從自然環境中的水體運動擷取能量是非常必要的，不僅可以緩解對能源的能源需求，也可以讓電子設備自我供電。石墨烯是一種具有多功能性的二維材料，可應用於收集能量。為了改善影響石墨烯誘發電壓產生的因素，我們製作了一種新型實驗裝置，可以透過擷取環境中的水體運動來產生電能。
本論文主要探討石墨烯暴露於溶液的不同面積比例(w/L)時對產生電壓的影響。利用光阻來定義溶液流經石墨烯的面積比例(w/L)，使用PDMS作為流道及電極的防水層。首先，我們發現了誘導電壓會隨著溶液濃度提高而提高。其次，比較氯化氫(HCl)、氯化鈉(NaCl)和氯化鉀(KCl)三者不同溶液對誘導電壓的影響。由於半徑較小的陽離子與石墨烯表面π-電子具有較強的庫倫力能緊密吸附在石墨烯表面，因此氫離子(H^+)的誘導電壓會比鈉離子(Na^+)和鉀離子(K^+)大。最後，探討石墨烯晶片以不同比例的面積(w/L)暴露在溶液中產生的誘導電壓。值得注意的是誘導電壓的最大值是接觸比例40%(w/L=0.4/1)與60%(w/L=0.6/1)，而在接觸比例50%(w/L=0.5/1)的誘導電壓卻低於接觸比例40%(w/L=0.4/1)和60%(w/L=0.6/1)，形成M型的對稱結構。另外我們也發現誘導電壓對於溶液的流動情形非常敏感。
綜合本論文的實驗結果可以得到以下結論：電荷載子的數量不僅隨接觸比例(w/L)而變化，而且也隨著溶液濃度而變化，其次才取決於與石墨烯接觸的液體的類型。最重要的是多數載子的類型可透過改變接觸比例(w/L)來調節。我們展示了石墨烯晶片能量轉換的可行性也提供調整石墨烯的多數載子的方法，讓石墨烯晶片在不同的場合中的應用變更靈活，例如：透過海浪、河流或是雨水來獲取藍色能源。

Harvesting energy from ambient water motions is highly necessary, which is not only to reduce demand on energy but also to realize the self-powered electronic devices. Graphene is a functional material which we can utilize it to harvest the energy. To improve the factors of the induced voltage generation by the graphene, we prepared a new experimental device which can generate electricity through harvesting ambient water motions. In this study, we mainly discusses various contact ratio (w/L) of graphene exposed to the solution influencing on the induced voltage. Photoresist is used to define the contact ratio (w/L) of the solution flowing through the graphene. It was found that the contact ratio of 40% (w/L=0.4/1) and 60% (w/L=0.6/1) generate the maximum value of the induced voltage. However, the induced voltage of the contact ratio 50% (w/L=0.5/1) is lower than the contact ratio of 40% (w/L=0.4/1) and 60% (w/L=0.6/1). The diagram for the induced voltage with different contact ratios look like an M-type symmetrical structure. The type of majority carrier can be adjusted by changing the contact ratio (w/L) between the graphene and the electrolyte solution. This work provides the feasibility of energy conversion using graphene chips and a method for adjusting the majority carriers to the graphene, allowing the feasibility of the graphene to be more flexible for harvesting blue energies from nature.

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