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Investigating the surface properties of heteroatom-doped carbon materials is essential because these versatile materials have found use in a variety of energy and environmental applications; an understanding of these properties would also lead to an improved appreciation of the direct interaction between the reactant and the functionalized surface. Herein, we explore the effect of boron (B) doping on the surface properties of activated carbon (AC) materials based on their water adsorption behavior and oxygen reduction reaction. In the high-temperature B doping process, B-doped AC materials at 1400 °C exhibit an open pore structure with B-O bonds, whereas at a temperature of 1600 °C, a nonporous structure containing a large amount of B-C bonds prevails. The B-O species act as active sites for water adsorption on the carbon surface. On the basis of the isothermal adsorption heat, we suggest that B atoms are present at the pore openings and on the surfaces. The B-O moieties at the open edges improve the electrocatalytic activity, whereas the B-C bonds at the closed edges decrease the electrocatalytic activity because of the stable structure of these bonds. Our findings provide new evidence for the electrocatalytic properties associated with the structure of B-doped edges.

The conversion of carbon dioxide (CO2) into high-value-added chemicals by photocatalysis is recognized as a potential method to ease the greenhouse effect and the global energy crisis simultaneousl...

The coupled adsorption–photocatalytic oxidation process provides a great potential scenario to enhance the removal efficiency of arsenite contaminants by converting As(III) to As(V) and simultaneou...

The development of thermoelectric (TE) materials, which can directly convert waste heat into electricity, is vital to reduce the use of fossil fuels. Mg2Sn and Mg2Si are promising TE materials beca...

The nickel-rich cathode LiNi0.6Co0.1Mn0.3O2 (NCM613) is a promising cathode material but has poor cycle stability, especially at a high cutoff voltage. Aiming at modulating the unit cell parameters...

Facile conversion of CO2 into useful multicarbon products is of broad interest in the field of energy storage and controllable carbon emission. However, electrochemical CO2 reduction to ethanol on ...

Partially positive-charged copper (Cuδ+) is known to boost the formation of highly valued multicarbon C2+ products during the electrochemical CO2 reduction reaction (CO2RR). In this work, we doped ...

Bulk turbostratic graphitic carbon of varying levels of disorder and chemical compositions has been synthesized by a direct synthesis method in the temperature range of 750–1100 °C, with a focus on...

One-pot synthesis of a new doubly boron-doped polycyclic aromatic hydrocarbon of 6,12-dimesityl-6,12-dihydro-6,12-diboradibenzo[def,mno]chrysene (MDBDBC) was reported. MDBDBC features a rigid planar electron-deficient core structure and demonstrates good chemical and thermal stabilities. A low-lying LUMO of -3.53 eV, a low locally excited triplet energy of 1.92 eV, as well as green electroluminescence with maximum EQE of 4.9% were found for MDBDBC, suggesting its potential as an n-type unit for future organic light emitting diode applications.

We study the oxygen reduction reaction (ORR) mechanism on the neighboring active sites of a B-doped pyrolyzed Fe–N–C catalyst using a combination of density functional theory-based calculations and...

We demonstrate the synthesis of double-walled carbon nanotubes (DWNTs) with a selectively boron-doped outer tube via the thermal diffusion method. Such selective boron-doping in the outer tubes alt...

We report a detailed experimental and theoretical study on thermoelectric properties of boron-doped single-walled carbon nanotubes (B-SWCNTs), which are versatile building blocks of flexible thermoelectric devices. Implantations of substitutional boron dopants (0.1-0.5 atom %) in SWCNTs are realized using thermal diffusion. The after-synthesis boron doping simultaneously improves the Seebeck coefficient (S) and electrical conductivity (s) of SWCNT networks, leading to an S2s value of 226 mW/mK2. First-principle calculations indicate that a few tenths atom % of substitutional boron atoms improve the S value of semi-conducting SWCNTs but reduce the electron conductance in individual SWCNTs. The high s of B-SWCNT networks is attributed to the improved electrical transport between laterally contacted metallic and semi-conducting nanotubes. The produced B-SWCNTs are stable over high-temperature annealing or processing in liquid media, which inspired us to fabricate thermoelectric modules by a low-cost printing method. The modules demonstrate an increased thermoelectric efficiency by 76% compared to those with undoped SWCNTs. This work provides a feasible fabrication strategy and physical insights for B-SWCNT-based flexible thermoelectrics.

SiOx-based anode materials with high capacity and outstanding cycling performance have gained numerous attentions. Nevertheless, the poor electrical conductivity and non-negligible volume change hi...

Ammonia is one of the most important industrial chemicals due to its wide application in various fields. However, its synthesis requires heavy energy consumption and harsh reaction conditions. Here...

Linear annulation of two 2,3-biphenylenediyl moieties to a 1,4-dibora-2,5-cyclohexadiene core via its carbon atoms leads to the boron-doped phenylene-containing oligoacene (B-POA) DBI. The optoelec...

Silicon (Si) attracts extensive attention as the advanced anode material for lithium (Li)-ion batteries (LIBs) because of its ultrahigh Li storage capacity and suitable voltage plateau. Hollow porous structure and dopant-induced lattice expansion can enhance the cycling stability and transporting kinetics of Li ions. However, it is still difficult to synthesize the Si anode possessing these structures simultaneously by a facile method. Herein, the lightly boron (B)-doped spherical hollow-porous Si (B-HPSi) anode material for LIBs is synthesized by a facile magnesiothermic reduction from B-doped silica. B-HPSi exhibits local lattice expansion located on boundaries of refined subgrains. B atoms in Si contribute to the increase of the conductivity and the expansion of lattices. On the basis of the first-principles calculations, the B dopants induce the conductivity increase and local lattice expansion. As a result, B-HPSi electrodes exhibit a high specific capacity of ∼1500 mAh g

NH3 synthesis almost relies on the energy-intensive Haber–Bosch process with abandoned CO2 emission. Electrochemical N2 reduction offers an environmentally friendly process for sustainable artifici...

We report that metal ions (M: Sn4+ and Ti4+) and boron-codoped hematite photoanodes with an n–n+ homojunction showed significantly increased photoelectrochemical (PEC) water splitting activity with...

Boron-doped and defect-engineered graphene aerogels are prepared using triphenyl boron as a boron precursor and subsequent heat treatments. The boron chemistry and concentration in the graphene lat...

B-doped diamond has become the ultimate material for applications in the field of microelectromechanical systems (MEMS), which require both highly wear resistant and electrically conductive diamond films and microstructures. Despite the extensive research of the tribological properties of undoped diamond, to date there is very limited knowledge of the wear properties of highly B-doped diamond. Therefore, in this work a comprehensive investigation of the wear behavior of highly B-doped diamond is presented. Reciprocating sliding tests are performed on micro- and nanocrystalline diamond (MCD, NCD) films with varying B-doping levels and thicknesses. We demonstrate a linear dependency of the wear rate of the different diamond films with the B-doping level. Specifically, the wear rate increases by a factor of 3 between NCD films with 0.6 and 2.8 at. % B-doping levels. This increase in the wear rate can be linked to a 50% decrease in both hardness and elastic modulus of the highly B-doped NCD films, as determined by nanoindentation measurements. Moreover, we show that fine-grained diamond films are more prone to wear. Particularly, NCD films with a 3× smaller grain size but similar B-doping levels exhibit a double wear rate, indicating the crucial role of the grain size on the diamond film wear behavior. On the other hand, MCD films are the most wear-resistant films due to their larger grains and lower B-doping levels. We propose a graphical scheme of the wear behavior which involves planarization and mechanochemically driven amorphization of the surface to describe the wear mechanism of B-doped diamond films. Finally, the wear behavior of the nucleation surface of NCD films is investigated for the first time. In particular, the nucleation surface is shown to be susceptible to higher wear compared to the growth surface due to its higher grain boundary line density.

In this work, we perform a first-principles study of graphene, nitrogen-, boron-doped graphene, and codoped graphene as the potential catalysts in nonaqueous lithium–oxygen (Li–O2) batteries. Among the samples studied, boron-doped graphene exhibits the lowest discharge and charge overpotentials, suggesting that boron-doped graphene is the best catalyst for both the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER) in nonaqueous Li–O2 batteries. Another significant finding is that codoping of nitrogen and boron atoms does not enhance the ORR/OER in the presence of lithium atoms, indicating that the synergistic effect in the presence of protons does not appear in nonaqueous Li–O2 batteries. This behavior is attributed to the fact that the existence of lithium atoms can change the most stable adsorption sites and adsorption energies of intermediates. Finally, on the basis of our calculation results, we propose that the adsorption energy of intermediates in the rate-determining step (RDS...

In this paper, boron doped activated wood derived carbon (BAWDC) was successfully employed to support and disperse polyaniline (PANI) particles for the application as supercapacitor electrode materials. Compared to pure PANI and BAWDC, the as-prepared polyaniline coated boron doped wood derived porous carbon composite (PANI–BAWDC) displays significantly enhanced specific capacitance, due to the synergetic effect between PANI and BAWDC. Moreover, the obtainable highest specific capacitance (421 F g–1 at 10 mV s–1, 372 F g–1 at 2 A g–1) and energy density (45.2 Wh kg–1 at 876 W kg–1) of this PANI–BAWDC composite are comparable to those of some similar PANI coated carbon composites, suggesting a good potential of PANI–BAWDC composite for future supercapacitor applications.

Tandem intramolecular electrophilic arene borylation was developed to facilitate access to B-doped polycyclic aromatic hydrocarbons (PAHs). DFT calculations revealed that electrophilic arene borylation occurred via a four-membered ring transition state, in which C-B and H-Br bonds formed in a concerted manner. An organic light-emitting diode employing the B-doped PAH as an emitter and a B-doped PAH-based field-effect transistor were successfully fabricated, demonstrating the potential of B-doped PAHs in materials science.

A systematic investigation of the boron-doped silicon clusters SinB with n ranging from 1 to 10 in the neutral, anionic, and cationic states is performed using quantum chemical calculations. Lowest-energy minima of the clusters considered are identified on the basis of the B3LYP, G4, and CCSD(T) energies. Total atomization energies and thermochemical properties such as ionization energy, electron affinity, and dissociation energies are obtained using the high accuracy G4 (B3LYP-MP4-CCSD(T)) and CCSD(T)/CBS (complete basis set up to n = 4) methods. Theoretical heats of formation are close to each other and used to assess the available experimental values. The growth mechanism for boron-doped silicon clusters SinB with n = 1–10 emerges as follows: (i) each SinB cluster is formed by adding one excess Si-atom into the smaller sized Sin–1B, rather than by adding B into Sin, (ii) a competition between the exposed (exohedral) and enclosed (endohedral) structures occurs at the size Si8B where both structures beco...

Electron transport properties of boron- and nitrogen-doped polycyclic aromatic hydrocarbons and cyclophanes are investigated with the nonequilibrium Green’s function method and compared to transpor...

Our first-principles calculations demonstrate that the substitutional B anion and B cation doped TiO2 both produce a spin magnetic moment of 1.0 μB despite their different mechanisms. The former is...

We report the results of density functional theory calculations on the electronic structure of boron-doped anatase TiO2. For the calculations we used both standard and hybrid exchange-correlation f...

Temperature dependence of the electric resistance was measured in the temperature range between 5 and 290 K for the assembly of the boron-doped multiwalled carbon nanotubes (B-doped MWNTs). The obs...

Statistical numbers of field-effect transistors (FETs) were fabricated from a circuit of 17-nm-wide, 34-nm-pitch Si nanowires boron doped at a level of 10(18) cm-3. Top-gated 4-microm-wide Si nanowire p-FETs yielded low off-currents (approximately 10(-12) A), high on/off ratios (10(5)-10(6)), good on current values (30 microA/microm), high mobilities (approximately 100 cm2/V-s), and low subthreshold swing values (approximately 80 mV/decade between 10(-12) and 10(-10) A increasing to 200 mV/decade between 10(-10)-10(-8) A).

We thank Mark Davis for assistance with NMR experiments and Mowafak Al-Jassim for facilitating EELS measurements. This work was funded by the U.S. Department of Energy Office of Energy Efficiency and Renewable Energy Hydrogen Program and by the Office of Science, Basic Energy Sciences, Division of Materials Sciences and Engineering under Subcontract DE-AC36-99GO10337 to NREL.

Explosive crystallization of SiGe alloys and boron-doped SiGe alloys is studied using a special molecular dynamics construction developed by the authors. For the case of Si1-xGex alloys, the simulations indicate that explosive crystallization should occur over the entire compositional range of Si1-xGex alloys at velocities high enough to prevent Ge segregation. The results show qualitative agreement with experimental results for Si-rich systems: Over a range of 0−25% germanium, the simulations predicted a nonlinear decrease in velocity that roughly matches the slope and extent of the rapid drop in interface velocity observed experimentally. An analogous investigation of boron-doped Si1-xGex alloys showed that the limit of incorporation of boron during explosive crystallization is strongly dependent on the amount of germanium present and that explosive crystallization is capable of limiting transient enhanced diffusion throughout the crystallization process.

The lithium absorption energies and electronic structures of the boron-doped single-walled carbon nanotubes (SWCNT) were investigated using the first-principles calculations. The lithium absorption energies in the B-doped SWCNTs are large negative values, compared with those in the pure SWCNT, whether Li is absorbed at inner sites or at outer sites of the tube walls. The B doping forms an electron-deficient structure in SWCNT, which can effectively accept the electrons from the absorbed Li and stabilize the Li absorption on the tube wall. The calculation results suggest that enhanced Li absorption capability in the B-doped SWCNT should be expected.

WITH A MASSIVE BLAST of boron, mild-mannered silicon, best known for its mediocre ability to conduct electricity, can be strong-armed into shuttling electrons virtually resistance-free ( Nature 2006, 444, 465). Scientists have been trying to get silicon to make this semiconductor-to-superconductor transformation for 60 years. Inciting a metamorphosis reminiscent of comic-book superheroes, a group led by Grenoble, France-based researchers Etienne Bustarret of the National Center for Scientific Research (CNRS) and Christophe Marcenat of the French Atomic Energy Commission (CEA) immersed a silicon film in BCl 3 gas and then blasted it with high-intensity laser light. With each blast, more and more boron was forced into the silicon until the boron concentration reached several percent. The researchers then cooled the film until they observed superconductivity just above absolute zero—at about 0.35 K. The extreme temperature "raises questions as to how useful this turncoat-silicon might be," notes Princeton Un...