ИСТИНА

Carbon nanotubes (CNT) are promising materials for adsorption storage of methane and hydrogen [1]. At the same time, an arrangement of nanotubes into ordered arrays, such as triangular packages, leads significant increase of adsorption capacity of these materials [2-3]. At the present work a possibility of formation of supramolecular structures from carbon nanotubes (diameter about 1 nm and length about 5 nm) and coordinate molecules – cyclic and aromatic hydrocarbons (cyclopentane C5H10, cyclohexane C6H12, ethyl cyclopentane C7H14, benzene C6H6, isopropyl benzene С9Н12, naphthalene C10H8) was studied by numerical simulation based on molecular dynamics method. The simulation was implemented in microcanonical ensemble (N, V, E) at constant temperatures in a range between 200 and 400 K and was based on physicochemical properties of the substance for coordination of nanotubes. It was shown that the molecules of cyclic and aromatic hydrocarbons separate nanotubes from each over and orient them mainly into triangular array. Such parameters as number of adsorbed substance molecules and temperature of the experiment, required for self-organization of carbon nanotubes into arrays, depend on physicochemical properties of the adsorbate. It was revealed that the molecules of cyclic and aromatic hydrocarbons were arranged primarily perpendicularly to the surface of nanotubes. Consequently, dimensions of hydrocarbon coordinate molecules correlate to distances between nanotubes in array. Created model supramolecular structures possessed following gaps between nanotubes, determined as distances between geometrical centers of nanotubes, nm: CNT/ C5H10 – 1.8, CNT/C6H12 – 2.0, CNT /C7H14 – 1.9, CNT /C6H6 – 1.9(5), CNT /С9Н12 – 2.1, CNT /C10H8 – 2.2. Step by step removal of coordinate molecules from the system by portions from 5 to 50 pcs, depending on overall amount of nanotubes in the array, leads to development of the porosity between nanotubes without destruction of the space structure (fig. 1). This additional nanoporosity can be used storage of such important gases as methane and hydrogen.