单壁碳纳米管储氢过程的GULP模拟

利用GULP软件的蒙特卡罗模块对常温(T=300 K)下单壁碳纳米管(SWNT)管内物理吸附储氢进行了模拟。研究和讨论了5种半径的扶手椅管在T=300 K时的吸附等温线,给出了同一管径在不同压强下氢气分子在碳纳米管中分布变化的对比图,并对T=300 K,P=10 MPa时不同管径的碳纳米管储氢能力进行了对比。结果显示,常温下压强不大于10 MPa时单壁碳纳米管吸附氢气的质量储氢容量不超过1.8%,体积吸附量不超过22 kg.m-3,表明纯单壁碳纳米管具有一定的吸附氢气的能力,但其存储能力与美国能源部提出的研究目标尚有一定差距,还需通过改变碳纳米管的结构、特性等方法来改善其储氢特性。

GULP Simulation of Hydrogen Storage in Single-walled Carbon Nanotubes

The physisorption of hydrogen gas in the single-walled carbon nanotubes(SWNT) at T=300 K is simulated by using Monte Carlo method in GULP code.The adsorption isotherm of five armchair SWNTs with different radius at T=300 K was investigated.The distribution of hydrogen molecules in SWNT at different pressure is given when radius is fixed.The hydrogen storage capacity in carbon nanotubes of different diameters is compared for T=300 K,P=10 MPa.The results of calculation showed that at room temperature when the pressure is not greater than 10 MPa,the gravimetric density of hydrogen in SWNT is not more than 1.8% of the quality,and the volumetric adsorption capacity does not exceed 22 kg·m-3,All that shows that pure single-walled carbon nanotubes have a certain hydrogen adsorption capacity,while the storage capacity is not satisfactory,compar with the U.S.Department of Energy’s research goal.It needs some changes for the structure and features of carbon nanotubes to improve the hydrogen storage properties.