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Hydrogen adsorption in multi-walled boron nitride nanotubes and their arrays was studied using grand canonical Monte Carlo simulation. The results show that hydrogen storage increases with tube diameter and the distance between the tubes in multi-walled boron nitride nanotube arrays. Also, triple-walled boron nitride nanotubes present the lowest level of hydrogen physisorption, double-walled boron nitride nanotubes adsorb hydrogen better when the diameter of the inner tube diameter is sufficiently large, and single-walled boron nitride nanotubes adsorb hydrogen well when the tube diameter is small enough. Boron nitride nanotube arrays adsorb hydrogen, but the percentage of adsorbed hydrogen (by weight) in boron nitride nanotube arrays is rather similar to that found in multi-walled boron nitride nanotubes. Also, when the Langmuir and Langmuir-Freundlich equations were fitted to the simulated data, it was found that multi-layer adsorptivity occurs more prominently as the number of walls and the tube diameter increase. However, in single-walled boron nitride nanotubes with a small diameter, the dominant mechanism is monolayer adsorptivity.

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A novel 1D PbII coordination polymer containing Pb2‐(μ‐N3)2 unit [Pb(dmp)(N3)2]n (dmp =  2,9‐dimethyl‐1,10‐phenanthroline) has been prepared and characterized. Single‐crystal X‐ray diffraction analyses show that the coordination number for PbII ions is six, PbN6, with “stereochemically active” electron lone pairs and the coordination sphere being hemidirected. The single‐crystal X‐ray data show the chains interact with each other through the π–π stacking interactions, which create a 3D framework. The structure of title complex has been optimized by density functional theory. Structural parameters and IR spectra for the complex are in agreement with the crystal structure.

in SWSiCNTs. Also, the excess and delivery isotherms of hydrogen were calculated for various SWSiCNTs, SWBNNTs and SWCNTs. Furthermore, the adsorption selectivity in different mole fractions of hydrogen/methane and hydrogen/nitrogen mixtures in SWSiCNTs has investigated at 77 and 298 K on (8,8) and (15,15) SWSiCNTs, and results show that selectivity-based adsorption decreases at 298 K in both mixtures while increasing pressure and temperature can increase selectivities and the selectivity is not related to the diameter of nanotubes.