“…The peaks centered at 44.5, 51.8, and 76.4° correspond to the (111), (200), and (220) planes of the Ni phase . Notably, no Pt characteristic peaks can be detected in both the Pt 0.04 /Ni-DA and Ni-DA-Pt composites because the excessively high-intensity peaks of the Ni nanoparticles may obscure the relatively weak peaks of Pt nanoparticles. , To get a better understanding of the existing form of Pt in Pt 0.04 /Ni-DA and Ni-DA-Pt, the majority of Ni nanoparticles were etched by hydrochloric acid after the first pyrolysis process and labeled as Pt 0.04 /Ni(H)-DA and Ni(H)-DA-Pt, respectively. After etching, the characteristic peaks of pure Pt and Ni are still absent in the Pt 0.04 /Ni(H)-DA composite, while a peak located at 43.4° between the characteristic peaks of pure Pt and Ni can be observed.…”