【摘要】 模拟了质子在质子交换膜(PEMs)中的输送过程。根据Nafion等磺化类PEMs的可能结构,借助无规行走模型研究了PEMs中不同组分间质子跃迁距离等参数对质子输送扩散系数的影响。并把从两维体系得到的结果和三维体系的结果进行比较,通过改变不同组分间的跃迁距离分析PEMs体系的变化,结果表明两者模拟结果无大的差别。已有文献表明质子在PEMs中输送是链段运动输送和质子跃迁输送双重作用的结果,二者的贡献大小取决于具体质子导电体系的种类。利用格子重排和无规行走模型研究了这两种机理对质子导电性能的贡献。更多还原

【Abstract】 Random walk simulation on proton transport in proton exchange membranes (PEMs) was studied in the present work. The model was used for the possible structure of sulfonated membranes. Effects of the jump distance between different compositions on diffusion coefficient were discussed by means of random walk model. It was indicated that there is no significant difference between the simulation results from two dimensional system and three dimensional system. Proton transport in PEMs was contributed by both segmental motion and hoping of protons in most cases, which were stated in some experimental reports. The content of two kinds of contributions to proton transport depends on the specified system of proton conductivity. The extents of these two contributions were studied by the model of lattic rearranging and random walk in this work. The diffusion coefficient was denoted in this paper by quantity and half-quantity analysis.更多还原