鈀鎳複合膜之製備、特性分析及其氫/氮選透性之研究

隨著半導體、化工及光電工業的發展，對於氫氣純度的要求亦愈高，氫氣純度不夠，將導致物件毒化而使效能降低，氫氣純化的重要性日愈彰顯。本研究係以無電鍍共析鍍法製備鈀鎳合金/多孔氧化鋁複合膜，經由改變鍍液中氨水含量、氯化鎳克數、鍍液pH值及析鍍時間，製作不同Ni含量之Pd-Ni合金複合膜，探討析鍍參數對Pd-Ni合金膜之組成結構及氫氣純化性能的影響。實驗結果顯示；氨水含量由120 ml/L增至180 ml/L，Pd-Ni合金膜中鎳含量由51 at.％降至23 at.％；氯化鎳25 g/L增至27 g/L，鎳含量由7 at.％增至53 at.％；pH值由10提升至11，鎳含量由16 at.％增至63 at.％；析鍍時間由10分鐘增至60分鐘，鎳含量由45at.％增至63 at.％，隨著Pd-Ni合金膜中鎳含量的增加，組成相由Pd逐漸變成PdNi相，Pd-Ni合金膜的表面形貌為連續膜上散佈著微細晶粒，微細晶粒隨鎳含量增加會有增大粗化的現象。利用Pd，Pd90Ni10及Pd80Ni20金屬膜進行氫氣滲透實驗，探討鎳含量對鈀鎳合金膜之氫氣選透性影響。純鈀膜的氫氣透過係數為2.2~3.6×10-7 mole/ m2sec-Pa，鈀鎳合金膜的氫氣透過係數3.73~8.81×10-7 mole/ m2-sec-Pa。純鈀膜的氮氣透過係數0.721~1×10-7 mole/m2-sec-Pa，鈀鎳合金膜的氮氣透過係數1.1~2.8×10-7 mole/m2-sec-Pa。純鈀的氮氣/氮氣選透係數介於2.54∼4.11，Pd90Ni10的氮氣/氮氣選透係數在2.66∼4.26之間，Pd80Ni20的氮氣/氮氣選透係數在2.85∼4.22之間，添加10 at.％Ni和20 at.％Ni與純鈀的性質相近，表示鈀鎳合金膜取代純鈀膜是可行的。

關鍵字

氫氣純化；無電鍍製程； Pd ； PdNi ；多孔氧化鋁

並列摘要

The demand of hydrogen has increased for the development of semiconductor, chemical and photoelectric industries. The purification of hydrogen is important since the impurity in hydrogen may cause the degradation of produce. 　In this study, the PdNi alloy film was co-deposited on porous alumina to form the PdNi/Al2O3 composite membrane used the electroless plating. The PdNi alloy films contained various Ni contents were manufactured by change the contents of ammonia and nickel chloride in plating solution, the pH value of plating solution and the deposition time. The effects of Ni content on the microstructure and the hydrogen purification of PdNi alloy films were investigated. The Ni content of PdNi alloy film is decreased from 51 to 23 at.％ as the content of ammonia in plating solution increased from 120 to 180 ml / L. The Ni content of PdNi alloy film is increased from 7 to 23 at.％, 16 to 63 at.％ and 45 to 63 at.％ as the content of nickel chloride in plating solution increased from 25 to 27 g / L, the pH value of plating solution increased from 10 to 11 and the deposition time increased from 10 to 60 min, respectively. The Pd phase was transformed to PdNi phase in PdNi alloy film and the tiny grains on surface were grown to large particles when the Ni content in PdNi alloy film increased. The hydrogen permeability and nitrogen permeability of Pd film are 2.2~3.6×10-7 and 0.721~1×10-7 mole/m2-sec-Pa. The hydrogen permeability and nitrogen permeability of PdNi alloy film are 3.73×10-7~8.81×10-7 and 1.1~2.8×10-7 mole/m2-sec-Pa. The separation factor（H2/N2）of Pd film is about 2.54∼4.11. The separation factors（H2/N2）of Pd90Ni10 and Pd80Ni20 are about 2.66∼4.26 and 2.85∼4.22. The hydrogen permeability of PdNi alloy is similar to that of pure Pd indicated that the PdNi alloy replaces the Pd as hydrogen separation membrane is feasible.