【摘要】 用分子力学力场模拟法预测材料的储氢性能,为实验合成提供理论指导,降低开发成本和时间,有重要的实用意义。本文采用第一性原理推导的分子力学力场及巨正则系综蒙特卡洛模拟(GCMC)法和Feyman-Hibbs有效势计算氢分子在MOF-5体系的吸附曲线,所得不同温度和压力下的超额及绝对吸附曲线均与实验吻合良好,表明模拟法和力场的准确性。于是,预测了一系列不同MOFs材料的储放氢性能后,探讨材料结构和储氢能力。发现化学结构相似的MOFs材料,影响材料储放氢能力的关键因素是材料的自由体积。更多还原

【Abstract】 Computational prediction of hydrogen storage capabilities of various materials could provide guidance to experimental work and reduce the development cost.In this paper,we report an ab initio force field developed for hydrogen and MOFs materials.The force field was used to predict hydrogen adsorption isotherm curves using GCMG method.The Feynman-Hibbs effective potential was used for correction of the quantum effect.The predictions on MOF-5 agree well with the experimental data,which validated the force field and simulation protocol.The predicted isotherm curves of different MOFs indicate that void fraction is the key factor affecting hydrogen storage in materials with similar chemical structures.更多还原