Electrocatalytic Activity of Electrodeposited Ni-P Micro-patterned Structure in Acidic Solution

電鍍鎳磷合金微構形結構之電催化活性研究

許臣翔(Chen-Hsiang Hsu) ； 李弘彬(Hung-Bin Lee) ； 林招松(Chao-Sung Lin) ； 李春穎(Chun-Ying Lee)

《中國機械工程學刊》 32卷2期 (2011/04) Pp. 103-109

https://doi.org/10.29979/JCSME.201104.0002

摘要

鎳磷合金為具有優異電解水產氫潛力之電極材料，本研究主要在探討利用微機電製程製備微構型表面對電極電催化活性之強化效果。微構型電極表面主要由直徑65微米、間距105微米及兩種不同高度之圓柱所構成。從電極在0.5M硫酸水溶液中所量測的動態極化曲線，在－0.75V（相對飽和甘汞電極）的電流密度從平面電極之181 mA cm^(-2)增加至微構型電極之426 mA cm^(-2)，增加了2.35倍的電催化活性。此一催化活性之增加明顯大於總電極表面積之增加量，應歸因於柱狀結構邊角處之電場集中現象。電場分析的結果也驗證出藉由增加圓柱高度以增加電極表面積之作法將有其限制，當柱間間格之深寬比大於1時，電力線就近乎無法到達電極底面，因此，在設計電極表面構型時就必須考量此一影響。

並列摘要

Ni-P alloy has been shown to be a potential electrode material for hydrogen production from electrolysis. The enhancement of its electrocatalytic efficiency with micro-patterned structures fabricated using MEMS process was investigated in this study. The cylindrical columns with diameter of 65μm and spacing of 105μm were fabricated in rectangular array and two different heights. From the potentiodynamic polarization curves measured in 0.5M H2SO4 solution, the current density at -0.75V vs saturated calomel electrode (SCE) was increased from 181mA cm^(-2) to 426 mA cm^(-2), planar electrode to micro-structured electrode, which denoted a 2.35 times increase for HER efficiency. It was noted that enhancement in HER efficiency was higher than the corresponding increment in apparent surface area. The electric field concentration at the edges of the columnar structure could contribute to the raise in efficiency. The computer simulation on the electric field distribution revealed that the effectiveness by raising the height of the microcolumns to increase the surface area had limitation. When the aspect ratio of the spacing channel between the columns became greater than 1, the electric flux was nearly unable to reach the bottom surface. Therefore, suitable configuration design in the micro-pattern is desired.

並列關鍵字

hydrogen evolution reaction ； Ni-P alloy ； micro-patterned electrode