high porosity, and excellent conductivity. These characteristics greatly facilitate the adsorption of a substantial quantity of charge within the pores, resulting in an enhanced energy density. In this study, we propose a sustainable chemical approach for synthesizing multiporous carbon with high specific surface areas, utilizing forestry wastes. White Popinac Wood (WPW) were selected as the carbon source, which were then undergo preliminary anaerobic carbonization and high temperature thermal cracking to expand the pore by chemical activation (KOH) or physical activation (CO2). The multiporous carbon with high specific surface area (~1100 m2/g) and high pore volume (~0.8 cm3/g) was obtained. The application of multiporous carbon in supercapacitors demonstrates a notable specific capacitance (higher than 120 F/g, 2 mV/s) in an organic electrolyte (TEABF4/PC) system. Even when subjected to a high scan rate of 200 mV/s, the capacitance retention of the multiporous carbon remains above 70%. After subjecting the multi-porous carbon to 10,000 cycles of lifetime testing, the discharge capacitance remains above 80%, indicating excellent stability even after numerous cycles. Finally, The electric double-layer capacitors (EDLCs) investigated in this study achieve an impressive energy density of approximately 20 Wh/kg while exhibiting a high power density of around 12,000 Wk/g. In conclusion, this study provides various activation methods for synthesizing multi-porous carbon from diverse biochar sources. These methods not only effectively reduce costs but also minimize carbon emissions, aligning with the principles of environmental friendliness and carbon neutrality.

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