An Ab-initio study of the Y decorated 2D holey graphyne for hydrogen storage application

Abstract

Expanding pollution and rapid consumption of natural reservoirs (gas, oil, and coal) led humankind to explore alternative energy fuels like hydrogen fuel. Solid-state hydrogen storage is most desirable because of its usefulness in the onboard vehicle. In this work, we explored the yttrium decorated ultra porous, two-dimensional holey-graphyne for hydrogen storage. Using the first principles DFT simulations, we predict that this system can adsorb up to seven hydrogen molecules per yttrium atom resulting in a gravimetric hydrogen weight percentage of 9.34, higher than the target of 6.5 wt% set by the US Department of Energy (DoE). The average binding energy per H2 and desorption temperature comes out to be -0.33 eV and ~ 428 K, respectively, very much suitable for fuel cell application. Yttrium atom is bonded strongly on HGY sheet due to charge transfer from Y 4d orbital to C 2p orbital whereas the adsorption of H2 molecule on Y is due to Kubas-type of interactions involving charge donation from H 1s orbital to Y 3d orbital and back donation with net charge gain by H 1s orbital. Furthermore, sufficient energy barriers for the metal atom diffusion have been found to prevent the clustering of transition metal (yttrium) on HGY sheet. The stability of the system at a higher temperatures is analyzed using Ab-initio molecular dynamics (AIMD) method, and the system is found to be stable at room and the highest desorption temperature. Stability of the system at higher temperatures, presence of adequate diffusion energy barrier to prevent metal-metal clustering, high gravimetric wt% of H2 uptake with suitable binding energy, and desorption temperature signifies that Y doped HGY is a promising material to fabricate high capacity hydrogen storage devices.

Ca Functionalization of the Polyaramid System for Reversible Hydrogen Storage: A DFT Study

“…SWCNT + Y could hold up to 10 H 2 molecules, as reported by Chakraborty et al , The binding energies of nine H 2 molecules on zirconium adsorbed graphene and Y-decorated graphene were −0.34 and −0.3 eV, respectively. , When Zr was introduced to the 4–6–8 biphenylene sheets, the adsorption energy was −0.4 eV . Sc-decorated graphene could store five H 2 molecules with a binding energy of −0.36 eV, while Y-decorated holey-graphene has a binding energy of −0.34 eV for seven H 2 molecules. , Triazine-based graphitic carbon nitride on Sc and Zr adsorption could adsorb seven H 2 molecules with binding energies of −0.39 and −0.38 eV, respectively, with weight % values of 8.62 and 7.1, respectively. , Metal clustering is a possibility in transition-metal (TM)-decorated carbon nanomaterials due to their high cohesive energies, even though TM-decorated carbon nanomaterials can adsorb numerous hydrogen atoms on a single metal via Kubas interactions . On the other hand, alkali metals and alkali earth metals (AEMs) have a comparatively lower cohesive energy, and thus, the possibility of clustering is less.…”

“…22 Scdecorated graphene could store five H 2 molecules with a binding energy of −0.36 eV, while Y-decorated holey-graphene has a binding energy of −0.34 eV for seven H 2 molecules. 28,29 Triazine-based graphitic carbon nitride on Sc and Zr adsorption could adsorb seven H 2 molecules with binding energies of −0.39 and −0.38 eV, respectively, with weight % values of 8.62 and 7.1, respectively. 30,31 Metal clustering is a possibility in transitionmetal (TM)-decorated carbon nanomaterials due to their high cohesive energies, even though TM-decorated carbon nanomaterials can adsorb numerous hydrogen atoms on a single metal via Kubas interactions.…”

2D BN-biphenylene: structure stability and properties tenability from a DFT perspective

“…One of the most trusted methods to ensure the stability of theoretically predicted materials is to compute the phonon dispersion spectra with no imaginary frequency. 42 Similar to cohesive energy methods, phonon spectra are also calculated for 0D, 70 1D 71 and 2D, 58,72 and 3D 73 materials to ensure their stability. In the case of more than zero-dimensional materials, phonon spectra are calculated along a suitable path joining selected high symmetry points in their Brillouin zone.…”

“…75 Molecular dynamics stability. AIMD simulations examine the higher temperature stability of all dimensional materials, as reported in the previous literature for 0D, 76,77 1D, 78 2D, 72,79 and 3D 80 materials. So, we created a 2 Â 2 Â 1 supercell for our system and performed AIMD simulation in two steps: First, employing a microcanonical ensemble (NVE) at each step of 1 fs for 5 ps, we raised the temperature of BN-BPh up to 300 K. Second, we performed AIMD in the canonical ensemble (NVT) using the Nose Hoover thermostat to keep the temperature of BN-BPh constant for 5 ps with steps of 1 fs.…”

Pristine and transition metal decorated holey graphyne monolayer as an ammonia sensor: insights from DFT simulations

“…Enormous surface area and uniformly distributed voids offer remarkable stability and extended surface activity. Though the first principles calculation of HGY for hydrogen storage and catechol detection has been reported, the theoretical investigation of HGY as a gas sensor is still unexplored [37][38][39].…”