预制铂纳米颗粒对质子交换膜燃料电池用铂纳米线阴极的结构影响

铂纳米线（Pt NWs）由于其独特的结构特点，比商业Pt/C具有更高的氧还原反应（ORR）比活性。在本工作中，我们将预先制备好的铂纳米颗粒（Pt NPs）引入到碳基体中，用于诱导生长Pt NWs，获得了均匀分布Pt NWs的阴极。通过改变Pt NP载量（0~0.015 mg·cm^-2）和Pt NP来源（不同Pt含量的Pt/C）研究了所制备阴极的结构和性能。用扫描电镜对阴极表面进行了表征，并用透射电镜和X射线衍射分析了Pt NW的形貌和晶体结构。在单电池中分别进行了极化曲线和循环伏安曲线测试。当Pt NP来源为40% Pt/C且其载量为0.005 mg·cm^-2时，制备的Pt NW阴极具有最佳的单电池性能和最大的电化学表面积（ECSA）。最后，提出了预制Pt NP影响Pt NWs分布的可能机制。

Effects of Preformed Pt Nanoparticles on Structure of Platinum Nanowire Cathode for Proton Exchange Membrane Fuel Cells

Pt nanowires (Pt NWs) have been demonstrated to have a higher specific activity of oxygen reduction reaction (ORR) than that of commercial Pt/C due to their unique structural characteristics. In this work, a cathode with a uniform distribution of Pt NWs was obtained by introducing preformed Pt nanoparticles (NPs) into the carbon matrix to induce Pt NW growth. The structure and performance of the as-prepared cathode were investigated by altering Pt NP loadings (0-0.015 mg·cm^-2) and Pt NP sources (Pt/C with different Pt contents). The cathode surface was characterized by scanning electron microscopy (SEM), and the morphology and crystal structure of Pt NW were analyzed by transmission electron microscopy (TEM) and X-ray diffraction (XRD). Polarization and cyclic voltammetry curves were obtained in single cells. The best single-cell performance, as well as the largest electrochemical surface area (ECSA) value was achieved by the cathode with preformed Pt NP loading of 0.005 mg·cm^-2 originating from 40% Pt/C. Finally, a possible mechanism for the influence of preformed Pt NPs in the Pt NW distribution was proposed.