Mono Vacancy Research Articles

Effects of Vacancies and Nitrogen Dopants on Interfacial Bonding and Electronic Structure of Graphene/Metal Composites

The vacancies and nitrogen dopants significantly alter the interfacial bonding and electrical properties at the graphene/metal interface. The graphene/copper system, characterized by coherent and immiscible interfaces, serves as a suitable benchmark to elucidate the intrinsic interactions between carbon and metal atoms. Herein, the individual effects of vacancies and nitrogen dopants, as well as their combined effects, are systematically investigated. The bonding energies show that the interfacial bonding is the strongest at the monovacancy (MV) graphene/copper interface, indicating that the introduction of nitrogen in defective graphene/copper interfaces weakens the interfacial bonding. Furthermore, the band structures indicate that both vacancies and nitrogen dopants contribute to the formation of a bandgap. Among them, both MV and graphitic nitrogen doping significantly enhance interfacial bonding while maintaining relatively intact interfacial and band structures.

Adsorbtive removal of HF toxic gas via tinsulfide monolayer modification: A molecular perspective

Hydrofluoric Acid (HF) is considered one of the most hazardous chemicals used in industrial plants. Even small exposures to HF can have fatal consequences if not promptly and properly treated. Various research teams have presented numerous substances with the objective of capturing or detecting toxic HF gas. In this study, we explore the impact of HF gas on a single layer of SnS by employing density functional theory (DFT). The interaction nature between the gas molecule and the adsorbent is elucidated by analyzing the related adsorption energy, electronic structure properties and differential charge transfer. The findings indicate that HF is physically adsorbed on the pristine SnS with an adsorption energy value of −0.63 eV. By introducing a Sn mono vacancy defect, the modification of SnS enhances the adsorption energy to −1.26 eV, resulting in a chemisorption process. Molecular fluorine (F2) was discovered to undergo a barrierless reaction with SnS, resulting in the formation of fluorine-substituted SnS. It has been discovered that the substitution of fluorine atoms enhances the reactivity of SnS towards hydro-gen fluoride gas. The adsorption potential of the studied structures towards HF gas was determined to be in the following order: F2SnS > VSn–SnS > VS-SnS ∼ SnS. The current study is anticipated to offer new molecular insights that could lead to the creation of innovative devices for detecting or eliminating HF toxic gas from a specific atmosphere.

A striking exploration of defect engineering in HfS2, HfSe2, and janus HfSSe through ab initio analysis for HER catalysis application

The present study emphasizes the enhancement in catalytic activity due to the formation of vacancies using dispersion corrected density functional theory. We observed that without vacancy formation, in general the edge site is an active site for hydrogen adsorption, while the lowest Gibbs free energy (ΔGH) is found to be for Janus HfSSe at the S-edge site. Furthermore, interestingly, due to the hindrance of the edge site, it facilitates only the Volmer-Heyrovsky reaction rather than the Volmer-Tafel. Among the mono vacancies, the Hafnium mono vacancy shows the lowest adsorption energy.We observed a competition between the evolution of H2S and H2 gas in the case of HfS2-VHf, whereas in the case of defected Janus and HfSe2, due to the presence of Se layers, we observed no competitiveness with H2S or H2Se gas with hydrogen gas. These defected materials exhibit lower reactional Gibbs free energy than a pristine monolayer due to its metallic nature. We observed that Hafnium vacancy enhances the HER activity, and pave the way for dominating Volmer-Heyrovsky reaction.

Point defects in Dirac semimetal BeN[formula omitted] monolayer and their interaction with gas molecules

Point defects in materials may occur during the fabrication process of monolayer materials, or these defects can be created via electron beam irradiation to the perfect crystals. Recently, a triclinic phase of beryllium tetranitride BeN4 was synthesized from elements at ∼85 GPa pressure and can become a monolayer under ambient conditions. In this study, we have introduced various point defects into the BeN4 monolayer such as Be or N mono vacancy (Bevac, Nvac), BeN divacancy (BeNvac), antisite defect of BeN atomic positions and Stone–Wales (SW) defect, and investigated electronic and magnetic changes in the material. It is found that with the Be vacancy, the Dirac cone of the BeN4 monolayer disappears and the Bevac monolayer shows semi-metallic properties with overlapping valence and conduction bands. N vacancy induces local magnetic moment (0.797 μB) to the structure, and the Nvac monolayer has a direct band gap value of 0.172 eV. While the BeN divacancy turns the structure to metal, the antisite-defected BeN4 monolayer turns into a non-magnetic semiconductor with a band gap value of 0.256 eV. Furthermore, we have introduced bare and defected BeN4 monolayers with CO, CO2, H2, H2O and O2 gas molecules and found that these molecules give rise to crucial effects on the electronic and magnetic properties of the materials. While the considered molecules are physisorbed on the bare BeN4 monolayer, the H2O molecule dissociated to OH and H on the Nvac structure, and O2 molecule strongly binds on Nvac and antisite BeN4 monolayers. Furthermore, we have reported that the antisite BeN4 monolayer may be a good candidate material for hydrogen storage devices with an adsorption energy of 0.355 eV of the H2 molecule. We believe that our theoretical findings will be beneficial for further experimental and theoretical studies on BeN4 structure.

Improvement of the ability of graphene by simultaneous cobalt (Co) and nitrogen (N) doping as an electrode for supercapacitor application

Thanks to its high electronic conductance and large surface, many research studies have investigated the application of graphene (Gr) in supercapacitors as an electrode material. The properties of Gr can change efficiently through the doping of specific elements and by designing various morphologies. In the current piece of research, DFT calculations are undertaken to investigate the impact of doping cobalt (Co) and nitrogen (N) atoms, and a monovacancy (MV)-added Gr structure upon the quantum capacitance (QC), electronic attributes and stability. Based on the calculations, doping Co and N and the presence of the MV radically changed the QC of the electrode. Nevertheless, achieving structural stability can be a challenge. A high QC of ∼77 μF/cm2 was obtained in the CoN3 system by the association of N-doping and the existence of the MV. The present piece of research provides insights into the viable impact of combined doping upon increasing the QC of Gr-based electrodes.

First-principles study of sodium adsorption on defective graphene under propylene carbonate electrolyte conditions.

Hard carbon (HC) has been predominantly used as a typical anode material of sodium-ion batteries (SIBs) but its sodiation mechanism has been debated. In this work, we investigate the adsorption of Na atoms on defective graphene under propylene carbonate (PC) and water solvent as well as vacuum conditions to clarify the sodiation mechanism of HC. Within the joint density functional theory framework, we use the nonlinear polarizable continuum model for PC and the charge-asymmetric nonlocally-determined local electric solvation model for water. Our calculations reveal that the centre of each point defect such as mono-vacancy (MV), di-vacancy (DV) and Stone-Wales is a preferable adsorption site and the electrolyte enhances the Na adsorption through implicit interaction. Furthermore, we calculate the formation energies of multiple Na atom arrangements on the defective graphene and estimate the electrode potential versus Na/Na+, verifying that the multiple Na adsorption on the MV and DV defective graphene under the PC electrolyte conditions is related to the slope region of the discharge curve in HC. This reveals new prospects for optimizing anodes and electrolytes for high performance SIBs.

First-Principles Study of Adsorption of Methane on Defective Silicene

Considering the significance of natural gas, such as methane, and the difficulties in storing it, research is increasingly focusing on developing materials for solid-state methane storage. Two-dimensional materials have a large number of possible adsorption sites for gas molecules due to their high surface-to-volume ratio. However, the two-dimensional structure is chemically inactive and attracts nonpolar gases rather weakly. We investigated the methane gas adsorption capabilities of silicene by activating it with different defects. According to our density functional theory calculations, the mono-vacancy (MV) defect is advantageous in increasing the binding strength of energy-carrying gases such as methane. In MV defective silicene, methane adsorption energy is detected in the order of the internationally specified energy regime.

Investigation of unified impact of Ti adatom and N doping on hydrogen gas adsorption capabilities of defected graphene sheets

In this work, we studied the hydrogen adsorption capabilities of functionalized graphene sheets containing a variety of defects (D-G) via molecular dynamics (MD) simulations that govern the mechanisms involved in hydrogen adsorption. Specifically, the graphene sheets containing monovacancy (MV), Stone-Wales (SW), and multiple double vacancy (DV) defects were functionalized with Ti and N atoms to enhance their hydrogen adsorption capacity. We measured the adsorption capacities of the N-/D-G sheets with varying concentrations of Ti adatoms at 300 K and 77 K temperatures and various pressures. Our study revealed that the increasing concentration of Ti adatoms on the D-G sheets led to a significant improvement in the hydrogen adsorption capacity of the graphene sheets. The DV(III)-G sheets showed the maximum adsorption capacity at 300 K because the DV(III)-G sheets had a small number of large-sized pores that bind hydrogen with high binding energy. Thus, hydrogen remained adsorbed even at higher temperatures (300 K). The N doping on the D-G sheets initially reduced their hydrogen adsorption capabilities; however, the N-D-G sheets enhanced their hydrogen adsorption capacity with the increasing concentrations of Ti adatoms. Compared to all other defect types, the Ti–N-DV(III)-G sheet with a Ti concentration of 10.5% showed a hydrogen uptake of 5.5 wt% at 300 K and 100 bar pressure. Thus, the N doping and Ti implantations improved the hydrogen storage capabilities of the graphene sheets, and these findings helped design solid-state hydrogen storage systems operating at ambient conditions and moderate pressure ranges.

Structural modification and band gap engineering of carbon nano-onions via sulphur doping: Theoretical DFT study

Density functional theory (DFT) calculations were performed to investigate the structures and electronic properties of S-doped carbon nano-onions (S-CNOs). We report a detailed study of the stoichiometric and defective (monovacancy (MV) and divacancy (DV)) CNOs with different doping contents and distribution patterns. The results indicate the natural tendency of sulphur to occur in groups around the edges of the local deformations and at the defects that are in very good qualitative agreement with the experimental data. [22] More importantly, the five-membered rings containing disulphide bridges are the most stable binding motif in the structure of CNOs. However, the S-S motif can also be located in the six-membered ring either with both two-coordinated S atoms or with one- and three-fold coordinated S atoms. For defective systems, we also studied the energetic stability of the MV- and DV-containing S-CNOs. The results reveal that the most stable position of sulphur is the two-fold coordinated carbon site in the first case, whereas in the second case, it is the one linking octagonal and pentagonal rings. Furthermore, the electronic analysis indicates that the position and concentration of dopant and the type of defect unambiguously influence the band gap energy in both stoichiometric and defective CNOs.

Strain tunable quantum emission from atomic defects in hexagonal boron nitride for telecom-bands

This study presents extending the tunability of 2D hBN Quantum emitters towards telecom (C-band − 1530 to 1560 nm) and UV-C (solar blind − 100 to 280 nm) optical bands using external strain inducements, for long- and short-range quantum communication (Quantum key distribution (QKD)) applications, respectively. Quantum emitters are the basic building blocks of this QKD (quantum communication or information) technologies, which need to emit single photons over room temperature and capable of tuning the emission wavelength to the above necessary range. Recent literature revealed that quantum emitters in 2D hBN only has the ability to withstand at elevated temperatures and aggressive annealing treatments, but density functional theory (DFT) predictions stated that hBN can only emit the single photons from around 290 to 900 nm (UV to near-IR regions) range. So, there is a need to engineer and further tune the emission wavelength of hBN quantum emitters to the above said bands (necessary for efficient QKD implementation). One of the solutions to tune the emission wavelength is by inducing external strain. In this work, we examine the tunability of quantum emission in hBN with point defects by inducing three different normal strains using DFT computations. We obtained the tunability range up to 255 nm and 1589.5 nm, for the point defects viz boron mono vacancies (VB) and boron mono vacancies with oxygen atoms (VBO2) respectively, which can enhance the successful implementation of the efficient QKD. We also examine the tunability of the other defects viz. nitrogen mono vacancies, nitrogen mono vacancy with self-interstitials, nitrogen mono vacancy with carbon interstitials, carbon dimers and boron dangling bonds, which revealed the tunable quantum emission in the visible, other UV and IR spectrum ranges and such customized quantum emission can enhance the birth of other quantum photonic devices.

Topological defects embedded large-sized single-walled carbon nanotubes for hydrogen storage: A molecular dynamics study

In this paper, we investigate the performance of large-sized single-walled carbon nanotubes (SWCNTs) incorporated with mono vacancy (MV), double vacancy (DV), and Stone-Wales (SW) topological defects as a medium for hydrogen adsorption using molecular dynamics (MD) simulations. A novel potential energy distribution (PED) method is employed with MD simulations to determine the adsorbed hydrogen molecules and associated binding energy. In addition, we extended our work to bundles of defected SWCNT (D-SWCNT) that provided the most prominent adsorption capacity subjected to temperature and pressure variations. In particular, four representative (8,8), (13,13), (19,19), and (33,0) SWCNTs are simulated under various thermodynamic conditions, and collected adsorption isotherms data reveals higher gravimetric density for large-sized SWCNT. At 77 K and 100 bar, the maximum hydrogen uptake in pristine SWCNTs is 6.88–7.73 wt%, depending on the size of the nanotubes. In contrast, the binding energy decreases as the nanotube size increases. At 77 K, (8,8) and (19,19) SWCNTs have average binding energies of 0.043 and 0.021 eV, respectively. Meanwhile, (19,19) SWCNT incorporated with 1% DV defects having 5–8 rings (DV1) and MV defects yields the maximum storage capacity of 9.07 wt% and 8.62 wt%, respectively, at 77 K. Furthermore, the increment of about 43.29% in wt.% is obtained for DV1 defected nanotube relative to pristine SWCNT at 300 K and 100 bar. Moreover, our results indicate the maximum hydrogen uptake of 8.65, 7.15, 2.57, and 1.33 wt% in the square array of DV1 defect embedded SWCNTs at 77, 100, 200, and 300 K, respectively, compared to 9.07, 6.65, 2.24, and 1.11 wt% in the isolated D-SWCNT at identical conditions. As a result, the D-SWCNT bundles are better suited for hydrogen storage at high temperatures than the isolated D-SWCNT. Our present study paves the way to progress toward the efficient usage of D-SWCNTs with few chemical alterations for scaled-up applications.

A combined experimental and theoretical study of small and large vacancy clusters in tungsten

Tungsten is considered to be used in the future fusion reactors as plasma-facing material. In such extreme environments, defects are induced in materials that modify their macroscopic properties such as the mechanical ones. It is of paramount importance to be able to determine concentration and size of the vacancy defects, from the mono vacancy to the large cavities, to validate the models developed to predict the evolution of the microstructure of irradiated materials. Positrons are very useful non-destructive probes that can characterize vacancy-type defects in materials. We present a combined experimental and theoretical study on detecting and estimating the sizes of vacancy clusters that are invisible with electron microscopy in tungsten, using positron annihilation spectroscopy. We here model the positron annihilation in the tungsten lattice and in vacancy-type defects using state-of-the-art first principles methodology. The Doppler broadening spectra and positron lifetimes in tungsten are calculated with two-component density functional theory with local density approximation and weighted density approximation. Our calculations are in excellent agreement with our experimental results. We show that the sizes of vacancy clusters in tungsten can be well estimated by combining both positron lifetimes and Doppler broadening spectra. We also determine the limit of validity of the canonical calculation method, which here is shown to fail when the vacancy clusters grow beyond their nucleation stage. This work is a first step needed to better interpret the measured positron annihilation characteristics (Doppler and lifetime) in tungsten and then extract quantitative data on small vacancy defects required to improve the understanding of early-stage vacancy defect evolution in tungsten. The method used in this paper could be used to study other metallic materials.

Effect of vacancy modification on the quantum capacitance of silicene- based electrode in efficient supercapacitors

In this study, we tried to evaluate the application of defected silicene as an electrode in supercapacitors using density functional theory calculations. Researchers have focused on single and double-vacancy silicene. In this work, we investigated six types of vacancies, namely the structures of mono vacancy (MV), double vacancy (DV), triple vacancy (TV), quadruple vacancy (QV), five vacancy (FV) and six vacancy (SV). The density of state, the integrated quantum capacitance, and stored charge plots for the pristine and the vacancy-modified defected silicene structures were investigated. Our results showed that using the vacancy-modified defected structures in the voltage range of -0.50 to 0.50 V provides more quantum capacities than using the pristine silicene. The vacancies MV, TV, QV, FV, and SV can be used as negative and positive electrodes, and they are p-type semiconductors. According to our calculations, the charge stored in at the vacancy-modified defected structures is higher than the charge stored in the pristine silicene at 0 to 0.5 V. The values of the charge stored in all of the vacancy-modified defected structures are similar to those in the pristine silicene. According to our results, the defected silicene is considered as a promising material in high-efficiency supercapacitors.

DFT exploration of adsorptive performances of borophene to small sulfur-containing gases.

Density functional theory (DFT) calculations were applied to study the ability of B36 to adsorb H2S, SO2, SO3, CH3SH, (CH3)2S, and C4H4S gases. Several exchange-correlation including B97D, PBE, B3LYP, M062X, and WB97XD were utilized to evaluate adsorption energies. The initial results showed that boundary boron atoms are the most appropriate interaction sites. The adsorption energies, electron density, electron localized function, and differential charge density plots confirmed the formation of chemical covalent bonds only between SOx and B36. The results of thermochemistry analysis revealed the exothermic nature of the adsorption of sulfur-containing gases on B36; the highest values of ∆H298 were found for SO3/B36 and SO2/B36 systems. The electronic absorption spectra and DOS of B36 did not exhibit significant variations after gases adsorption, while the modeled CD spectra showed a remarkable change in the case of the SOx/B36 system. Accordingly, B36 is not suggested for detecting the studied gases. The effect of imposing mono vacancy defect and external electric field to the adsorption of titled gases on the sorbent showed, while the former did not affect the adsorption energies significantly the later improved the adsorption of gas molecules on the B36 system. The results of the current study could provide deeper molecular insight on the removal of SOx gases by B36 system.

Defective GaAs nanoribbon-based biosensor for lung cancer biomarkers: a DFT study.

Density functional theory-based first-principles investigation is performed on pristine and mono vacancy induced GaAs nanoribbons to detect the presence of three volatile organic compounds (VOCs), aniline, isoprene and o-toluidine, which will aid in sensing lung cancer. The study has shown that pristine nanoribbon senses all three analytes. For the pristine structure, we observe decent adsorbing parameters and the bandgap widens after the adsorption of analytes. However, the introduction of the carrier traps induced by defect causes deep energy wells that vary the electrical properties as indicated in the bandgap analysis of GaAs, wherein adsorption of aniline and o-toluidine reduces the bandgap to 0eV, making the structure highly conductive in nature. The adsorption energies of defect-induced nanoribbon are more as compared with the pristine counterpart. Nonetheless, the introduction of defects has improved the sensitivity further.

Thermal behaviour, kinetics and mechanisms of CO2 interactions with graphene: An atomic scale reactive molecular dynamic study

Atomic scale understanding of gasification interactions between graphene and CO2 is presently very limited. Extensive reactive force field molecular dynamics simulation studies were carried out on interactions of pristine (Pr) and a monovacancy (MV) graphene with CO2 in the temperature range (4100–5000 K). Gasification kinetics showed a non-linear behaviour with temperature; abnormal thermal behaviour was observed in the intermediate (4200–4400 K) temperature region. Gasification rates were found to be substantially lower in this region due to the formation of relatively stable intermediate structures. Three stages were used to describe the whole reaction process. The first stage involved the formation of defects as 5-membered and 7-membered rings; carbon bonds near these defects tended to elongate or break forming voids or cavities. In the second stage, the carbon chains were broken by interaction with O or CO2, leading to the formation of carbonyl groups and active carbon sites with dangling bonds. In the third stage, a number of CO2 molecules or O atoms were adsorbed on the active carbon sites releasing CO and enhanced gasification. The presence of a monovacancy promoted reaction kinetics only at relatively low temperatures with little influence at higher temperatures.

Strain and defect engineering of graphene for hydrogen storage via atomistic modelling

The adsorption of hydrogen molecules on monolayer graphene is investigated using molecular dynamics simulations (MDS). Interatomic interactions of the graphene layer are described using the well-known AIREBO potential, while the interactions between graphene and hydrogen molecule are described using Lennard-Jones potential. In particular, the effect of strain and different point defects on the hydrogen storage capability of graphene is studied. The strained graphene layer is found to be more active for hydrogen and show 6.28 wt% of H2 storage at 0.1 strain at 77 K temperature and 10 bar pressure. We also studied the effect of temperature and pressure on the adsorption energy and gravimetric density of H2 on graphene. We considered different point defects in the graphene layer like monovacancy (MV), Stone Wales (SW), 5-8-5 double vacancy (DV), 555–777 DV, and 5555-6-7777 DV which usually occur during the synthesis of graphene. At 100 bar pressure, graphene with 1% concentration of MV defects leads to 9.3 wt% and 2.208 wt% of H2 storage at 77 K and 300 K, respectively, which is about 42% higher than the adsorption capacity of pristine graphene. Impact of defects on the critical stress and strain of defected graphene layers is also studied.

Thermal behaviour during initial stages of graphene oxidation: Implications for reaction kinetics and mechanisms

Atomic level understanding of graphene oxidation behaviour is presently far from complete. During large scale preparation of graphene from graphene oxide (GO), persistent presence of up to 8% residual oxygen is an issue of great concern. Such incomplete reduction is attributed to the presence of highly stable carbonyl and ether groups. Here we present a new approach for limiting the formation and behavior of these functional groups. We report high temperature molecular dynamics simulations on the oxidation process of pristine (Pr) and mono-vacancy (MV) graphene with O2 with specific focus on the initial reaction period. An abnormal thermal behaviour was observed in the onset times of oxidation reactions; significant differences were detected in the nucleation and growth mechanisms and reaction kinetics. Overall reaction kinetics was significantly slower in the thermal region (Pr: 4350–4450 K; MV: 4300–4450 K). By identifying this region experimentally or theoretically, a narrow window of minimal carbonyl group formation and residual oxygen could be created leading to a major breakthrough in the field.

Investigation of the mono vacancy effects on the structural, electronic and magnetic properties of graphene hexagonal-boron nitride in-plane hybrid embracing diamond shaped graphene island

The preparation of an atomically thin sheet of graphene/h-BN (GBN) hybrid with lack of defects is almost unachievable as in three dimensional crystals. Here, we first discussed the stability and electronic properties of GBN hybrid nanosheet which is formed by implanting a diamond shaped graphene (G) island into the hexagonal boron nitride (h-BN) layout. We further investigated the effects of mono vacancy on the electronic and magnetic properties of defective GBN nanosheet. The band gap of pristine hybrid decreases with growing G island as expected and the island induces flat (dispersionless) energy bands near the Fermi energy of the h-BN nanosheet. We searched for the energetics of 7 distinct C, B and N mono vacancies created at various places such as h-BN region, G region and interface of the optimized pristine hybrid. The G-BN interface is found as the energetically most favourable place for vacancy formation. Depending on the size of the graphene island, the C vacancy is the most favourable defect type in our DFT calculations. The N vacancy is energetically preferred over the B vacancy due to its lower formation energy with the exception of biggest G island. Although pristine hybrids are non-magnetic semiconductors, the GBN hybrid can become magnetic with a reasonable amount of magnetic moment depending on the type of vacancy and vacancy site. The vacancy defected hybrids also show the properties of semiconductor except for the hybrid involving the smallest size island with the B vacancy in the h-BN layout (VBL). Defected hybrids involving the smallest G island have the highest amount of band gaps due to high ratio of carbon atoms at the interface to the island interior. Accordingly, the band gap tends to decrease with expanding G island. However, the band gap of VBL defected structures broadens with increasing size of island interestingly. Moreover, this defected hybrid introduces the greatest amount of magnetic moment (3 μB) as the island expands. The C vacancies in the G island and around the N atom introduce a magnetic moment of 2 μB as the G island expands as well. The magnetic moment of the N vacancy defected hybrid is 1 μB irrespective of island size. The vacancy defect leads local in-plane/out-of-plane distortions rather than structural reconstructions in our calculations. In general, no correlation was observed between the island size and the magnetic moment of a defective hybrid.

Tuning the electronic and magnetic properties of pentagraphene through the C1 vacancy

Pentagraphene (PG), a two-dimensional allotrope of carbon with only five-membered rings, was recently predicted to exhibit a wide band gap, an unusual negative Poisson’s ratio, and robust dynamical and thermal stability. However, its potential properties arising from defect engineering of five-membered rings have not been explored yet. In this work, we explore the C1 vacancy in PG using first-principles density functional calculations. The formation energy of this vacancy is surprisingly within the formation energy window of monovacancy (MV) in graphene. This defect introduces eight midgap levels indicating the possibility of studying the charge states. The charged defect is amphoteric with deep donor and deep acceptor levels. Introducing the vacancy in the sheet renders it inherently ferromagnetic (FM) with a magnetic moment of 4 µB. Upon further investigating spin polarization in PG, three possible unique magnetic configurations are found to exist: FM, ferrimagnetic (FiM), and anti-ferromagnetic (AFM). The energy difference between the FM and the FiM (AFM) states is ∼−62.4 meV atom−1 (∼−81.9 meV atom−1). Despite FiM and AFM being lower in energy, interestingly, this intrinsic FM ordering of spins is preserved even when the defect concentration is increased. This observation would probably hint at the existence of a kinetic barrier between FM and AFM states which merits further investigations.