A neural-network-like catalyst structure for the oxygen reduction reaction: carbon nanotube bridged hollow PtCo alloy nanoparticles in a MOF-like matrix for energy technologies
A neural-network-like catalyst structure for the oxygen reduction reaction: carbon nanotube bridged hollow PtCo alloy nanoparticles in a MOF-like matrix for energy technologies
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用于氧还原反应的类神经网络催化剂结构：用于能源技术的类 MOF 基质中的碳纳米管桥接空心 PtCo 合金纳米颗粒
DOI：
10.1039/c9ta06712d
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发表时间：
2019
影响因子：
11.9
通讯作者：
Wei Zidong
中科院分区：
文献类型：
--
作者：
Wang Jian;Wu Guangping;Wang Wanglan;Xuan Wenhui;Jiang Jingxia;Wang Jianchuan;Li Li;Lin Wen Feng;Ding Wei;Wei Zidong
膜电极组件中催化层的合理设计是质子交换膜燃料电池（pemfc）实现高性能的关键。在此，受大脑神经网络结构的启发，我们构建了一个用于氧还原反应（ORR）的仿生催化网络，通过建立pt -有机配体- co2 + -有机配体- pt连接，然后将其热转化为金属-有机框架（MOF）样基质，其中平均粒径为4.4 nm的中空PtCo合金纳米颗粒（NPs）通过碳纳米管桥接在一起（PtCo@CNTs-MOF）。仿生催化网络提供了各种物种运输通道与活性位点的高效连接；因此，与传统的Pt/C催化层相比，传质效率提高了一个数量级。此外，由Pt NPs衍生的空心PtCo合金显示出852 mA mgPt−1 @ 0.90 V的高初始质量活度，并且在加速老化试验中未检测到衰减。因此，最终实现了燃料电池阴极的Pt利用率为58 mgPt kW - 1，阳极和阴极的Pt利用率分别为98 mgPt kW - 1。后者几乎是传统催化层的3倍。此外，基于仿生催化网络的燃料电池在1 A cm−2的温度下连续工作130小时，没有检测到衰变。该策略为设计超低铂负载、高活性和耐用的催化层提供了新概念，可用于燃料电池及其他领域。
The rational design of a catalytic layer in a membrane-electrode assembly is the key to achieve high performances from proton exchange membrane fuel cells (PEMFCs). Herein, inspired by the neural-network structure of the brain, we constructed a bionic catalytic network for the oxygen reduction reaction (ORR), via setting up Pt-organic ligands–Co2+–organic ligands–Pt connections and then thermally transforming them into a metal-organic-framework (MOF)-like matrix in which hollow PtCo alloy nanoparticles (NPs) with an average particle size of 4.4 nm are bridged together by carbon nanotubes (PtCo@CNTs-MOF). The bionic catalytic network provides highly efficient linkages of various species-transport channels to active sites; as a result, an order of magnitude improvement is achieved in mass transfer efficiency as compared to the traditional Pt/C catalytic layer. Besides, the hollow PtCo alloy derived from Pt NPs shows a high initial mass activity of 852 mA mgPt−1 @ 0.90 V and an undetectable decay in an accelerated aging test. Accordingly, a remarkable Pt utilization efficiency of 58 mgPt kW−1 in the fuel cell cathode and 98 mgPt kW−1 in both the anode and cathode was eventually achieved, respectively. The latter is almost 3 times higher than that of the traditional catalytic layer. Moreover, no decay was detected during continuous operation at 1 A cm−2 for 130 hours from the bionic catalytic network based fuel cell. This strategy offers a new concept for designing an ultra-low Pt loading yet highly active and durable catalytic layer for fuel cell applications and beyond.