Boron-doped Graphene Research Articles

First Principles Calculations of Hydrogen Storage on Calcium-Decorated, Boron-Doped Bilayer Graphene

In this paper, the adsorption and storage of hydrogen on calcium-decorated, boron-doped bilayer graphene was investigated using first principles calculation. The calcium-decorated bilayer graphene was investigated and it was shown that the binding energy of H2 molecule adsorbed on the calcium-decorated bilayer graphene is −0.02 eV and the energy does not belong to reversible usage range of −0.2 - −0.6 eV. Substitutional boron doping can improve the adsorption energy of Ca to bilayer graphene with the empty pz orbital of boron atoms. Our calculations show that calcium atoms can be solidly adsorbed on the interlayer (Ca/B/Graphene) and outerlayer (2Ca/B/Graphene and 3Ca/B/Graphene) of B-doped bilayer graphene. Hydrogen molecule binds with Ca/B/Graphene, 2Ca/B/Graphene and 3Ca/B/Graphene system with an energy that belongs to reversible usage range of −0.2 - −0.6 eV. The overlap between Ca 3d and H2σ orbitals just below the Fermi energy demonstrates the charge transfer between the Ca atom and the H atom and the role of hybridization of the 3d orbita of Ca with the σ orbitals of H2 in efficient adsorption of hydrogen molecules. The charge from hydrogen bonding orbital transfers to empty 3d orbitals of the Ca atom, and then from the 3d orbitals of the Ca atom donated to H2σ* antibonding orbital. Hydrogen moleculars can be adsorbed on the interlayer and outerlayer of Ca-decorated B-doped bilayer graphene.

Theoretical study of the CO, NO, and N2 adsorptions on Li-decorated graphene and boron-doped graphene

The adsorption properties of common gas molecules (CO, NO, and N2) on the surface of Li-decorated pristine graphene and Li-decorated boron doped graphene are investigated using density functional theory. The adsorption energy, charge transfer, and density of states of gas molecules on three surfaces have been calculated and discussed, respectively. The results show that Li-decorated pristine graphene has strong interaction with CO and N2. Compared with Li-decorated pristine graphene, Li-decorated boron doped graphene exhibit a comparable adsorption ability of CO and N2. Moreover, Li-decorated boron doped graphene have a more significant adsorption energy to NO than that of Li-decorated pristine graphene because of the chemical interaction of the NO gas molecule. The strong interaction between the NO molecule and substrate (Li-decorated boron doped graphene) induces dramatic changes to the electrical conductivity of Li-decorated boron doped graphene. The results indicate that Li-decorated boron doped graphene would be an excellent candidate for sensing NO gas.

Boron-doped graphene as a metal-free catalyst for gas-phase oxidation of benzyl alcohol to benzaldehyde.

Boron-doped graphene samples (BGs) with tunable boron content of 0–2.90 at% were synthesized and directly used in the gas-phase oxidation of benzyl alcohol to benzaldehyde, and showed excellent performance. XPS results indicated that the graphitic sp2 B species (BC3) is the mainly boron dopant species incorporated in the graphene lattice, which could significantly improve the content of ketone carbonyl groups (C Created by potrace 1.16, written by Peter Selinger 2001-2019 ]]> O) on the graphene. For instance, the contents of CO jumped from 1.93 to 4.19 at% while BC3 doped into the graphene lattice was only 0.35 at%. The CO is the active site of catalytic reaction, so BG has significantly improved catalytic activity. Compared to the un-doped graphene (G), the conversion of benzyl alcohol over BGs increased 2.35 times and the selectivity of benzaldehyde increased from 77.3% to 99.2%. Aerobic–anaerobic exchange experiments revealed that the superior catalytic performance of BG was achieved only under aerobic conditions. The study of the boron-doped carbocatalyst may also provide guidance for the design of surface modified carbon-based catalysts for the selective oxidation dehydrogenation of alcohols by regulating doping elements and their types.

Boron-doped graphene as a promising electrocatalyst for NO electrochemical reduction: a computational study

The B-doped graphene is a quite promising metal free electrocatalyst for NO reduction to N2O and NH3.

Boron Doped Graphene Oxide: Synthesis and Application to Glucose Responsive Reactivity

Boron Doped Graphene Oxide: Synthesis and Application to Glucose Responsive Reactivity

Boron-doped graphene quantum dot/Ag–LaFeO3 p–p heterojunctions for sensitive and selective benzene detection

Benzene imprinting and compositing with BGQDs give Ag–LaFeO3 both high selectivity and low operating temperature to benzene.

Engineering nanoscale p–n junctionviathe synergetic dual-doping of p-type boron-doped graphene hybridized with n-type oxygen-doped carbon nitride for enhanced photocatalytic hydrogen evolution

A 2D–2D p–n junction heterointerface is formulated through the synergetic dual doping of boron-doped rGO and oxygen-doped gC3N4.

Ruthenium oxide modified hierarchically porous boron-doped graphene aerogels as oxygen electrodes for lithium-oxygen batteries.

Suitable catalysts and reasonable structures for oxygen electrodes can effectively improve the electrochemical performance of lithium–oxygen batteries. In this work, ruthenium oxide modified boron-doped hierarchically porous reduced graphene aerogels (RuO2-B-HRG) are prepared by a sol–gel and subsequent low temperature annealing method and used as oxygen electrodes. The RuO2 nanoparticles (5–10 nm) are uniformly anchored in the three-dimensional B-HRG continuous electric network. The RuO2-B-HRG aerogel possesses a large specific surface area (287.211 m2 g−1) and numerous mesopores and micropores. The pores facilitate electrolyte impregnation and oxygen diffusion, and they provide greatly increased accommodation space for the discharge products. Electrochemical tests show that the RuO2-B-HRG/KB enables the electrode overpotential to decrease, and the rate capability and the cycling stability are enhanced compared with pure HRG. The enhanced performance is ascribed to the bifunctional catalytic activity of RuO2-B-HRG and its unique three-dimensional porous architecture. The method is proved to be an effective strategy to combine porous carbon materials and nanoscale catalysts as electrodes for Li–O2 batteries.

Electrochemical and electrocatalytic reaction characteristics of boron-incorporated graphenevia a simple spin-on dopant process

Boron-doped graphene flakes prepared by a facile and relatively low-temperature spin-on dopant process exhibit superior pseudo-capacitive and oxygen reduction activity.

Boron-doped graphene nanosheet-supported Pt: a highly active and selective catalyst for low temperature H2-SCR.

A series of boron-doped graphene-supported Pt (Pt/BG) nanosheets were designed and synthesized using a one-step facile hydrothermal method. ICP, XPS, and TPD results confirmed that boron atoms were successfully embedded into the graphene matrix. The selective catalytic reduction of nitric oxide with hydrogen (H2-SCR) was tested over Pt/BG catalysts. The multi-roles of doped-boron were investigated by Raman, BET, CO-chemisorption, H2-TPD, XPS, and NO-TPD. Boron doping led to a higher dispersion and smaller size of Pt nanoparticles, facilitated hydrogen spillover, promoted more metallic Pt formation, and increased both H2 and NO chemisorption, which were attributed to an enhanced Pt nucleation rate over doped-boron, electron donation from boron to Pt, and extra chemisorption sites. The reaction performances (conversion 94.7%, selectivity 90.3%, and TOF 0.092 s-1) were greatly promoted attributing to a bifunctional catalytic mechanism. This work paves the way to modify the structure and tune the chemisorption ability of graphene-based catalysts, and provides novel insights for designing high performance catalysts.

Methanol decomposition reactions over a boron-doped graphene supported Ru-Pt catalyst.

The decomposition of methanol is currently attracting research attention due to the potential widespread applications of its end products. In this work, density functional theory (DFT) calculations have been performed to investigate the adsorption and decomposition of methanol on a Ru-Pt/boron doped graphene surface. We find that the most favorable reaction pathway is methanol (CH3OH) decomposition through O-H bond breaking to form methoxide (CH3O) as the initial step, followed by further dehydrogenation steps which generate formaldehyde (CH2O), formyl (CHO), and carbon monoxide (CO). The calculations illustrate that CH3OH and CO groups prefer to adsorb at the Ru-top sites, while CH2OH, CH3O, CH2O, CHO, and H2 groups favor the Ru-Pt bridge sites, indicating the preference of Ru atoms to adsorb the active intermediates or species having lone-pair electrons. Based on the results, it is found that the energy barrier for CH3OH decomposition through the initial O-H bond breaking is less than its desorption energy of 0.95 eV, showing that CH3OH prefers to undergo decomposition to CH3O rather than direct desorption. The study provides in-depth theoretical insights into the potentially enhanced catalytic activity of Ru-Pt/boron doped graphene surfaces for methanol decomposition reactions, thereby contributing to the understanding and designing of an efficient catalyst under optimum conditions.

Effect of boron doping level on the photocatalytic activity of graphene aerogels

Heteroatom-doped three-dimensional (3D) graphene-based macroscopic assemblies (GMAs) are receiving considerable attention for application as heterogeneous photocatalysts. However, the relationship between the concentration and the bonding state of heteroatoms at the atomic scale and the resulting photoelectronic and photocatalytic properties of 3D GMAs remain unexplored. Herein, we describe a simple, environmentally benign, one-pot hydrothermal reduction-induced self-assembly process to prepare boron-doped graphene aerogels by using graphene oxide and boric acid as carbon (C) and boron (B) sources, respectively. By rationally adjusting the dopant elemental precursor, the B content was modulated from ∼0.14 to ∼3.37 at%. The as-synthesized B-doped bulk graphene monoliths with well-defined interconnected 3D porous networks can effectively degrade acridine orange (AO), a well-known recalcitrant and biologically toxic pollutant, under visible light irradiation. Particularly, the aerogel with a moderate B loading of ∼2.15 at% displayed a superior photodegradation efficiency of ∼98%, which is 2.13 times higher than the undoped material. The generation of oxygenated B derivatives, such as borinic esters and boronic acids, on the edge sites and defect regions of the 2D graphene building blocks was primarily responsible for the exceptional photocatalytic activity. Besides, these macroscale photocatalysts are highly stable and easily recyclable for practical applications.

One-pot environment-friendly synthesis of boron doped graphene-SnO2 for anodic performance in Li ion battery

High specific capacity, availability of tin oxide (SnO2) and improved electrical conductivity and rate capability of boron-doped graphene sheets (BG) promises the composite of the two as a potential anode material for Li ion battery. We report for the first time, one-pot synthesis of SnO2 dispersed boron-doped few layer graphene (SnO2/BG-I) in an environment friendly, hazardous-harmful reducing agent free, hydrogen assisted reduction technique in comparison to complicated two-step conventional process. In addition, a two-step, wet chemical free, greener approach is also employed to achieve SnO2 nanoparticles over BG support (SnO2/BG-II). Both the materials as anode showed enhanced performance compared to un-doped graphene supported SnO2 nanoparticles (SnO2/G). One-pot synthesized SnO2/BG-I as anode in Li ion battery shows comparable performance with a reversible capacity of 348 mAh g−1 at a current density 200 mA g−1, while SnO2/BG-II with higher amount of boron doping, exhibits higher stability over cycles with an excellent reversible capacity of 558 mAh g−1 due to the uniform distribution of SnO2 over boron-doped graphene sheets.

Interlayer Coupling Behaviors of Boron Doped Multilayer Graphene

It is fundamentally important to understand how the interlayer interaction of neighboring graphene sheets is influenced by chemical doping. Here we investigate the interlayer coupling of multilayer graphene doped with controlled boron content via the Raman-active in-plane shear mode. The experimental results reveal a remarkable decline in the interlayer shear modulus as boron content increases, which is a direct consequence of the enlarged interlayer spacing, further supported by the molecular dynamic (MD) simulations. Nanoindentation tests were conducted to clarify the influence of interlayer coupling behaviors on nanomechanical behaviors of boron-doped bilayer graphene. As the interlayer slippage is induced under shear deformations, the weakened shear resistance would lead to the reduced energy dissipation during sliding process. Our results provide valuable insight into fundamental mechanical properties of boron-doped graphene and its interfaces and potentially allows tailoring of interlayer coupling f...

Boron-Doped Graphene as a Promising Anode Material for Potassium-Ion Batteries with a Large Capacity, High Rate Performance, and Good Cycling Stability

Potassium-ion batteries (KIBs), as alternatives to lithium-ion batteries (LIBs), have attracted increasing attention due to the abundance of K in the Earth’s crust. Here, using first-principles calculations, we have found that boron (B)-doped graphene is a promising anode material for KIBs. The studied B4C28 structure has a large specific capacity of 546 mAh/g, a small migration barrier of 0.07 eV, and a moderate potassiation voltage of 0.82 V to suppress the formation of a SEI layer. Moreover, B-doped graphene with a doping concentration of 12.5 at. % is metallic with good electron conductivity that can improve rate performance. Also, B doping makes the substrate electron-deficient and results in significant charge transfer from K to the substrate, thus preventing K atoms from clustering, inhibiting dendrite growth, and leading to a good cycling stability.

Enhanced Manifold of States Achieved in Heterostructures of Iron Selenide and Boron-Doped Graphene

Enhanced superconductivity is sought by employing heterostructures composed of boron-doped graphene and iron selenide. Build-up of a composite manifold of near-degenerate noninteracting states formed by coupling top-of-valence-band states of FeSe to bottom-of-conduction-band states of boron-doped graphene is demonstrated. Intra- and intersubsystem excitons are explored by means of density functional theory in order to articulate a normal state from which superconductivity may emerge. The results are discussed in the context of electron correlation in general and multi-band superconductivity in particular.

CVD Synthesis and Functionalization of Boron-Doped Graphene

We report in this paper the development of Boron-doped Graphene via chemical vapor deposition (CVD) that can serve as an efficient metal-free electrocatalyst for hydrogen evolution reaction (HER) in both alkaline and acidic media. Graphene growth is carried out by the flow of methane and hydrogen gasses, and with a borazine precursor over Ni foil and foam substrates at atmospheric pressure. The characterization is performed with scanning electron microscopy (SEM/EDS) and Raman/AFM spectroscopy. Electrochemical characterization of HER is performed by cyclic voltammetry (CV) measurements in 1 M KOH and 1M H2SO4 respectively, at room temperature, and 10 mV s–1 scan rate. Electrochemical tests are performed with an in-house designed cell with 1 cm2 surface area. The catalytic activity towards the HER of catalysts is determined from Tafel plots obtained from galvanostatic current-voltage measurements.

Synthesis of a Doubly Boron-Doped Perylene through NHC-Borenium Hydroboration/C-H Borylation/Dehydrogenation.

Reaction of an N-heterocyclic carbene (NHC)-borenium ion with 9,10-distyrylanthracene forms four B-C bonds through two selective, tandem hydroboration-electrophilic C-H borylations to yield an isolable, crystallographically characterizable polycyclic diborenium ion as its [NTf2 ]- salt (1). Dehydrogenation of 1 with TEMPO radical followed by acidic workup yields a 3,9-diboraperylene as its corresponding borinic acid (2). This sequence can be performed in one pot to allow the facile, metal-free conversion of an alkene into a small molecule containing a boron-doped graphene substructure. Doubly boron-doped perylene 2 exhibits visible range absorbance and fluorescence in chloroform solution (Φ=0.63) and undergoes two reversible one-electron reductions at moderate potentials of -1.30 and -1.64 eV vs. ferrocenium/ferrocene in DMSO. Despite sterically accessible boron centers and facile electrochemical reductions, compound 2 is air-, moisture-, and silica gel-stable.

Bottom up synthesis of boron-doped graphene for stable intermediate temperature fuel cell electrodes

The high surface area and electrical conductivity of few-layered graphene would make it an ideal catalyst support and electrode in fuel cells apart from its susceptibility to oxidative corrosion. Here we report the single-step, bottom-up synthesis of oxidation-resistant boron-doped graphene and show its increased stability in the aggressive electrochemical environment of intermediate temperature solid acid fuel cells (SAFCs). Boron was shown to alter the growth mode of single walled carbon nanohorns by laser vaporization to produce high yields of thin (<20 layer) boron-doped (2–3 at.%) crystalline flakes of turbostratic graphene (B-GLF). Alternatively, adding partial pressures of hydrogen less effectively shifted the growth mode of SWCNHs toward planar, turbostratic graphene-like flakes (GLFs). Thermogravimetric analysis indicates that boron-doping enhances the oxidation resistance of few-layer GLFs by >140 °C, with large fractions of multilayered B-GLFs surviving 10 °C/min ramps to 1000 °C. These B-GLFs provided a stable Pt catalyst support and electrode over 40 h operation in SAFCs with cesium dihydrogen phosphate electrolyte operating at 250 °C, as opposed to undoped GLFs or SWCNHs which were nearly completely consumed. The facile synthesis and oxidation-resistant properties of boron-doped GLF appear promising for graphene applications in oxidizing environments.

Boron doping effect on the interface interaction and mechanical properties of graphene reinforced copper matrix composite

In order to explore an efficient way of modifying graphene to improve the Cu/graphene interfacial bonding and remain the excellent mechanical and physical properties of graphene, the interaction between Cu and the pristine, atomic oxygen functionalized and boron- or nitrogen-doped graphene with and without defects was systematically investigated by density functional theory calculation. The electronic structure analysis revealed that the chemically active oxygen can enhance the binding energy Eb of Cu with graphene by forming strong covalent bonds, supporting the experimental study suggesting an vital role of intermediate oxygen in the improvement of the mechanical properties of graphene/Cu composites. Due to the strong hybridization between Cu-3d electron states and the 2p states of both boron and carbon atoms, the boron-doping effect is comparable to or even better than the chemical bridging role of oxygen in the reduced graphene oxide reinforced Cu matrix composite. Furthermore, we evidenced an enhancement of mechanical properties including bulk modulus, shear modulus and Young modulus of graphene/Cu composite after boron doping, which closely relates to the increased interfacial binding energy between boron-doped graphene and Cu surfaces.