摘要: | 本研究在開發電化學快速積層製造,以本研究室所開發之微陽極導引電鍍技術(micro-anode guided electrochemical deposition, MAGE)為基礎,來製備鎳鉬、鎳磷、鎳鋅及鎳鐵等三維鎳基合金微柱,使其具有奈米晶與非晶結構,擁有高比表面積、低析氫電位之特性。應用上,由此等微柱製成電極陣列,將可做為電解水產氫之陰極(鎳鉬、鎳磷、鎳鋅)和陽極(鎳鐵),具有長效性與高性能。在學術上,本計畫著眼於局部微電鍍鎳基合金微柱的機制探討,有別於傳統平板電鍍,屬於非對稱性電場之高電流電鍍之理論範疇,文獻上罕見探討。對於銅、鎳等純金屬局部微電鍍之機制,本團隊雖已有詳細討論,但對較複雜合金鍍浴之機制則尚待理解,因此執行本計畫,具有研究創新性。研究內容主要在理解析鍍參數(如: 析鍍間距、偏壓、合金離子濃度、酸鹼值)對析鍍產物之合金組成分佈、結晶結構,以及材料特性與析氫效率之影響。研究目標,則以局部微電鍍技術在合金鍍液中,製作直徑在100 ~ 1000 μm範圍,高度可達15 mm之自我支撑型高強度鎳合金微柱。所得合金在形成電極陣列,將可取代傳統平板電鍍鎳基合金,突破二維多孔膜產氫之限制,作為高性能、長壽命之電解水產氫陰極與陽極材料,以增進電解水之析氫反應(hydrogen evolution reaction, HER)和釋氧反應(oxygen evolution reaction, OER)效能,另一方面,也將有助於鎳基合金常溫積層製造技術(additive manufacturing technology, AMT)的發展。 ;In this project, we focus on developing a rapid process of the electrochemical additive manufacturing method. This process is based on the micro-anode guided electrochemical deposition (MAGE) technique that is well established in our laboratory to prepare the alloying nickel-based 3-D pillars, such as Ni-Mo, Ni-P, Ni-Zn, and Ni-Fe. Due to the microstructure of nanocrystals and amorphous, these alloying pillars characterize with a very high specific surface area and low hydrogen evolution potential. In application, the array established by these pillars provides a useful cathode (Ni-Zn, Ni-Mo, and Ni-P) and anode (Ni-Fe) in the water electrolysis. They are durable and high efficient electrodes in the performance of water electrolysis. Theoretically, MAGE is exerted with high current density in an asymmetrical electrical field. The mechanism is quite different from that of the conventional planar electroplating process, conducted at low current density in the symmetrical electrical-field. This alloying mechanism is seldom reported in the literature, even though we have discussed the mechanism for the pure metal very well. In this work, the effect of the experimental parameters on the alloying composition, microstructure, and characterization of the Ni-alloying pillars is of interest. The goal of this work is to prepare the self-supported Ni-alloying pillars with a diameter ranging in 100 ~ 1000 μm in height up to 15 mm. The cathode array made of Ni-based (Ni-Zn, Ni-Mo, and Ni-P) pillars and the anode array made of Ni-Fe was investigated to perform the water electrolysis. We expected that these arrays of 3-D Ni-alloying pillars are much more efficient on the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) as compared to those constructed by the conventional 2-D thin-films, porous films, and dendritic structures. This project is also contributed to the development of additive manufacturing technology (AMT) on nickel-based alloys at room temperature. |