氫氣在釋放能量的過程中，沒有二氧化碳等溫室氣體的產出，相當具有發展潛力，而電解水產氫(water electrolysis)是目前產生氫氣常用的方法，擁有高效能、產生氫氣純度高、使用便利等特色。
本文利用白金電極並以玻璃U型管為電解槽，強鹼性KOH為電解質溶液，固定輸入電量進行電解水實驗的參數探討，各種工作參數如電解質濃度、電流密度、溫度對所需電壓之影響，找出較佳電解值濃度，以改善電解水產氫的效率。
實驗結果顯示提昇溫度對電解效率的影響很大，溫度由27℃至75℃，每提昇25℃電解效率就增加5~6%。實驗前預估白金電催化效果與電解液離子傳輸現象隨著溫度而有所不同，較佳濃度會隨著不同溫度而有所改變，實驗結果並未顯示出明顯的差異，較佳電解質濃度不隨著溫度而改變，較佳KOH濃度仍為30%。

During the process of releasing energy, hydrogen produce no green-house-effect gas and has a potential as a energy carrier in the future. Among the methods of hydrogen production, water electrolysis has many advantages, such as high efficiency, high purity in producing hydrogen, easy in use, etc., and thus become one of popular methods.
In this study, we use platinum electrodes and modified experimental set-up to study the effects of working parameters, such as concentration of electrolyte, current, voltage, and the time on the efficiency of electrolysis. Based on the data recorded by AUTOLAB power supply and the energy consumed through electrolysis, we can find out the optimum parameters for water electrolysis to improve the hydrogen production efficiency of water electrolysis.
The results of experiment show that temperature greatly affects the electrolysis efficiency. Each increase of 25℃ gives electrolysis efficiency raising about 5% to 6% from 27℃ to 75℃. Before experiment, I predict that electrocatalytic of Pt and ion transfer of electrolyte would differ from temperature. It’s also found that the relation between temperatures with better concentrations for better electrolysis efficiency is so week and in most conditions the better concentration of KOH is 30%.

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