Research Of Alkaline Carbohydrate Fuel Cell Based On The Silicon-based Nano Composite Electrode

The research and application of fuel cell in the communication base stations and portable electronic devices has been carried out for many years, and the commercialization has been started gradually. Comparing with hydrogen and methanol fuel cell, carbohydrate is one of the more promising fuel with safe, nontoxic and huge equivalent weight. Silicon-based nano-materials have large surface area, high mechanical stability and maintain compatibility with microelectronics process. After forming the composite with functional materials which have catalytic activity, the catalytic activity can be excited because of synergistic effects. This type of structure has been used to many kinds of fuel cell devices. In order to fabricate an alkaline carbohydrate fuel cell based on Pd-Ni/SiNWs composite electrodes, the mainly works are listed as following:First, the orderly SiNWs arrays with lager surface have been fabricated by Metal-Assisted Chemical Etching. Then, the structure of Pd-Ni/SiNWs has been fabricated by electroless deposition and galvanostatic deposition. Scanning electron microscopy, X-ray diffraction and energy dispersive spectroscopy are used to evaluate the structure and composition of this electrode. The relative standard deviation of fifty scanning by cyclic voltammograms is 4.33%, which shows the Pd-Ni/SiNWs electrode has good electrochemical stability. The electrochemically active surface area of Pd-Ni/SiNWs is one hundred times larger than Pd-Ni/Si, it is about 51.5 cm2.Next, the electrocatalyst oxidation ability of Pd-Ni/SiNWs to carbohydrates is investigated. Taking KOH as electrolyte, cyclic voltammetry, chronoamperometry, tafel curve and open circuit potential-time are used to research the electrocatalyst oxidation ability in higher and lower concentration. Glucose, fructose, maltose, lactose, sucrose and starch are selected as test subjects. The results show that the Pd-Ni/SiNWs composite electrodes have high catalytic oxidation ability and stability for four types of reducing sugar. In addition, the current response presents linear feature in lower concentration.Finally, the experimental data have been integrated, contrasted and analyzed, and the simple carbohydrates fuel cell has been constructed. Taking glucose as an example, the open circuit potential is 0.89 V and the short circuit current is about 10 mA. Besides, combining the results and relevant literatures, the catalytic oxidation mechanism is discussed.In conclusion, the research methods and results can provide certain reference values for broadening the fuel sources of fuel cell, enriching the theory of alkaline direct fuel cell and exploring the new source of energy.