Pd–Ni Alloy Nanoparticle/Carbon Nanofiber Composites: Preparation, Structure, and Superior Electrocatalytic Properties for Sugar Analysis

• Published in: Analytical chemistry (Washington) Vol. 86; no. 12; pp. 5898 - 5905
• Main Authors: Guo, Qiaohui, Liu, Dong, Zhang, Xueping, Li, Libo, Hou, Haoqing, Niwa, Osamu, You, Tianyan
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 17-06-2014
• Subjects: Carbohydrates - analysis; Carbon - chemistry; Catalysis; Electrocatalysis; Electrodes; Metal Nanoparticles; Microscopy, Electron, Scanning; Microscopy, Electron, Transmission; Nanofibers; Nanoparticles; Nickel - chemistry; Nickel alloys; Palladium - chemistry; Photoelectron Spectroscopy; Scanning electron microscopy; Sugar; Thermogravimetric analysis; Thermogravimetry; X-Ray Diffraction
• ISSN: 0003-2700; 1520-6882
• DOI: 10.1021/ac500811j

Novel Pd–Ni alloy nanoparticle/carbon nanofiber (Pd–Ni/CNF) composites were successfully prepared by a simple method involving electrospinning of precursor polyacrylonitrile/Pd­(acac)2/Ni­(acac)2 nanofibers, followed by a thermal process to reduce metals and carbonize polyacrylonitrile. The nanostructures of the resulting Pd–Ni/CNF nanocomposites were carefully examined by a combination of scanning electron microscopy (SEM), transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), high-angle annular dark field (HAADF)-scanning transmission electron microscopy (STEM), energy dispersive X-ray (EDX), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and X-ray photoelectron spectra (XPS). For all the nanocomposites, the Pd–Ni alloy nanoparticles (NPs) were dispersed uniformly and embedded firmly within the framework or on the surface of CNF. The size, composition, and alloy homogeneity of the Pd–Ni alloy NPs could be readily tailored by controlling the feed ratio of metal precursors and the thermal treatment process. Cyclic voltammetric studies showed enhanced redox properties for Pd–Ni/CNF-based electrodes relative to the Ni-metal electrode and significantly improved electrocatalytic activity for sugar (e.g., glucose, fructose, sucrose, and maltose) oxidation. The application potential of Pd–Ni/CNF-based electrodes in flow systems for sugars detection was explored. A very low limit of detection for sugars (e.g., 7–20 nM), high resistance to surface fouling, excellent signal stability and reproducibility, and a very wide detection linear range (e.g., 0.03–800 μM) were revealed for this new type of Pd–Ni/CNF nanocomposite as the detecting electrode. Such detection performances of Pd–Ni/CNF-based electrodes are superior to those of state-of-the-art nonenzymatic sugar detectors that are commercially available or known in the literature.