Lu Zhenjiang, Qin Wenjin, Ma Juan, Cao Yali, Bao Shujuan
State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources, College of Chemistry, Xinjiang University, Urumqi 830046, China.
Department of Science and Technology, Xinjiang University, Urumqi 830046, China.
Molecules. 2023 Jul 9;28(14):5296. doi: 10.3390/molecules28145296.
Direct formic acid fuel cells (DFAFCs) are one of the most promising power sources due to its high conversion efficiency; relatively low carbon emissions, toxicity, and flammability; convenience; and low-cost storage and transportation. However, the key challenge to large-scale commercial applications is its poor power performance and the catalyst's high preparation cost. In this study, a new sandwich-structured Pd/polypyrrole-graphene/Pd (Pd/PPy-Gns/Pd)-modified glassy carbon electrode (GCE) was prepared using a simple constant potential (CP) electrodeposition technique. On the basis of the unique synthetic procedure and structural advantages, the Pd/PPy-Gns/Pd shows a fast charge/mass transport rate, high electrocatalytic activity, and great stability for formic acid electro-oxidation (FAO). The mass activity of Pd/PPy-Gns/Pd electrode reaches 917 mA·mg. The excellent catalytic activity is mainly due to the uniform embedding of Pd nanoparticles on the polypyrrole-graphene (PPy-Gns) support, which exposes more active sites, and prevents the shedding and inactivation of Pd nanoparticles. At the same time, the introduction of graphene (Gns) in the PPy further improved the conductivity of the catalyst and accelerated the transfer of electrons.
直接甲酸燃料电池（DFAFCs）因其高转换效率、相对较低的碳排放、毒性和可燃性、便利性以及低成本的储存和运输，成为最具前景的电源之一。然而，大规模商业应用面临的关键挑战是其较差的功率性能以及催化剂的高制备成本。在本研究中，采用简单的恒电位（CP）电沉积技术制备了一种新型三明治结构的Pd/聚吡咯 - 石墨烯/Pd（Pd/PPy - Gns/Pd）修饰玻碳电极（GCE）。基于独特的合成工艺和结构优势，Pd/PPy - Gns/Pd对甲酸电氧化（FAO）表现出快速的电荷/质量传输速率、高电催化活性和良好的稳定性。Pd/PPy - Gns/Pd电极的质量活性达到917 mA·mg。优异的催化活性主要归因于Pd纳米颗粒均匀地嵌入在聚吡咯 - 石墨烯（PPy - Gns）载体上，这暴露出更多的活性位点，并防止了Pd纳米颗粒的脱落和失活。同时，在PPy中引入石墨烯（Gns）进一步提高了催化剂的导电性并加速了电子转移。
