Effects of Ir and B co-doping on H2 adsorption properties of armchair carbon nanotubes using Optical Spectra Analysis for energy storage

Abstract

In this research, DFT+U approach was used to investigate the performance of Iridium (Ir) and Boron (B) co-doped armchair (8, 8) Single-walled Carbon Nanotube (SWCNT). Calculations of the structural electronic and optical spectra analysis of the system under study were carried out using the ab’initio quantum simulations implemented in Quantum ESPRESSO and thermo_pw codes within the popular density functional theory. In the doping process, carbon atoms have been replaced by Ir and B atoms in the SWCNT, the investigations were done on the basis of distance of H2 (d) from the co-doped SWCNT at intervals of 6.12 Å, 6.45 Å and 6.77Å, variations of temperature, variations of external electric field, band gaps, optical adsorptions and binding energy variations were all taken in to account. It is found that Ir/B co-doping in pristine SWCNT significantly enhanced the H2 adsorption capacity of the SWCNT. Furthermore, an increase in temperature decrease the performance ability of the co-doped SWCNT, negative adsorptions intensities were recorded by temperature increase by 650, 700 and 750 0C, this can be termed as exothermic adsorption. Therefore it can be demonstrated that H2 by co-doped SWCNT undergoes endothermic adsorption under ambient temperature and shows exothermic adsorption under higher temperatures.

The potentials of boron-doped (nitrogen deficient) and nitrogen-doped (boron deficient) BNNT photocatalysts for decontamination of pollutants from water bodies

“…The efficiency rate of photocatalysts depends on their light absorption properties which are dependent on the imaginary dielectric constant. 20 We define the optical response of photocatalyst materials to the incident solar radiation in terms of the real and imaginary dielectrics as 21 ε ( ω ) = ε 1 ( ω ) + ε 2 ( ω ) where ε 1 ( ω ) is the real part and ε 2 ( ω ) is the imaginary part of the optical dielectric constant. The real part of the dielectric function takes care of the photon energy dispersion, while the imaginary part of the dielectric function describes the photon energy absorption.…”

Tuning the potentials of aluminum phosphide nanotube photocatalyst for wastewater treatment through band gap engineering: a DFT study

“…DFT calculations are considered best for the prediction of photocatalytic properties of nanosystems because of their ability to provide information on microscopic processes such as charge transfer, reactant adsorption and absorption, surface reactions and also product desorption. In this way, core electrons were investigated by the pseudopotential method while electronic wave functions were determined by the plane wave method [24]. The exchange-correlation in terms of Perdew-Burke-Ernzerhof (PBE) was used for the generalized gradient approximation to treat ionic interactions.…”