本研究中所使用的金屬硫化物陶金靶材是由本實驗室熱壓機自行壓製而成，利用RF磁控濺鍍法在低沉積溫度下能夠成功地製備出具高電催化特性之Ag/MoSx薄膜。實驗中，探討靶材中不同Ag含量比例，不同硫化物與氧化物添加對於薄膜品質及電化學特性之影響。我們也利用EDS、SEM、RAMAN、XRD、TEM、雙頻道恆電位/電流/交流阻抗儀及XPS來分析薄膜特性。
實驗係使用自製的陶金靶材，以濺鍍功率70瓦、固定沉積溫度及固定氬氣流量，製備不同Ag含量之n-Ag/MoSx (n= 0、1、2、3與4)薄膜。實驗結果顯示，薄膜表面呈現直立薄片狀結構。XRD量測得知，n-Ag/MoSx (n= 0、1、2、3與4)薄膜主要繞射峰屬於Hexagonal結構的2H-MoS2其(100)平面之繞射所貢獻。拉曼量測結果得知，不論添加銀與否，其特徵峰皆為MoSx之特徵峰，由TEM結果得知，發現添加之銀皆成極小奈米銀，量多且大小均勻，因此非高解析之檢測難以發現其存在。
由電化學性質量測結果得知，3-Ag/MoSx薄膜具有最佳之電化學特性，LSV量測中有著相當低的42 mV/dec Tafel斜率值，EIS阻抗量測僅2.59 ohm之低阻抗，CV量測中有最高雙層電容值58.1μF/cm2，在CstV穩定度量測中也有相當良好的高電流穩定度。

In this research, Ag/MoSx thin film electrodes with different Ag contents were used for electrocatalytic hydrogen evolution reaction (HER). The thin films were deposited on carbon fiber paper (CFP) by radio-frequency (RF) sputtering technique, while the Ag/MoS2 target was prepared using home-made hot press machine in our laboratory. In this experiment, besides the variation of Ag contents, different sulfides and oxides were also added in the target to observe their effects to electrochemical properties of the thin films. All the thin film properties were characterized and analyzed with XRD, SEM, TEM, RAMAN, XPS measurements, and electrochemical testing.
n-Ag/MoSx (n= 0, 1, 2, 3, and 4) thin films were deposited on CFP and Si(100) substrates at 300 oC with RF output power at 70 watt. The deposition of the thin films on Si (100) was carried out for characterization purposes only without testing for the electrochemical properties. The Ag/MoSx thin films exhibited a columnar-growth morphological feature that was possibly excellent for electrocatalytic HER due to the exposure of the active edge sites. XRD pattern showed that the growth preferential orientation of n-Ag/MoSx (n= 0, 1, 2, 3, and 4) thin films was (100) plane of MoS2 structure. Raman measurement also showed all the thin films exhibited the characteristic peak of MoS2, regardless of the silver contents.
According to the electrochemical measurements, the 3-Ag/MoSx thin film electrode exhibited the best properties for HER, as compared to other thin films with different Ag contents. The LSV measurement showed a relatively low Tafel slope of 42 mV/dec and EIS impedance measurement indicated low electron transfer resistivity of 2.59 ohm. Furthermore, CV measurement also revealed the thin film electrode had the highest double layer capacity (Cdl) of 58.1μF/cm2, which implied higher actively electrochemical surface area. Finally, the tests with different overpotentials also showed high stability of the thin film at high current density, which possibly can be applied for long-term industrial application.

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