本研究製備胺基化氧化石墨烯(-NH2-GO)、-CD修飾氧化石墨烯(-CD-GO)以及未修飾的氧化石墨烯並以石英晶體微天平方法(quartz crystal microbalance; QCM)探討胺基化及非胺基化氧化石墨烯之低濕度感測特性。利用兩種不同長度碳鏈的胺基端化合物ethylenediamine 及1,6-hexanediamine上的NH2官能基與GO上的COOH進行醯胺化反應，以製備兩種不同長度碳鏈的胺基化氧化石墨烯，並與非胺基化修飾氧化石墨烯(-CD-GO)及GO進行比較，探討GO上所修飾的官能基的種類對於低濕感測的差異性。利用QCM的吸附動力學探討GO上所修飾的官能基的種類對於水分子的低濕感測特性。由實驗結果顯示GO有與水分子最大的結合常數值(associate constant value)，其原因是因GO外端的-COOH相較於-NH2、-CD等官能基會與水分子具有更大的氫鍵結合力，固其頻率變化量較大，因此具有較強的低濕度吸附特性。對開發新型低濕感測器而言，可利用QCM結合吸附動力學探討何種材料適合於製備低濕度感測器。
Low-humidity sensing properties of functionalized graphene oxide (GO) thin films that had –COOH, -CONHC2H4NH2, -CONH(C2H4)3NH2 and -cyclodextrin (-CD) functional groups were investigated by using a quartz crystal microbalance (QCM). The functionalized GO thin films were characterized by atomic force microscopy (AFM) and Fourier transform infrared spectroscopy (FTIR). Water vapor molecules were easily adsorbed onto the functionalized GO thin film that had –COOH functional group, but hardly adsorbed onto the functionalized GO thin film that had -CONH(C2H4)3NH2 functional group because of the difference hydrogen bond stability between water molecules and functionalized GO thin films. Adsorption dynamic analysis, molecular mechanics calculation (association constant), was applied to elucidate that the functional groups on the GO was related to the humidity-sensing properties (sensitivity), especially at low humidity levels.
