Scanlon L G, Balbuena P B, Zhang Y, Sandi G, Back C K, Feld W A, Mack J, Rottmayer M A, Riepenhoff J L
Air Force Research Laboratory, Electrochemistry & Thermal Sciences Branch, Wright-Patterson AFB, OH 45433, USA.
J Phys Chem B. 2006 Apr 20;110(15):7688-94. doi: 10.1021/jp0574403.
Molecular simulations for hydrogen physisorption with corannulene molecules arranged according to their crystal structure result in good agreement with the weight-percent hydrogen stored as determined experimentally employing a 3-g sample of highly crystalline corannulene at ambient temperatures and 72 bar of pressure. Calculated enthalpies of adsorption for corannulene/hydrogen molecular systems obtained from ab initio calculations which take into account electron correlation via second-order Möller-Plesset perturbation theory are in good agreement with literature experimental enthalpies of adsorption for activated carbons interacting with molecular hydrogen. Ab initio results also show that corannulene molecules arranged in a sandwich structure are important for approximately doubling the binding energy of corannulene interacting with molecular hydrogen through a cooperative interaction. To test the effects of finite temperatures and pressures, stack arrays were used as input for molecular dynamics simulations and indicate that physisorption mechanisms including van der Waals forces and dipole-induced dipole interactions may yield enhanced adsorption capacity in relation to other carbon-based materials. These results will be instrumental in identifying interlayer separations of an array of corannulene or related molecules that may provide a high weight percent of physisorbed hydrogen.
对按照其晶体结构排列的碗烯分子进行氢物理吸附的分子模拟结果，与在环境温度和72巴压力下使用3克高结晶度碗烯样品通过实验测定的储存氢的重量百分比高度吻合。通过考虑二阶Möller-Plesset微扰理论中的电子相关性的从头算得到的碗烯/氢分子体系的计算吸附焓，与文献中关于活性炭与分子氢相互作用的实验吸附焓高度一致。从头算结果还表明，以夹心结构排列的碗烯分子对于通过协同相互作用使碗烯与分子氢相互作用的结合能增加约一倍很重要。为了测试有限温度和压力的影响，堆叠阵列被用作分子动力学模拟的输入，并表明包括范德华力和偶极-诱导偶极相互作用在内的物理吸附机制相对于其他碳基材料可能产生更高的吸附容量。这些结果将有助于确定一系列碗烯或相关分子的层间间距，这些间距可能提供高重量百分比的物理吸附氢。
