在本研究中，我們利用電化學沉積法合成具奈米結構的鎳鐵磷合金，並將其應用在中性環境下產氫反應。此電觸媒的物化特性是透過掃描式電子顯微鏡、拉曼光譜儀、感應耦合電漿原子發射光譜儀、X光光電子能譜儀、線性掃描伏安法、循環伏安法和計時電位法來進行分析。結果發現電鍍電流密度和電鍍液的組成對所製備的鎳鐵磷合金電觸媒的表面型態以及化學組成具有極大的影響。例如，在高電流密度(geq -2 mA cm-2)、低Ni/Fe莫爾數(le 2)比和不含磷的濃度(0 M)之條件下，可製備出具奈米立方體結構之鎳鐵磷合金，而在低電流密度、低鐵濃度和含有不同磷濃度之條件下，則可製備出具奈米球形結構之鎳鐵磷合金。此外，在最佳的合成條件下所製備之鎳鐵磷合金電觸媒表現出優良的產氫活性，在中性環境下分別需要260.5±0.01 和200 mV之過電位去達到10 mA cm-2的電流密度以及37.29±5.81的轉換頻率。

In this study, nanostructured nickel-iron-phosphorus alloys (nanoNiFePx) were synthesized by electrochemical deposition and their applications as the electrocatalysts for the hydrogen evolution reaction (HER) were investigated. The physicochemical properties of the prepared nanoNiFePx were characterized using scanning electron microscopy, Raman spectroscopy, inductively coupled plasma mass spectrometry, and X-ray photoelectron spectroscopy, linear sweep voltammetry, cyclic voltammetry, and chronopotentiometry. It was found that deposition current density and composition of plating solution used for the electrosynthesis of nanoNiFePx had great influences on the surface morphology and chemical composition of the prepared nanoNiFePx. For example, electrodeposition with high deposition current density (geq -2 mA cm-2), low Ni/Fe molar ratio (le 1), or phosphorus-free content (0 M) resulted in the formation of NiFePx nanocubes, whereas electrodeposition with low deposition current density, low iron content, or any amount of phosphorus favored the formation of NiFePx nanospheres. In addition, nanoNiFePx prepared with optimal synthetic conditions exhibited the best HER activity, requiring overpotentials of 260.5±0.01 and 200 mV to achieve a current density of 10 mA cm-2 and turnover frequency of 37.29±5.81 h-1 at neutral pH, respectively.

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