Chitosan has been considered attractive in polymer electrolyte membrane fuel cells (PEMFCs) due to its excellent film forming and fuel barrier properties. Reflecting the limitation of its low proton conductivity, various materials were used to improve the proton conductivity of chitosan, through combination with inorganic materials like graphene oxide. We present an ideal molecular model for bio-nanocomposites and their mechanism of proton conductivity in PEMFCs. In this study, the diffusion behavior of hydronium ions in chitosan/graphene complex systems at various temperatures, concentrations and pH values were studied systematically using 3 ns long molecular dynamics (MD) simulations with an aim to provide the mechanisms of proton conductivity of chitosan/graphene composite at an atomistic scale. Various amounts of water content (10%, 20%, 30% and 40%), pH values (achieved by adjusting the protonation degree of amino groups of chitosan by 20%, 40%, 60%, 80% and 100%) and numbers of graphene sheets (1, 2, and 3) were considered during MD simulations at 4 temperatures (298 K, 320 K, 340 K and 360 K). Our results indicated that the chitosan system containing 40% water was the most suitable polymer electrolyte membrane and temperature was a key factor affecting diffusion proton. Adding graphene to the chitosan system and adjusting the pH values of chitosan were demonstrated to have a significant effect on improving the proton conductivity of the membrane.

壳聚糖因其出色的成膜性和燃料阻隔性而被认为在聚合物电解质膜燃料电池（PEMFC）中具有吸引力。反映其低质子电导率的局限性，通过与无机材料（如氧化石墨烯）结合使用各种材料来提高壳聚糖的质子电导率。我们为生物纳米复合材料及其质子电导率在PEMFCs中的理想分子模型。在这项研究中，使用3 ns长分子动力学（MD）模拟系统研究了在各种温度，浓度和pH值下壳聚糖/石墨烯络合物体系中水合氢离子的扩散行为，旨在提供壳聚糖/质子/质子电导率的机制。原子尺度的石墨烯复合材料。各种含水量（10％，20％，30％和40％），pH值（通过将壳聚糖的氨基的质子化度调整20％，40％，60％，80％和100％获得）和石墨烯片的数量（1、2和3）在4种温度（298 K，320 K，340 K和360 K）的MD模拟过程中考虑了这些因素。我们的结果表明，含水量为40％的壳聚糖体系是最合适的聚合物电解质膜，温度是影响扩散质子的关键因素。已证明向壳聚糖体系中添加石墨烯并调节壳聚糖的pH值对改善膜的质子传导性具有显著作用。320 K，340 K和360 K）。我们的结果表明，含水量为40％的壳聚糖体系是最合适的聚合物电解质膜，温度是影响扩散质子的关键因素。已证明向壳聚糖体系中添加石墨烯并调节壳聚糖的pH值对改善膜的质子传导性具有显著作用。320 K，340 K和360 K）。我们的结果表明，含水量为40％的壳聚糖体系是最合适的聚合物电解质膜，温度是影响扩散质子的关键因素。已证明向壳聚糖体系中添加石墨烯并调节壳聚糖的pH值对改善膜的质子传导性具有显著作用。