Electronic structure investigation of biphenylene films

Evidence of hybridization states at the donor/acceptor interface: case ofm-MTDATA/PPT

We performed a spectroscopic study on them-MTDATA (donor) and PPT (acceptor) molecular vertical heterostructure. The electronic properties of the donor/acceptor interface have been comprehensively characterized by synchrotron radiation-based photoelectron spectroscopy and near-edge x-ray absorption fine structure. The spectroscopic results reveal the existence of new hybridization states in the original molecular energy gap, likely attributed to the interaction between the donor and the acceptor molecules at the interface. Such hybridized states can have a significant impact on the charge transport in organic electronic devices based on donor-acceptor molecules and can explain the increased efficiency of device using such molecules.

Spectroscopic Evidence of New Low-Dimensional Planar Carbon Allotropes Based on Biphenylene via On-Surface Ullmann Coupling

The bottom-up synthesis and preliminary characterizations of a new biphenylene-based 2D framework are presented. This new low-dimensional carbon allotrope potentially completes the many hypothesized carbon networks based on biphenylene.

Multicomponent gas separation and purification using advanced 2D carbonaceous nanomaterials

Multicomponent gas separation and purification is an important pre- or post-processing step in industry. Herein, we employed a multiscale computational approach to investigate the possibility of multicomponent low-weight gas (H₂, O₂, N₂, CO₂, CH₄) separation and purification using novel porous 2D carbonaceous nanomaterials, namely Graphdiyne (GD), Graphenylene (GN), and Rhombic-Graphyne (RG). The dispersion-corrected plane-wave density functional theory (DFT) calculation combined with the Climbing Image Nudged Elastic Band (CI-NEB) method was employed to study the gas/membrane interaction energy and diffusion barrier of different gases passing through the geometrically optimized membranes. The results from CI-NEB calculations were then fitted to the Morse potential function to construct a bridge between quantum mechanics calculations and non-equilibrium molecular dynamics (NEMD) simulation. The selectivity of each membrane for all binary mixtures was calculated using the estimated diffusion energy barriers based on the Arrhenius equation. Finally, a series of extensive NEMD simulations were carried out to evaluate the real word and time dependent separation process. According to the results, CH₄ molecules can be completely separated from the other gases using a GD membrane, O₂ molecules from CH₄, N₂, and CO₂ by a GN membrane, and H₂ molecules from all other gases using a RG membrane.

Piezoelectric Response of Porous Nanotubes Derived from Hexagonal Boron Nitride under Strain Influence

A computational study via periodic density functional theory of porous nanotubes derived from single-layer surfaces of porous hexagonal boron nitride nanotubes (PBNNTs) and inorganic graphenylene-like boron nitride nanotubes (IGP-BNNTs) has been carried out with the main focus in its piezoelectric behavior. The simulations showed that the strain provides a meaningful improve in the piezoelectric response on the zigzag porous boron nitride nanotubes. Additionally, its stability, possible formation, elastic, and electronic properties were analyzed, and for comparison purpose, the porous graphene and graphenylene nanotubes were studied. From the elastic properties study, it was found that IGP-BNNTs exhibited a higher rigidity because of the influence of the superficial porous area, as compared to PBNNTs. The present study provides evidence that the strain is a way to maximize the piezoelectric response and make this material a good candidate for electromechanical devices.