Lee Jaeyong, Mishra Avnish Kumar, Choi Chungryong, Kim Dokyoung, Kim Eun Young, Yong Kijung, Kim Jin Kon
National Creative Research Initiative Center for Smart Block Copolymers, Pohang University of Science and Technology, Pohang, Kyungbuk 790-784, Republic of Korea.
Surface Chemistry Laboratory of Electronic Materials, Department of Chemical Engineering, Pohang University of Science and Technology, Pohang, Kyungbuk 790-784, Republic of Korea.
ACS Appl Mater Interfaces. 2020 Apr 1;12(13):15667-15674. doi: 10.1021/acsami.9b23009. Epub 2020 Mar 18.
We fabricated 3D nanoporous metal structures from poly(2-vinylpyridine)--poly(4-vinylpyridine) copolymer (P24VP) thin film with vertically oriented lamellar nanodomains by coordinating corresponding metal precursors followed by reduction to metals. Although metal precursors are coordinated with both P2VP and P4VP blocks, the metal coordination power toward P4VP block is much greater than that toward P2VP block. Thus, most of the metal precursors are located in the P4VP block, while a few exist in the P2VP block. After the metal precursors were reduced to corresponding metals by reactive ion etching, metals located in P4VP regions became continuous main frames. However, metals in P2VP regions could not be continuous because of smaller amounts, resulting in nanoporous structures. Using these 3D nanoporous structures, we measured the electrocatalytic activity for hydrogen evolution reaction. 3D nanoporous platinum (Pt) showed enhanced catalytic activity compared with Pt flat film due to the large surface area. Moreover, 3D nanoporous Pt/cobalt bimetallic structures showed better catalytic activity than 3D nanoporous Pt structures.
我们通过使相应的金属前体配位，随后还原为金属，从具有垂直取向层状纳米域的聚（2-乙烯基吡啶）-聚（4-乙烯基吡啶）共聚物（P24VP）薄膜制备了三维纳米多孔金属结构。尽管金属前体与P2VP和P4VP嵌段都配位，但金属对P4VP嵌段的配位能力远大于对P2VP嵌段的配位能力。因此，大多数金属前体位于P4VP嵌段中，而少数存在于P2VP嵌段中。通过反应离子蚀刻将金属前体还原为相应的金属后，位于P4VP区域的金属成为连续的主框架。然而，由于数量较少，P2VP区域中的金属无法连续，从而形成纳米多孔结构。使用这些三维纳米多孔结构，我们测量了析氢反应的电催化活性。由于表面积大，三维纳米多孔铂（Pt）与Pt平板薄膜相比显示出增强的催化活性。此外，三维纳米多孔Pt/钴双金属结构比三维纳米多孔Pt结构显示出更好的催化活性。
