在紙基底材料上透過雷射誘導產生電極之研究

Study of Laser-Induced Electrode on Paper-Based Materials

林宏洋(Hong-Yang Lin)

指導教授 ： 江宏仁

國立臺灣大學/工學院/應用力學研究所/碩士(2020年)

https://doi.org/10.6342/NTU202000490

摘要

在本論文中利用雷射誘導石墨烯（laser-induced graphene）之技術來做為紙基底感測器上之電極，由於紙基底材料可變形之特性，其石墨烯的表面結構受到紙基底之影響產生了不同的變化。本論文即探討雷射誘導之石墨烯在紙的不同側受到彎曲變形時，其作為電極使用之特性變化，發現電極位於凹面與凸面有兩種截然不同的電阻變化模式，當電極於凹面受到彎曲，其隨著彎曲程度變大，電阻值將會越低，而當電極於凸面受到彎曲，其電阻將比未彎曲前來的大，我們透過了材料間的重疊與裂縫來解釋此現象。而除了探討其內部物理模型外，由於其為紙基底材料，壽命較不穩定，故我們透過塗布高分子的方式來保護其結構，使其訊號穩定並讓使用壽命大幅延長，其亦使得電阻變化模式產生了改變。
由於上述研究之成功，我們試圖在透明的玻璃紙上也重現以上之結果，卻發現其有另一種複雜之物理機制。透過非對焦雷射，我們可使一些物質固定於玻璃紙上，例如加入一些導電墨水，可使玻璃紙也成為可設計電極形狀之材料，且由於玻璃紙會吸水的特性，我們發現其電阻值會隨著濕度產生變化，故我們亦探討其電阻與濕度變化間之關係。而除了固定導電墨水以外，利用相同方式我們也成功發展出其他應用，例如：將磁性物質固定於玻璃紙表面使其可以被磁鐵所吸引，以及將澱粉固定於玻璃紙表面，使其成為能檢測含碘液體之感測紙…等等。
最後將另外提出紙基底感測器於人工智慧手勢辨識上之應用，透過將添加高分子後的感測器安裝於手套上，量測不同手勢其訊號之變化，結合機器學習與深度學習來個別訓練感測器，使其具有能辨識手勢數字0到9之能力，有望開拓紙質感測器於各式領域之應用。

關鍵字

雷射誘導石墨烯 ； 紙基底感測器 ； 高分子 ； 玻璃紙 ； 人工智慧 ； 手勢辨識

並列摘要

In this study, laser-induced graphene(LIG) technology is used as an electrode on a paper-based sensor. Due to the deformable property of the paper-based material, the surface structure of graphene affected by the paper is different. We study the change of property of the graphene as an electrode when LIG is subjected to bending deformation on different sides of the paper. We found that the electrode located on the concave side and the convex side has two distinct resistance change modes. When the electrode is curved on the concave side, the resistance value will be lower as the curvature of paper becomes larger. When the electrode is curved on the convex side, the resistance value will be larger than unbent state. We explain this phenomenon through overlaps and cracks in material. Because it is paper-based material, its performance is not stable. In addition to discussing the internal physical model, we also protect the structure of electrode by coating polymer to make signal stable and extend the lifecycle significantly, which also affect the resistance change mode.
Based on the above study, we tried to reproduce the result of the cardboard on transparent cellophane, and we found that it has another complicated physical mechanism. By defocus laser, we can lock some materials on cellophane. For example, after absorbing some conductive inks, cellophane can also become a material that can be designed in the shape of electrode. Moreover, because cellophane could absorb water, we found that the resistance value changes with humidity, so that we study the relationship between resistance and humidity changes. Besides locking conductive inks, we have also successfully developed other applications in the same way, such as locking magnetic substances on the surface of cellophane so that it can be attracted by magnets, and locking starch on the surface of cellophane so that it could be a sensor which can detect iodine-containing liquid, and so on.
Finally, we apply paper-based sensors to artificial intelligence gesture recognition.
After installing the sensor which is coated polymer on the glove, we measure the signal change of different gestures, and train the sensors with machine learning and deep learning individually, so that it can recognize the gesture of number 0 to 9. It is expected to expand the application of paper-based sensor in various fields.

並列關鍵字

laser-induced graphene ； paper-based sensor ； polymer ； cellophane ； artificial intelligence ； gesture recognition

參考文獻

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