本實驗主要探討石墨烯暴露於溶液之面積比例不同時電壓的變化。我們利用正光阻S1813來定義溶液會流經石墨烯的面積比例，以銅片作為電極，以PDMS作為流道，並利用3D印表機來印製我們所需要的載台及容器。一開始我們以緩慢的流速進行實驗，發現儀器偵測不到訊號，透過法拉第箱的測試，我們推測是訊號過小以致於儀器偵測不到，所以我們利用水槽儲存溶液，再透過重力使溶液的流速提高，才順利偵測到訊號。我們發現隨著溶液濃度提高，石墨烯產生的電壓也會提高，但濃度提高到一定值後，電壓就不會再明顯的提升。而電壓也會隨著流速的提升而增加。以不同種類的溶液進行實驗發現氯化鋰溶液產生的電壓略比氯化鉀溶液產生的電壓高。石墨烯以不同比例面積暴露在溶液的實驗中發現50%的比例產生的電壓最小，40%與60%的比例產生的電壓最大。

In this thesis, we investigated the induced voltage of liquid solution flowing over a graphene surface. The induced voltage changes with respect to different contact ratio of the liquid over the graphene surface. The contact ratio is defined as the ratio of the area of the graphene contacted by liquid solution to the total surface area of the graphene. The area of the graphene not to be contacted by liquid is covered by the photoresist S1813. We utilize copper pieces as the electrodes. We use Polydimethylsiloxane (PDMS) to fabricate the channel. The working platform and liquid tank are made by a 3D printer. It was observed that the flow speed over the graphene surface has to exceed a critical value in order to detect the induced electric voltage by a source meter.
The induced voltage is enhanced by raising the concentration or the flow velocity of the liquid solution. But the induced voltage shows no significant increase when a critical concentration or flow velocity is achieved. The voltage induced by lithium chloride (LiCl) solution is higher than potassium chloride (KCl) solution. Local minimum voltage is obtained under 50% contact-ratio condition. Local maximum voltage is obtained under 40% and 60% contact-ratio condition, respectively, which is consistent with our former theoretical study.

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