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Advancement toward opening a bandgap at the Dirac point induced by symmetry breaking paved the way to realize 2D heterostructures with graphene and hexagonal boron nitride (h-BN). An alternate arrangement of graphene and h-BN layers in a 3D stacking can tune the bandgaps of these composites depending on the position of B and N atoms with respect to C atoms of graphene. Herein, a unique possibility of arranging graphene and h-BN atomic layers in a quasiperiodic Fibonacci sequence to study the possibilities of controlling the electronic properties of these heterostructures is explored. Density functional theory calculations combined with van der Waals corrections reveal that these quasiperiodic heterostructures are more stable than normal periodic stacking of monolayers of graphene and h-BN. Moreover, for certain arrangements of atomic layers, sizeable bandgaps can be obtained.

Advancement toward opening a bandgap at the Dirac point induced by symmetry breaking paved the way to realize 2D heterostructures with graphene and hexagonal boron nitride (h-BN). An alternate arrangement of graphene and h-BN layers in a 3D stacking can tune the bandgaps of these composites depending on the position of B and N atoms with respect to C atoms of graphene. Herein, a unique possibility of arranging graphene and h-BN atomic layers in a quasiperiodic Fibonacci sequence to study the possibilities of controlling the electronic properties of these heterostructures is explored. Density functional theory calculations combined with van der Waals corrections reveal that these quasiperiodic heterostructures are more stable than normal periodic stacking of monolayers of graphene and h-BN. Moreover, for certain arrangements of atomic layers, sizeable bandgaps can be obtained.

Advancement toward opening a bandgap at the Dirac point induced by symmetry breaking paved the way to realize 2D heterostructures with graphene and hexagonal boron nitride (h-BN). An alternate arrangement of graphene and h-BN layers in a 3D stacking can tune the bandgaps of these composites depending on the position of B and N atoms with respect to C atoms of graphene. Herein, a unique possibility of arranging graphene and h-BN atomic layers in a quasiperiodic Fibonacci sequence to study the possibilities of controlling the electronic properties of these heterostructures is explored. Density functional theory calculations combined with van der Waals corrections reveal that these quasiperiodic heterostructures are more stable than normal periodic stacking of monolayers of graphene and h-BN. Moreover, for certain arrangements of atomic layers, sizeable bandgaps can be obtained.

Advancement toward opening a bandgap at the Dirac point induced by symmetry breaking paved the way to realize 2D heterostructures with graphene and hexagonal boron nitride (h-BN). An alternate arrangement of graphene and h-BN layers in a 3D stacking can tune the bandgaps of these composites depending on the position of B and N atoms with respect to C atoms of graphene. Herein, a unique possibility of arranging graphene and h-BN atomic layers in a quasiperiodic Fibonacci sequence to study the possibilities of controlling the electronic properties of these heterostructures is explored. Density functional theory calculations combined with van der Waals corrections reveal that these quasiperiodic heterostructures are more stable than normal periodic stacking of monolayers of graphene and h-BN. Moreover, for certain arrangements of atomic layers, sizeable bandgaps can be obtained.

Advancement toward opening a bandgap at the Dirac point induced by symmetry breaking paved the way to realize 2D heterostructures with graphene and hexagonal boron nitride (h-BN). An alternate arrangement of graphene and h-BN layers in a 3D stacking can tune the bandgaps of these composites depending on the position of B and N atoms with respect to C atoms of graphene. Herein, a unique possibility of arranging graphene and h-BN atomic layers in a quasiperiodic Fibonacci sequence to study the possibilities of controlling the electronic properties of these heterostructures is explored. Density functional theory calculations combined with van der Waals corrections reveal that these quasiperiodic heterostructures are more stable than normal periodic stacking of monolayers of graphene and h-BN. Moreover, for certain arrangements of atomic layers, sizeable bandgaps can be obtained.

LnPO(4)center dot 0.667H(2)O rhabdophane has been considered as a potential material for the precipitation of actinides from radioactive waste liquid, owing to its outstanding characteristics of high actinide bearing and easy synthesis in acid solutions. However, a comprehensive understanding of the actinide occupation and the precipitation response of rhabdophane to remove actinides has yet to be established. In this study, the effect of ions concentration and pH values on the detailed precipitation reaction of CexNd1-xPO4 center dot 0.667H(2)O rhabdophane in acid solutions are systematically investigated. Some specific issues such as structural distortion and flexibility, and occupation mechanism are discussed by combining with experiments and density functional theory (DFT) calculation. The results reveal that ions concentration and pH values have a significant impact on the crystallization nucleation step before 12 h. The obtained removal rate of Nd3+ is more than 99% in pH 1-5 solutions with the ions concentration of 0.05-0.1 mol/L. Moreover, incorporating Nd in CePO4 center dot 0.667H(2)O rhabdophane will easily result in the lattice distortion in b-axis. DFT calculation and X-ray photoelectron spectroscopy (XPS) results reveal that Nd is preferentially incorporated in nonhydrated site to form a weaker binding energy of NdO8 polyhedron.

Effective techniques for the detection of selected viruses detection of their amino acids (AAs) constituents are highly desired, especially in the present COVID pandemic. Motivated by this, we have used density functional theory (DFT) simulations to explore the potential applications of green phosphorene monolayer (GPM) as efficient nanobio-sensor. We have employed van der Waals induced calculations to study the ground-state geometries, binding strength, electronic structures, and charge transfer mechanism of pristine, vacancy-induced and metal-doped GPM to detect the selected AAs, such as glycine, proline and aspartic, in both aqueous and non-aqueous media. We find that the interactions of studied AAs are comparatively weak on pristine (-0.49 to -0.76 eV) and vacancy-induced GPM as compared to the metal-doped GPM (-0.62 to -1.22 eV). Among the considered dopants, Ag-doping enhances the binding of AAs to the GPM stronger than the others. In addition to appropriate binding energies, significant charge transfers coupled with measurable changes in the electronic properties further authenticate the potential of GPM. Boltzmann thermodynamic analysis have been used to study the sensing mechanism under varied conditions of temperatures and pressure for the practical applications. Our findings signify the potential of G PM based sensors towards efficient detection of the selected AAs.

Effective techniques for the detection of selected viruses detection of their amino acids (AAs) constituents are highly desired, especially in the present COVID pandemic. Motivated by this, we have used density functional theory (DFT) simulations to explore the potential applications of green phosphorene monolayer (GPM) as efficient nanobio-sensor. We have employed van der Waals induced calculations to study the ground-state geometries, binding strength, electronic structures, and charge transfer mechanism of pristine, vacancy-induced and metal-doped GPM to detect the selected AAs, such as glycine, proline and aspartic, in both aqueous and non-aqueous media. We find that the interactions of studied AAs are comparatively weak on pristine (-0.49 to -0.76 eV) and vacancy-induced GPM as compared to the metal-doped GPM (-0.62 to -1.22 eV). Among the considered dopants, Ag-doping enhances the binding of AAs to the GPM stronger than the others. In addition to appropriate binding energies, significant charge transfers coupled with measurable changes in the electronic properties further authenticate the potential of GPM. Boltzmann thermodynamic analysis have been used to study the sensing mechanism under varied conditions of temperatures and pressure for the practical applications. Our findings signify the potential of G PM based sensors towards efficient detection of the selected AAs.

Effective techniques for the detection of selected viruses detection of their amino acids (AAs) constituents are highly desired, especially in the present COVID pandemic. Motivated by this, we have used density functional theory (DFT) simulations to explore the potential applications of green phosphorene monolayer (GPM) as efficient nanobio-sensor. We have employed van der Waals induced calculations to study the ground-state geometries, binding strength, electronic structures, and charge transfer mechanism of pristine, vacancy-induced and metal-doped GPM to detect the selected AAs, such as glycine, proline and aspartic, in both aqueous and non-aqueous media. We find that the interactions of studied AAs are comparatively weak on pristine (-0.49 to -0.76 eV) and vacancy-induced GPM as compared to the metal-doped GPM (-0.62 to -1.22 eV). Among the considered dopants, Ag-doping enhances the binding of AAs to the GPM stronger than the others. In addition to appropriate binding energies, significant charge transfers coupled with measurable changes in the electronic properties further authenticate the potential of GPM. Boltzmann thermodynamic analysis have been used to study the sensing mechanism under varied conditions of temperatures and pressure for the practical applications. Our findings signify the potential of G PM based sensors towards efficient detection of the selected AAs.

Effective techniques for the detection of selected viruses detection of their amino acids (AAs) constituents are highly desired, especially in the present COVID pandemic. Motivated by this, we have used density functional theory (DFT) simulations to explore the potential applications of green phosphorene monolayer (GPM) as efficient nanobio-sensor. We have employed van der Waals induced calculations to study the ground-state geometries, binding strength, electronic structures, and charge transfer mechanism of pristine, vacancy-induced and metal-doped GPM to detect the selected AAs, such as glycine, proline and aspartic, in both aqueous and non-aqueous media. We find that the interactions of studied AAs are comparatively weak on pristine (-0.49 to -0.76 eV) and vacancy-induced GPM as compared to the metal-doped GPM (-0.62 to -1.22 eV). Among the considered dopants, Ag-doping enhances the binding of AAs to the GPM stronger than the others. In addition to appropriate binding energies, significant charge transfers coupled with measurable changes in the electronic properties further authenticate the potential of GPM. Boltzmann thermodynamic analysis have been used to study the sensing mechanism under varied conditions of temperatures and pressure for the practical applications. Our findings signify the potential of G PM based sensors towards efficient detection of the selected AAs.

Effective techniques for the detection of selected viruses detection of their amino acids (AAs) constituents are highly desired, especially in the present COVID pandemic. Motivated by this, we have used density functional theory (DFT) simulations to explore the potential applications of green phosphorene monolayer (GPM) as efficient nanobio-sensor. We have employed van der Waals induced calculations to study the ground-state geometries, binding strength, electronic structures, and charge transfer mechanism of pristine, vacancy-induced and metal-doped GPM to detect the selected AAs, such as glycine, proline and aspartic, in both aqueous and non-aqueous media. We find that the interactions of studied AAs are comparatively weak on pristine (-0.49 to -0.76 eV) and vacancy-induced GPM as compared to the metal-doped GPM (-0.62 to -1.22 eV). Among the considered dopants, Ag-doping enhances the binding of AAs to the GPM stronger than the others. In addition to appropriate binding energies, significant charge transfers coupled with measurable changes in the electronic properties further authenticate the potential of GPM. Boltzmann thermodynamic analysis have been used to study the sensing mechanism under varied conditions of temperatures and pressure for the practical applications. Our findings signify the potential of G PM based sensors towards efficient detection of the selected AAs.

Atomic design of a 2D-material such as graphene can be substantially influenced by etching, deliberately induced in a transmission electron microscope. It is achieved primarily by overcoming the threshold energy for defect formation by controlling the kinetic energy and current density of the fast electrons. Recent studies have demonstrated that the presence of certain species of atoms can catalyze atomic bond dissociation processes under the electron beam by reducing their threshold energy. Most of the reported catalytic atom species are single atoms, which have strong interaction with single-layer graphene (SLG). Yet, no such behavior has been reported for molecular species. This work shows by experimentally comparing the interaction of alkali and halide species separately and conjointly with SLG, that in the presence of electron irradiation, etching of SLG is drastically enhanced by the simultaneous presence of alkali and iodine atoms. Density functional theory and first principles molecular dynamics calculations reveal that due to charge-transfer phenomena the C-C bonds weaken close to the alkali-iodide species, which increases the carbon displacement cross-section. This study ascribes pronounced etching activity observed in SLG to the catalytic behavior of the alkali-iodide species in the presence of electron irradiation.

Atomic design of a 2D-material such as graphene can be substantially influenced by etching, deliberately induced in a transmission electron microscope. It is achieved primarily by overcoming the threshold energy for defect formation by controlling the kinetic energy and current density of the fast electrons. Recent studies have demonstrated that the presence of certain species of atoms can catalyze atomic bond dissociation processes under the electron beam by reducing their threshold energy. Most of the reported catalytic atom species are single atoms, which have strong interaction with single-layer graphene (SLG). Yet, no such behavior has been reported for molecular species. This work shows by experimentally comparing the interaction of alkali and halide species separately and conjointly with SLG, that in the presence of electron irradiation, etching of SLG is drastically enhanced by the simultaneous presence of alkali and iodine atoms. Density functional theory and first principles molecular dynamics calculations reveal that due to charge-transfer phenomena the C-C bonds weaken close to the alkali-iodide species, which increases the carbon displacement cross-section. This study ascribes pronounced etching activity observed in SLG to the catalytic behavior of the alkali-iodide species in the presence of electron irradiation.

Atomic design of a 2D-material such as graphene can be substantially influenced by etching, deliberately induced in a transmission electron microscope. It is achieved primarily by overcoming the threshold energy for defect formation by controlling the kinetic energy and current density of the fast electrons. Recent studies have demonstrated that the presence of certain species of atoms can catalyze atomic bond dissociation processes under the electron beam by reducing their threshold energy. Most of the reported catalytic atom species are single atoms, which have strong interaction with single-layer graphene (SLG). Yet, no such behavior has been reported for molecular species. This work shows by experimentally comparing the interaction of alkali and halide species separately and conjointly with SLG, that in the presence of electron irradiation, etching of SLG is drastically enhanced by the simultaneous presence of alkali and iodine atoms. Density functional theory and first principles molecular dynamics calculations reveal that due to charge-transfer phenomena the C-C bonds weaken close to the alkali-iodide species, which increases the carbon displacement cross-section. This study ascribes pronounced etching activity observed in SLG to the catalytic behavior of the alkali-iodide species in the presence of electron irradiation.

Single atom catalysts (SACs) present the ultimate level of catalyst utilization, which puts them in the focus of current research. Using density functional theory calculations, model SACs consisting of nine metals (Ni, Cu, Ru, Rh, Pd, Ag, Ir, Pt, and Au) on four different supports (pristine graphene, N- and B-doped graphene and graphene with single vacancy) are analyzed. Only graphene with a single vacancy enables the formation of SACs, which are stable in terms of aggregation and dissolution under electrochemical conditions. Reactivity of models SACs is probed using atomic (hydrogen and A = C, N, O, and S) and molecular adsorbates (AH(x), x = 1, 2, 3, or 4, depending on A). Scaling relations between adsorption energies of A and AH(x) on model SACs are confirmed. However, the scaling is broken for CH3. There is also an evident scaling between adsorption energies of atomic and molecular adsorbates on metals SAs supported by pristine, N-doped and B-doped graphene, which originates from similar electronic structures of SAs on these supports. Using the obtained data, the authors analyze the hydrogen evolution on the model SACs. Only M@graphene vacancy systems (excluding Ag and Au) are stable under hydrogen evolution conditions in highly acidic solutions.

Atomic design of a 2D-material such as graphene can be substantially influenced by etching, deliberately induced in a transmission electron microscope. It is achieved primarily by overcoming the threshold energy for defect formation by controlling the kinetic energy and current density of the fast electrons. Recent studies have demonstrated that the presence of certain species of atoms can catalyze atomic bond dissociation processes under the electron beam by reducing their threshold energy. Most of the reported catalytic atom species are single atoms, which have strong interaction with single-layer graphene (SLG). Yet, no such behavior has been reported for molecular species. This work shows by experimentally comparing the interaction of alkali and halide species separately and conjointly with SLG, that in the presence of electron irradiation, etching of SLG is drastically enhanced by the simultaneous presence of alkali and iodine atoms. Density functional theory and first principles molecular dynamics calculations reveal that due to charge-transfer phenomena the C-C bonds weaken close to the alkali-iodide species, which increases the carbon displacement cross-section. This study ascribes pronounced etching activity observed in SLG to the catalytic behavior of the alkali-iodide species in the presence of electron irradiation.

Atomic design of a 2D-material such as graphene can be substantially influenced by etching, deliberately induced in a transmission electron microscope. It is achieved primarily by overcoming the threshold energy for defect formation by controlling the kinetic energy and current density of the fast electrons. Recent studies have demonstrated that the presence of certain species of atoms can catalyze atomic bond dissociation processes under the electron beam by reducing their threshold energy. Most of the reported catalytic atom species are single atoms, which have strong interaction with single-layer graphene (SLG). Yet, no such behavior has been reported for molecular species. This work shows by experimentally comparing the interaction of alkali and halide species separately and conjointly with SLG, that in the presence of electron irradiation, etching of SLG is drastically enhanced by the simultaneous presence of alkali and iodine atoms. Density functional theory and first principles molecular dynamics calculations reveal that due to charge-transfer phenomena the C-C bonds weaken close to the alkali-iodide species, which increases the carbon displacement cross-section. This study ascribes pronounced etching activity observed in SLG to the catalytic behavior of the alkali-iodide species in the presence of electron irradiation.

Graphite anode have shown commercial success for over two decades, since the start of their use in commercial Li-ion batteries, due to their high practical specific capacity, conductivity, and low lithiation potential. Graphite is to a large extent thermodynamically unfavorable for sodium-ion intercalation and thus limits advancement in Na-ion batteries. In this work, a beta-phase arsenic-phosphorus monolayer is studied, which has recently been predicted to have semiconducting behavior and to be dynamically stable. First-principles calculations based on density functional theory are used to explore the role of beta-AsP monolayer as a negative electrode for Na-ion batteries. Cohesive energy, phonon spectrum, and molecule dynamics simulations confirm the thermodynamic stability and the possibility of experimentally synthesizing this material. The Na-ion adsorption-energies are found to be high (>-1.2 eV) on both sides (As- and P-side). The ultra-fast energy barriers for Na (0.046/0.053 V) over both sides imply high diffusion of Na-ions on the surfaces of beta-AsP. During the evaluation of Na-ion anode performance, the fully sodiated state is found to be Na2AsP, which yields a high theoretical-specific capacity of 506.16 mAh g(-1)and low average sodiation potential of 0.43 V versus Na/Na+.

Wheat straw-derived carbon from the Wheatbelt region in Western Australia was subjected to chemical activation in an electrolyte containing either acid or base treatment. The findings showed an increase in electron/hole mobility towards the interfaces due to the presence of different surface functional groups such as C-SOx-C and S=C in the carbon framework for acid activation. Likewise, the galvanostatic capacitance measured at a current density of 2 mA cm(-2) in a three-electrode configuration for acid-activated wheat straw exhibited 162 F g(-1), while that for base-activated wheat straw exhibited 106 F g(-1). An increase of 34.5 % more capacitance was achieved for acid-treated wheat straw. This improvement is attributed to the synergistic effects between surface functional groups and electrolyte ions, as well as the electronic structure of the porous electrode.

Wheat straw-derived carbon from the Wheatbelt region in Western Australia was subjected to chemical activation in an electrolyte containing either acid or base treatment. The findings showed an increase in electron/hole mobility towards the interfaces due to the presence of different surface functional groups such as C-SOx-C and S=C in the carbon framework for acid activation. Likewise, the galvanostatic capacitance measured at a current density of 2 mA cm(-2) in a three-electrode configuration for acid-activated wheat straw exhibited 162 F g(-1), while that for base-activated wheat straw exhibited 106 F g(-1). An increase of 34.5 % more capacitance was achieved for acid-treated wheat straw. This improvement is attributed to the synergistic effects between surface functional groups and electrolyte ions, as well as the electronic structure of the porous electrode.

Wheat straw-derived carbon from the Wheatbelt region in Western Australia was subjected to chemical activation in an electrolyte containing either acid or base treatment. The findings showed an increase in electron/hole mobility towards the interfaces due to the presence of different surface functional groups such as C-SOx-C and S=C in the carbon framework for acid activation. Likewise, the galvanostatic capacitance measured at a current density of 2 mA cm(-2) in a three-electrode configuration for acid-activated wheat straw exhibited 162 F g(-1), while that for base-activated wheat straw exhibited 106 F g(-1). An increase of 34.5 % more capacitance was achieved for acid-treated wheat straw. This improvement is attributed to the synergistic effects between surface functional groups and electrolyte ions, as well as the electronic structure of the porous electrode.

Wheat straw-derived carbon from the Wheatbelt region in Western Australia was subjected to chemical activation in an electrolyte containing either acid or base treatment. The findings showed an increase in electron/hole mobility towards the interfaces due to the presence of different surface functional groups such as C-SOx-C and S=C in the carbon framework for acid activation. Likewise, the galvanostatic capacitance measured at a current density of 2 mA cm(-2) in a three-electrode configuration for acid-activated wheat straw exhibited 162 F g(-1), while that for base-activated wheat straw exhibited 106 F g(-1). An increase of 34.5 % more capacitance was achieved for acid-treated wheat straw. This improvement is attributed to the synergistic effects between surface functional groups and electrolyte ions, as well as the electronic structure of the porous electrode.

Wheat straw-derived carbon from the Wheatbelt region in Western Australia was subjected to chemical activation in an electrolyte containing either acid or base treatment. The findings showed an increase in electron/hole mobility towards the interfaces due to the presence of different surface functional groups such as C-SOx-C and S=C in the carbon framework for acid activation. Likewise, the galvanostatic capacitance measured at a current density of 2 mA cm(-2) in a three-electrode configuration for acid-activated wheat straw exhibited 162 F g(-1), while that for base-activated wheat straw exhibited 106 F g(-1). An increase of 34.5 % more capacitance was achieved for acid-treated wheat straw. This improvement is attributed to the synergistic effects between surface functional groups and electrolyte ions, as well as the electronic structure of the porous electrode.