Preparation and catalytic activity of thin-film cobalt–tungsten–boron for the hydrolysis of ammonia borane
Preparation and catalytic activity of thin-film cobalt–tungsten–boron for the hydrolysis of ammonia borane
复制标题
DOI：
10.1016/j.ijhydene.2022.06.084
复制
发表时间：
2022-06
影响因子：
7.2
通讯作者：
Yan Wang;Xue Wang;Jian Ren;Fengyan Xu;Kecheng Zhang;Z. Cao;Shiwei Wu;Guode Li
中科院分区：
文献类型：
--
作者：
Yan Wang;Xue Wang;Jian Ren;Fengyan Xu;Kecheng Zhang;Z. Cao;Shiwei Wu;Guode Li
本文采用化学镀法在泡沫镍表面制备了纳米钴钨硼（Co-W-B）薄膜催化剂，并将其应用于氨硼烷（NH3BH 3）水解制氢反应中。采用XRD（粉末X射线衍射）、SEM（扫描电子显微镜）和EDS（能量色散X射线光谱）对Co-W-B纳米粒子的物理化学性质进行了表征。结果表明，Co-W-B在泡沫镍基体表面呈不规则球形结构。在制备过程中，沉积pH值的增加导致了粒径的变化。当pH值为11.5时，合成的Co-W-B粒径较小，表明沉积pH值直接影响催化剂颗粒的成核和生长。优化后的Co-W-B催化剂对NH3BH3水解反应具有较高的催化活性，室温下的比产氢速率为12933.3 mL min − 1·g − 1。此外，获得了较低的表观活化能47.3 kJ mol − 1。与以前报道的催化剂相比，所得催化剂的催化性能处于较好的水平。此外，在温和的NH3BH3水解条件下，重复使用性进行了研究。结果表明，所制备的Co-W-B薄膜在5次循环后仍保持优异的耐久性。提出了Co-W-B催化剂水解NH_3BH_3释放氢的可能机理。
In this work, cobalt–tungsten–boron nanoparticles (Co–W–B) have been successfully deposited on foam Ni to manufacture thin-film catalysts by electroless plating technique and applied in hydrogen generation from ammonia borane (NH3BH3) hydrolysis. Physicochemical properties of Co–W–B nanoparticles are characterized by XRD (Powder X–ray diffraction), SEM (Scanning electron microscopy), and EDS (Energy dispersive X–ray spectroscopy). It is observed that Co–W–B showed irregular spherical structure on the surface of foam Ni substrate. An increase of depositional pH value in the preparation process leads to the change of particle size. When the pH value is equal to 11.5, as-synthesized Co–W–B exhibits the smaller particle size, which suggests that depositional pH value has directly impacted the nucleation and growth of catalysis particles. The optimized Co–W–B catalyst displays higher catalytic activity toward NH3BH3hydrolysis with a specific rate of hydrogen generation of 12933.3 mL min−1·g−1at room temperature. Moreover, the lower apparent activation energy of 47.3 kJ mol−1is achieved. Compared with previously reported catalysts, the as-obtained catalytic performance is situated at the better rank. Moreover, the reusability has been investigated under the mild NH3BH3hydrolysis conditions. It reveals that as-fabricated thin-film Co–W–B maintains excellent durability after five cycles. A possible mechanism for the released hydrogen from NH3BH3hydrolysis using Co–W–B catalyst has been proposed.