本論文分為三個部分，在第一部分將具羧酸官能化且擴孔的中孔洞二氧化矽SBA-16，簡稱為LP-S16C-x，x = [CES/(CES+TEOS)]。將LP-S16C-x含浸於鈷銅金屬離子前驅液，利用熱還原法將金屬離子還原成金屬奈米顆粒(CoyCu10-y-LP-S16C-x-TD)。含浸的過程中，在鹼性環境下 (pH = 9) ，中孔洞表面上的羧酸官能基團(-COOH)去質子化形成負離子(-COO-)，因此有靜電作用力，能夠有效地吸引金屬離子進入孔洞中，成功還原鈷銅奈米金屬顆粒在此中孔洞材料，其金屬顆粒尺寸為5 - 7 nm之間。將材料應用於4-Nitrophenol還原催化反應之觸媒，Co2Cu8-LP-S16C-20表現最佳的催化效果，其活性參數為1519.5 s-1gmetal-1。 在第二部分中，將LP-S16C-20含浸於鈷銅離子前驅液，利用化學還原法將金屬離子還原成金屬奈米顆粒 (CoyCu10-y-LP-S16C-20)，其金屬顆粒大小為2 - 4 nm之間。將材料使用於硼烷氨水解製氫的反應中，比起單金屬材料，具有鈷銅金屬的材料表現了較佳的催化活性，當鈷銅比例為4：6 (Co4Cu6-LP-S16C-20)，表現最好的催化效果，其在反應中的轉換率為16.36 H2 mol/metal mol•min、活化能為38.10 kJ/mol。 第三部分將LP-S16C-20含浸於鈷鎳離子前驅液，利用化學還原法還原金屬 (CoyNi10-y-LP-S16C-20)，金屬的顆粒大小約為2 – 7 nm，將具有金屬之中孔洞材料進行硼烷氨水解製氫反應，發現具有鈷鎳金屬的材料表現較佳的催化活性，Co6Ni4-LP-S16C-20的轉換率為18.95 H2 mol/metal mol•min、活化能為36.43 kJ/mol。結果顯示含奈米金屬之中孔洞材料有效提升硼烷氨水解反應的反應速率。 ;In first project, we report that the bimetallic cobalt-copper alloy nanoparticles with a particle size about 5.3 nm are successfully supported in the cage-type mesopores of large pore SBA-16 mesoporous silica (sample denoted as CoyCu10-y-LP-S16C-x-TD) functionalized with carboxylic acids (–COOH) groups. During the impregnation of metal solutions ,the –COOH groups on the surface of cage-type mesopore deprotonate under the alkaline condition (pH=9) and become negatively charged, with efficiently interact with Co2+/Cu2+ cations and allow facile fabrication of Co-Cu alloy nanoparticles. The CoyCu10-y-LP-S16C-x-TD catalyst exhibits a high catalytic activity with the activity parameter of 1519.5 (s-1gmetal-1) when it was used as the catalyst for the reduction of 4-nitrophenol.
In second project, non-noble bimetallic CoyCu10-y nanoparticles were successfully supported on the LP-S16C-20 (CoyCu10-y-LP-S16C-20-DD) by using chemical reduction with aqueous solution of NaBH4 and NH3BH3. While the cost-effective CoyCu10-y (2 - 4nm) was used for the hydrolysis of ammonia borane, the Co4Cu6-LP-S16C-20-DD showed high catalytic properties with turnover frequency of 16.36 H2 mol/metal mol•min and activation energy of 38.10 kJ/mol. The synergistic effect between Co and Cu species plays an important role for the improved performance in the catalytic hydrolysis of ammonia borane.
In third project, we report on the synthesis of CoyNi10-y nanoparticles supported on LP-S16C-20 and their catalytic activities for the hydrolytic dehydrogenation of ammonia borane. The catalysts of CoyNi10-y-LP-S16C-x-DD have been prepared by chemical reduction with aqueous solution of NaBH4 and NH3BH3. Compared with their monometallic counterparts, the bimetallic CoNi alloy NPs (2-7 nm) present higher catalytic activity for hydrolytic dehydrogenation of ammonia borane. The Co6Ni4-LP-S16C-20-DD nanocatalyst showed high catalytic properties with turnover frequency of 18.95 H2 mol/metal mol•min and activation energy of 36.43 kJ/mol. Alloying Co with Ni provides a required synergistic effect on the catalysis in the catalytic hydrolytic dehydrogenation of ammonia borane.
