本研究透過簡單的一步水熱程序，成功在鎳泡綿上製備出在鹼性環境中HER與OER均表現出優異催化活性的雙功能催化電極。實驗中，我們調控不同反應物種如TAA、CTAB、Fe源、Mo源的濃度來沉積催化電極，透過SEM、EDS、XRD、Raman、XPS來分析表面特徵，並藉由雙頻恆電位/電流/交流阻抗儀量進行電化學測試。
根據實驗結果，添加的TAA會和鎳泡綿本身提供的Ni源產生反應，形成奈米樹狀結構之鎳硫化物Ni3S2，隨後添加之CTAB則作為陽離子表面活性劑使表面結構改變，形成奈米柱狀結構，不僅有調節結構和電子效益等特性，且會導致更高的比表面積，而有更多的催化活性位點和更好的導電性。Fe源的摻雜使柱狀結構之間多了額外了鐵硫化物FeS2奈米球狀結構，使OER性能大幅提升。最後添加的Mo源則會在水熱時形成厚的MoOx奈米顆粒結構覆蓋在Ni3S2、FeS2結構上。氧化鉬廣泛的變化性和可調性，使薄膜在HER電催化性方面有大幅度的提升。
電化學量測結果顯示，在1M KOH鹼性環境下，Mo0.5Fe0.25-1g CTAB/NS4薄膜有著良好的雙功能電催化性用於整體水分解。在LSV析氧反應量測中，為達到100 mA/cm2和500 mA/cm2 電流密度，過電位僅需0.23 V、0.34 V，Tafel斜率值為96 mV/dec。在析氫反應量測中，-10 mA/cm2、-100 mA/cm2電流密度下，過電壓分別僅需-0.17 V、-0.26 V， Tafel斜率值為 46 mV/dec。因有良好HER、OER性能，我們將Mo0.5Fe0.25-1g CTAB/NS4同時用作陰極和陽極，組裝成簡易鹼性電解槽，並用於量測整體水分解性能，在100 mA/cm2的電流密度下，可以得到1.71 V的電位，且在CstC量測中，也具有良好的穩定性。透過SEM、EDS、XRD、Raman、XPS等結構分析推斷薄膜表面有著Ni3S2、FeS2、MoOx等多相結構存在。

In this research, via a simple one-step hydrothermal procedure, we successfully prepared bifunctional electrocatalysts on nickel foam that had both HER and OER exhibit excellent performance in alkaline environment. During the experiment, we adjusted the concentrations of different materials, e.g. TAA, CTAB, Fe source, and Mo source. All the coating properties were characterized and anylyzed with SEM, EDS, XRD, Raman, XPS measurement, and electrochemical test.
According to the experimental results, the added TAA reacted with the Ni source from the nickel foam to form nickel sulfide Ni3S2 in the nano-dendritic structure. The added CTAB acted as a cationic surfactant to change the surface structure into nano columnar structure. The added CTAB not only have the characteristics of adjusting the structure and electronic benefits, but also makes film have higher specific surface area, so the formed deposit has more catalytically active sites and better conductivity. The addition of the Fe source formed iron sulfide FeS2 nanosphere structure between the columnar structures of Ni3S2 to provide the improved OER performance. Finally, the Mo source was added to form amorphous MoOx irregular bulk structures and to cover on the Ni3S2/FeS2 structure. Molybdenum oxide has a wide range of variability and tunability, which greatly improves the HER performance.
According to the electrochemical measurement results, Mo0.5Fe0.25-1g CTAB/NS4 film has excellent bifunctional catalytic performance for overall water splitting in 1M KOH. In the LSV oxygen evolution reaction (OER) measurement, to reach the catalytic current density of 100 mA/cm2 and 500 mA/cm2, it only required overpotentials of 0.23 V and 0.34 V, respectively, while the Tafel slope was 96 mV/dec. In the LSV hydrogen evolution reaction (HER) measurement, to reach the catalytic current density of -10 mA/cm2 and -100 mA/cm2 , it only required overpotentials of -0.17 V and -0.26 V, respectively, while the Tafel slope was 48 mV/dec . Due to its excellent HER and OER performance, Mo0.5Fe0.25-1g CTAB/NS4 was concurrently used as the cathode and anode, assembled into a simple alkaline electrolyzer, and used to measure the electrocatalytic performance of the overall water splitting. In the LSV measurement, we achieved potential of 1.71 V at a current density of 100 mA/cm2. In CstC measurement the film also had good stability for 20 hours. With the analyses of SEM, EDS, XRD, Raman, XPS, we has identiied that the catalytic electrode is a multi-phase structure of Ni3S2, FeS2, and MoOx.

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