Department of Chemistry, Faculty of Science, Sri Chandrasekharendra Saraswathi Viswa Mahavidyalaya (SCSVMV University) , Enathur, Kanchipuram - 631 561, India.
ACS Appl Mater Interfaces. 2012 Jul 25;4(7):3620-6. doi: 10.1021/am300697q. Epub 2012 Jul 16.
A novel Pt nanoparticle (Pt NP) embedded aminoclay/Nafion (Pt/AC/N) nanocomposite catalyst film was prepared for oxygen reduction reaction by sol-gel method. The prepared nanocomposite films were surface characterized using XRD and TEM and thermal stability was studied by TGA. The prepared film has firmly bound Pt NP and could exhibit an improved electro-reduction activity compared to vulcan carbon/Nafion supported Pt NP (Pt/VC/N). Moreover, the Pt/AC/N film possessed good stability in the acidic environment. The limiting current density of the Pt/AC/N film with 35.4 μg/cm(2) of Pt loading was found to be 4.2 mA/cm(2), which is 30% higher than that of the Pt/VC/N. The maximum H2O2 intermediate formation was found to be ∼1.6% and the reaction found to follow a four electron transfer mechanism. Accelerated durability test for 2000 potential cycles showed that ca. 78% of initial limiting current was retained. The results are encouraging for possible use of the Pt/AC/N as the free-standing electrocatalyst layer for polymer electrolyte membrane fuel cells.
采用溶胶-凝胶法制备了一种新型的 Pt 纳米颗粒（Pt NP）嵌入的层状硅酸盐/全氟磺酸（Pt/AC/N）纳米复合催化剂膜，用于氧还原反应。使用 XRD 和 TEM 对所制备的纳米复合膜进行了表面特性表征，并通过 TGA 研究了其热稳定性。所制备的膜具有牢固结合的 Pt NP，与负载 Pt NP 的 Vulcan 碳/全氟磺酸（Pt/VC/N）相比，表现出更高的电还原活性。此外，Pt/AC/N 膜在酸性环境中具有良好的稳定性。Pt 负载量为 35.4μg/cm(2)的 Pt/AC/N 膜的极限电流密度为 4.2 mA/cm(2)，比 Pt/VC/N 高 30%。发现中间产物 H2O2 的最大形成量约为 1.6%，反应遵循四电子转移机制。经过 2000 个电位循环的加速耐久性测试，保留了初始极限电流的约 78%。这些结果对于将 Pt/AC/N 用作聚合物电解质膜燃料电池的独立电催化剂层具有重要意义。
