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Alkaline zinc‐iron flow batteries (ZFBs) have recently attracted renewed attention. However, the critical issues with zinc anodes, such as dendrite formation, side reactions, and labile plating or stripping, have yet to be adequately addressed. Here, an attempt is made to overcome these challenges by designing Boron‐doped carbon‐felt (B–CF) electrodes rich in electron‐deficient sites and defects. The fabricated B–CF provides improved adsorption of negatively charged Zn(OH)42−, robust Zn nucleation sites, and lower Zn nucleation and deposition overpotentials, leading to homogeneous Zn deposition morphology. Uniform Zn deposition enables the prevention of undesirable dendrite growth and parasitic reactions. As a result, the constructed alkaline ZFBs achieve a high average Coulombic efficiency of ≈99.85% and energy efficiency of 88% with uniform Zn deposition during 300 cycles (40 mA cm−2). This work expands the understanding of the electrode design strategy for achieving favorable Zn plating/stripping. [ABSTRACT FROM AUTHOR]

The structural and luminescence properties of the Lu 3 Al 4 Sc 1 O 12 :Pr and Gd 3 Al 3 Sc 2 O 12 :Pr garnet scintillators co-doped with boron (B3+) ions were investigated. The addition of B3+ and Sc3+ to the structure has a positive effect on the luminescence properties, especially on the photo, radio emission intensities, quantum efficiency, and results in a reduction of the decay time, which is necessary for high-quality scintillators. Structural properties of garnets have been determined after X-ray diffraction analysis coupled with Rietveld refinement. Surface morphology analysis was performed using a scanning electron microscope and particle size was also determined. Elemental composition was confirmed by the ICP-OES technique. Reflection, excitation (in the UV and VUV range), emission (upon excitation by UV or X-rays), decay time, and quantum efficiency at room temperature were measured. Furthermore, the influence of temperature on excitation, emission, and decay curves was also analyzed. The obtained luminescence properties indicated positive effect caused by doping. [Display omitted] [ABSTRACT FROM AUTHOR]

Boron doping of biochar leads to the formation of activated oxygen species and pores and defects in the carbon structure Therefore, boron-containing biochar was prepared by treating boric acid (H3BO3) solutions in different concentrations of hazelnut shells before pyrolysis. DSC results showed that treatment of biomass with solutions containing a low concentration (0.1 wt. %) of H3BO3 increased the degradation of cellulose and hemicellulose, but also increased char formation. However, treatment with solutions containing 2% and 5% H3BO3 increased biochar oxidation with the formation of boron oxide (B2O3). The FT-IR and XPS results showed the presence of B–B, B–O, and B–O–B in the H3BO3 treatment, which is due to the formation of B2O3. The examination of the proliferation of L929 mouse fibroblast cells in response to different concentrations of boron-containing biochars using the MTT assay revealed that biochar treated with 2% H3BO3 promoted cell growth (100.32 ± 1.93). However, above this concentration, the formation of polycrystalline B2O3 species exhibited an inhibitory effect on cell proliferation (81.98 ± 1.26) in the samples of H3BO3-doped biochar with 5% concentration. The results of the in vitro hemolysis tests for undoped biochar and high boron-containing (% 5) biochar sample showed mild hemolytic activity, with percentages of 2.46 ± 0.02 and 3.08 ± 0.04, respectively, according to the reported standards. Antimicrobial studies have shown that Candida albicans (a yeast, ATCC 10231) is more sensitive to H3BO3 than Staphylococcus aureus (Gram-positive bacteria, ATCC 29213). Boron-containing biochar can be used in a variety of applications, including biosensing, drug delivery, biological scaffolds, and biological imaging, as well as an adsorbent in the removal of pollutants and a catalyst in oxidation and electrochemical reactions. [ABSTRACT FROM AUTHOR]

We have successfully fabricated a series of the SmCaBCuO bulk superconducting ceramics with different ratios of nanoscale Boron doping into mixture powder by the solid-state reaction method. Permanent magnets (PMs) with three different values in the same form were used for magnetic levitation force (MLF) measurements. During measurement of levitation forces between small PMs and bulk high Tc superconducting ceramic materials, significant hysteretic behavior was observed as a function of the distance between the magnet and the superconductor. We focused on the effect of doping and different permanent magnets on magnetic levitation force (MLF) measurements and magnetic stiffness calculations of materials, considering zero field-cooling (ZFC) and field-cooling (FC) conditions. It was seen that MLF decreased with the increase in boron dopant in the sample under ZFC conditions. We explained this result with weak bonds between grain boundaries, cracks and grain size reduction in the samples. Under FC conditions, with the increase of permanent magnet value and nano boron doping, the levitation force, which should be effective, left its place to the attractive force. Flux trapping centers formed by doping dominate the attractive force. The increase in doping caused a decrease in magnetic stiffness values. The increase in the permanent magnet caused an increase in the stiffness values of the material. This result agrees with the literature. The MLF and magnetic stiffness data got will be useful in the technological applications of maglev and carrier systems. [ABSTRACT FROM AUTHOR]

Abstract Boron-doped biochar (B-BC) was synthesized by pyrolysis using solid waste of sorghum straw as raw material. The specific surface area of B-BC increased significantly by 2.38 times compared to that of pure BC. This enhancement allowed B-BC (0.3 g L−1) to achieve complete adsorption of 10 mg L−1 tartrazine (TTZ) within 40 min. Moreover, acidic conditions were more favorable for TTZ adsorption, achieving complete removal of TTZ in only 15 min at a pH of 3.0. Interestingly, the adsorption rate of TTZ by B-BC in the presence of 0.05 M Cl− was approximately 2.12 times higher than that in the absence of Cl−. When other background electrolytes were present, excluding PO4 3−, complete adsorption of TTZ could also be achieved within 60 min. Thermodynamic analysis and DFT calculations described the parameters of B-BC for TTZ adsorption, including $$\Delta {\text{G}}^{\Theta }$$ Δ G Θ (

Boron-doped biochar (B-BC) was synthesized by pyrolysis using solid waste of sorghum straw as raw material. The specific surface area of B-BC increased significantly by 2.38 times compared to that of pure BC. This enhancement allowed B-BC (0.3 g L−1) to achieve complete adsorption of 10 mg L−1 tartrazine (TTZ) within 40 min. Moreover, acidic conditions were more favorable for TTZ adsorption, achieving complete removal of TTZ in only 15 min at a pH of 3.0. Interestingly, the adsorption rate of TTZ by B-BC in the presence of 0.05 M Cl− was approximately 2.12 times higher than that in the absence of Cl−. When other background electrolytes were present, excluding PO43−, complete adsorption of TTZ could also be achieved within 60 min. Thermodynamic analysis and DFT calculations described the parameters of B-BC for TTZ adsorption, including Δ G Θ (< 0 kJ mol−1), Δ H Θ (− 2.199 kJ mol−1), Δ S Θ (− 6.068 J mol−1 K−1), and the adsorption energy (Eads = − 0.6919 eV), indicating a tendency towards a spontaneous adsorption process. Moreover, the strong electron transfer ability of B-BC and the oxygen-containing groups promoted the activation of PDS and generation of active substances such as 1O2, O2•−, and SO4•−, thereby degrading TTZ into products with lower biological toxicity. When the added PDS was only 0.1 mM, the degradation rate constant of TTZ could reach 0.1481 min−1. Furthermore, boron doping enhanced the stability of biochar, enabling the complete removal of 10 mg L−1 TTZ even after recycling and regeneration. In summary, this study offers a practical solution for the resource utilization of solid waste sorghum straw and the treatment of TTZ-polluted wastewater. Highlights: Boron doping significantly increased the specific surface area of biochar by 2.38 times. B-BC exhibited complete adsorption of TTZ in only 15 min at a pH of 3.0. Addition of 0.05 M Cl− increased the adsorption rate of TTZ on B-BC by 1.12 times. Free radicals and nonradicals contributed to TTZ degradation in B-BC/PDS system. Degradation products of TTZ displayed reduced toxicity to typical aquatic organisms. [ABSTRACT FROM AUTHOR]

Diamond films possess numerous extraordinary physical and chemical properties, but their high-temperature applications are limited by its poor thermal stability. Herein, we fabricated the undoped microcrystalline diamond (MCD) film and heavy boron-doped diamond (h-BDD-1, 2.94 × 1021 atoms·cm−3; h-BDD-2, 9.10 × 1021 atoms·cm−3) films to investigate the effect of boron doping on the thermal stability of diamond films. A series of evidences, including air annealing experiments, thermogravimetric-differential scanning calorimetry (TG-DSC) analysis, and in-situ ultra-high-temperature confocal laser-scanning microscope (CLSM), demonstrated that the thermal stability of diamond films was obviously enhanced by boron doping. Consequently, the h-BDD-2 film exhibited the best thermal stability with an initial oxidation temperature above 900 °C, which was much higher than that of MCD film (709 °C). By deconvolving the X-ray photoelectron spectra, we believed that the transition of B–C bonds to stable oxy-boron carbide complexes (B 4 O–C, B 3 O–C) is the key to improving the thermal stability. These results not only reveal a new antioxidant mechanism of boron-doped diamond films but also pave a way for the application of diamond in high-temperature environments. [ABSTRACT FROM AUTHOR]

Single‐atom catalysts (SACs) have recently become highly attractive for selective hydrogenation reactions owing to their remarkably high selectivity. However, compared to their nanoparticle counterparts, atomically dispersed metal atoms in SACs often show inferior activity and are prone to aggregate under reaction conditions. Here, by theoretical calculations, we show that tuning the local electronic structures of metal anchor sites on g‐C3N4 by doping B atoms (BCN) with relatively lower electronegativity allows achieving zero‐valence Pd SACs with reinforced metal‐support orbital hybridizations for high stability and upshifted Pd 4d orbitals for high activity in H2 activation. The precise synthesis of Pd SACs on BCN supports with varied B contents substantiated the theoretical prediction. A zero‐valence Pd1/BCN SAC was achieved on a BCN support with a relatively low B content. It exhibited much higher stability in a H2 reducing environment, and more strikingly, a hydrogenation activity, approximately 10 and 34 times greater than those high‐valence Pd1/g‐C3N4 and Pd1/BCN with a high B content, respectively. [ABSTRACT FROM AUTHOR]

In the quest for effective photocatalysts for hydrogen production via photocatalytic water splitting, ZnIn 2 S 4 has garnered considerable attention due to its high photocatalytic hydrogen evolution capability. In this study, boron-doped ZnIn 2 S 4 was successfully synthesized via a hydrothermal method, with a small amount of cobalt phosphate (Co-Pi) decorated on its surface. The hydrogen evolution rate of boron-doped ZnIn 2 S 4 was determined to be 5.2 mmol g−1 h−1, surpassing that of pure ZnIn 2 S 4 by 1.68 times. Moreover, with the addition of Co-Pi to boron-doped ZnIn 2 S 4 , the hydrogen production rate escalated to 29.7 mmol g−1 h−1, which is 9.58 times higher compared to pure ZnIn 2 S 4. UV–vis analysis revealed that boron doping introduced new energy levels into ZnIn 2 S 4 , effectively narrowing the bandgap and enhancing light absorption wavelength range. Furthermore, PL and XPS analyses indicate that Co-Pi effectively captures photogenerated holes (h+) in ZnIn 2 S 4 , retaining photogenerated electrons and overcoming the disadvantage of electron-hole pair recombination in ZnIn 2 S 4. The doping and loading of Co-Pi as a cocatalyst ultimately contribute to enhancing hydrogen production efficiency, thereby significantly improving the photocatalytic hydrogen evolution capability of ZnIn 2 S 4. This study provides a scalable idea for designing composite catalysts in which doping and co-catalysts work together. • ZnIn 2 S 4 (ZIS) was synthesized hydrothermally using ZnCl 2 , In(NO 3) 3 ·xH 2 O, and thioacetamide (TAA) as precursors. • Defective ZnIn 2 S 4 (B-ZIS) was hydrothermally synthesized from ZIS and NaBH 4. • B-ZIS-CP composites were prepared through the in situ photodeposition of cobalt phosphide (Co-Pi) onto B-ZIS. • The composite catalysts exhibited exceptional photocatalytic activity for hydrogen evolution. • B-ZIS-CP demonstrates remarkable separation efficiency of photogenerated electron-hole pairs. [ABSTRACT FROM AUTHOR]

Among hydrogen production methods, water electrolysis stands out, but its efficiency is hampered by the substantial energy barrier of the oxygen evolution reaction (OER). To address this, incorporating electron‐deficient boron (B) into Co–Fe hydroxide (CoFeOxHy) promotes higher oxidation states of involved metals, greatly enhancing OER activity and charge transfer capabilities. Herein, the synthesis of a range of amorphous CoFeB nanoparticles with varying Fe to (Co+Fe) atomic ratios achieved through a simple chemical reduction method using CoFe‐Prussian blue analogs as precursors and employing Mössbauer spectroscopy to observe structural characteristics before and after transformation is reported. Among these nanoparticles, the CoFe0.25B variant, exhibiting favorable electrochemical properties, is chosen and subsequently subjected to hydrolysis to yield CoFe0.25BOH nanoparticles, serving as an active catalyst for OER. At a current density of 10 mA cm−2, the overpotentials for CoFe0.25OxHy and CoFe0.25BOH are 362 and 310 mV, respectively, with Tafel slopes decreasing from 393 to 93 mV dec−1. Furthermore, the i–t test reveals no significant loss of electrochemical performance within 24 h, substantiating the efficacy of enhancing the electrocatalytic performance of CoFeOxHy through the introduction of electron‐deficient elements. This research offers novel insights into the development of efficient and stable water electrolysis catalysts. [ABSTRACT FROM AUTHOR]

The increasing demand for safe and high-energy-density battery systems has led to intense research into solid electrolytes for rechargeable batteries. One of these solid electrolytes is the NASICON-type Li1+xAlxTi2−x(PO4)3 (LATP) material. In this study, different boron compounds (10% B2O3 doped, 10% H3BO3 doped, and 5% B2O3 + 5% H3BO3 doped) were doped at total 10 wt.% into the Ti4+ sites of an LATP solid electrolyte to investigate the structural properties and ionic conductivity of solid electrolytes using the solid-state synthesis method. Characterization of the synthesized samples was conducted using X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), and electrochemical impedance spectroscopy (EIS). The XRD patterns of the boron-doped LATP (LABTP) samples show that the samples have a rhombohedral phase with space group R 3 ¯ c together and low amounts of impurity phases. While all the LABTP samples exhibited similar ionic conductivity values of around 10−4 S cm−1, the LABTP2 sample doped with 10 wt.% H3BO3 demonstrated the highest ionic conductivity. These findings suggest that varying B3+ ion doping strategies in LATP can significantly advance the development of solid electrolytes for all-solid-state lithium-ion batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] Active site implantation and morphology manipulation are efficient protocols for boosting the electrochemical performance of carbon nitrides. As a promising sulfur host for lithium–sulfur batteries (LSBs), in this study, C 3 N 5 porous nanostructure incorporated with both boron (B) atoms and nitrogen (N) defects was constructed (denoted as ND–B–C 3 N 5) using a two-step strategy, i.e., pyrolysis of the mixture of 3-amino-1,2, 4-triazole and boric acid to obtain B-doped C 3 N 5 porous nanostructure and then KOH etching under hydrothermal condition to generate N defects. The doped B atoms in the C 3 N 5 porous nanostructure are in the form of B–N bonds and grafted B–O bonds. N defects are primarily created at the C N–C positions of the triazine unit, leaving behind some N vacancies and cyano groups. Benefiting from the involvement of B dopants and N defects, the optimized ND–B–C 3 N 5 –12 sample exhibits ameliorative conductivity, mass transport, lithium polysulfides (LiPSs) adsorption ability, diffusion of Li+ ions, Li 2 S deposition capacity, sulfur redox polarization, and a reversible solid–solid sulfur redox process. Consequently, the ND–B–C 3 N 5 –12/S cathode delivers accelerated redox performance of polysulfides for LSBs, revealing capacities of 1091 ± 44 and 753 ± 20 mAh/g at 0.2C for the initial and 300th cycles, respectively. The ND–B–C 3 N 5 –12/S cathode is also endowed with desired sulfur redox activity and stability at 2C for 1000 cycles, holding an initial discharging capacity of 788 ± 24 mAh/g and a low decay rate of 0.05 % per cycle. [ABSTRACT FROM AUTHOR]

It is important to achieve sustainable ammonia production under mild conditions, and the electrocatalytic nitrogen reduction reaction (NRR) is a promising strategy. However, the precise construction of highly active NRR electrocatalysts for ammonia synthesis remains challenging. Here, we construct B-doped PdRh mesoporous nanotubes (B-PdRh MNTs) as efficient NRR electrocatalysts. The mesoporous nanotubular structure provides abundant active sites, and B doping enhances the adsorption energy of N2. As such, the NH3 yield and Faraday efficiency of B-PdRh MNTs reach 12.03 μg h–1 mgcat–1 and 16.28% under 0.1 M Na2SO4, respectively. This work provides strategies for B-doped catalysts for efficient electrocatalytic NRR applications. [ABSTRACT FROM AUTHOR]

Formic acid has emerged as a highly promising hydrogen storage material, and the development of efficient catalysts to facilitate its dehydrogenation remains imperative. In this study, a novel catalyst consisting of palladium nanoparticles supported on boron-doped porous carbon (Pd/BPC) was successfully synthesized to enable efficient hydrogen production through the dehydrogenation of formic acid. The impacts of the boron doping ratio, doping temperature, and palladium reduction temperature on the catalyst's performance were systemically investigated. The results demonstrated the Pd/BPC catalyst synthesized with a carbon-to-boron ratio of 1:5 by calcination at 900 °C and subsequent reduction at 60 °C exhibited superior formic acid dehydrogenation performance, being 2.9 and 3.8 times greater than that of the Pd/PC catalysts without boron doping and commercial Pd/C, respectively. Additionally, the catalyst showed excellent cycle stability with no significant activity reduction after five consecutive cycles. Experimental and theoretical results reveal that boron doping not only facilitates the homogenous distribution of Pd nanoparticles but also induces a stronger support–metal interaction, thereby reinforcing the catalytic performance. This research is expected to provide valuable insights into the economically viable and efficient production of environmentally friendly hydrogen energy. [ABSTRACT FROM AUTHOR]

This study aims to improve the structural strength of the commonly used Ti-15Zr alloy in dental applications by investigating the effects of low boron additions. Ti-15Zr alloys containing 1-4% boron have been produced by vacuum arc melting. The phase ratios in the microstructure of the produced alloys vary according to the boron content. With increasing boron content, the ratio of TiB compound in the phase structure increases. The hardness of Ti-Zr-B alloys exhibited a notable increase in correlation with rising boron content. Measured hardness values of 36.31, 39.50, 44.14, and 53.40 displayed a clear upward trend with higher boron percentages. The tensile strength of the Ti-Zr-B alloys exhibits a trend of initially increasing with boron content, reaching its highest value of 888 MPa at 1% boron. The yield strength follows a similar with tensile strengh, with an initial rise from 449 MPa at 0% boron to a peak of 562 MPa at 1% boron content. Beyond this point, the yield strength slightly decreases to 469 MPa at 2% boron but sharply drops to 186 MPa at 4% boron content. As boron content increases in the Ti-Zr-B alloys, the percentage elongation, indicating the material's plastic deformation capacity before fracture, consistently decreases from 17.03% at 0% boron to 0.70% at 4% boron content. [ABSTRACT FROM AUTHOR]

High specific capacity and long cycle life are the key to high-performance lithium–sulfur (Li–S) batteries, but they are hard to achieve simultaneously due to the notorious polysulfide shuttle effect. Transition metal oxide nanocatalysts are expected to help address the above issue, but their low conductivity and cumbersome synthesis process limit their application. Here, we propose a defect engineering strategy to induce electron rearrangement by heteroatom doping. Boron-doped spinel-type oxide (B-ZnCo2O4‑x) is synthesized by a two-step hydrothermal method for separator modification. The boron-produced oxygen vacancy (OV) increases unsaturated sites by changing the electron cloud density, and therefore, the B-ZnCo2O4‑x nanocatalyst can reduce the reaction energy barrier and accelerate the nucleation and activation rate of Li2S. Meanwhile, the unique pore defects effectively increase the Li+ flux and ensure battery performance at a high rate and high sulfur loading. The battery equipped with a B-ZnCo2O4‑x-modified separator delivered an initial specific capacity of 1108 mAh g–1 at 0.2 C and a capacity retention rate of 80.4% at 0.5 C after 200 cycles. In particular, at a high sulfur loading of 10.0 mg cm–2, the battery yielded a first-cycle capacity of 1321.9 mAh g–1. This work demonstrates that boron-doping-enabled defect engineering is an effective strategy to improve the catalytic activity of transition metal oxides for application in Li–S batteries. [ABSTRACT FROM AUTHOR]

Sub band gap states play a crucial role in device performance. Intrinsic and p-type hydrogenated amorphous silicon are used in solar cell but they have significantly different sub band gap states. So an intrinsic (i-aSiO:H) and delta doped (δ p-aSiO:H, 0.01% gas phase doping) hydrogenated amorphous silicon oxide were investigated. These two layers have very similar optical band gap but different conductivities and mid-gap states. The Urbach energy and midgap defect states of the i-aSiO:H and δ p-aSiO:H materials were 103, 151 meV and 8.19 × 10 16 , 5.47 × 10 17 cm - 3 respectively. In the δ p-a-SiO:H a reduction in optical gap from 1.99 to 1.967 eV and a shift in Fermi level by 0.258 eV was observed. But because of low level of doping the δ p-a-SiO:H layer resulted in a moderate power conversion efficiency (PCE of 8.66%) when it was used as p-type layer in amorphous solar cell simulation. In a HIT-type device simulation, Λ -type variable optical gap i-aSiO:H passivation layer shows PCE of 26.4%. [ABSTRACT FROM AUTHOR]

Porous carbon materials have increasingly drawn interest for applications ranging from supercapacitive energy storage to bioengineering. However, a simple and scalable fabrication process of such materials, employing low‐cost chemical compounds without sacrificing morphological and chemical control, remains lacking. Here, a novel, rapid, continuous bottom‐up strategy for synthesizing structurally tunable porous carbon network films on insulating and conductive substrates is reported. By employing rapid thermal annealing (RTA) of a commercial polyacrylonitrile‐based blend, simultaneous phase separation and thermal crosslinking are induced, effectively freezing the structure. Subsequent burning of degradable components generates a porous carbon framework (d¯pore${\bar{d}}_{{\mathrm{pore}}}$ ≈ 360 to 700 nm) doped with nitrogen and oxygen atoms. Introducing a boron‐containing reagent in the precursor solution enables boron doping and pore size reduction as small as 20 nm, enhancing materials' performance. The direct fabrication of micro‐supercapacitors on stainless steel substrates is demonstrated, achieving an areal capacitance of 12.7 mF cm−2 at 50 mV s−1, with ≈98% retention after 10 000 charge/discharge cycles. The benefit of boron doping is further highlighted for wound healing applications. Because RTA is already an established industrial method, this platform directly facilitates the synthesis of functional porous heteroatom‐doped carbon structures using commercial polymers and dopants for various applications. [ABSTRACT FROM AUTHOR]

Photo-electrocatalysis is a growing field, and cobalt-based metal-organic frameworks (Co-MOFs) are attracting much interest because of their porous nature, high surface area, and malleable structure. This study investigated the photo-electrocatalytic properties of g-C 3 N 4 and boron-doped-g-C 3 N 4 when hybridized with cobalt-based MOF (ZIF-67). In this work, we describe the preparation of novel g-C 3 N 4 /ZIF-67 and B-g-C 3 N 4 /ZIF-67 composites by poly-condensation and co-condensation methods, respectively. ZIF-67 hybridization caused a decrease in the band gap energy of g-C 3 N 4 due to changes in the crystalline structure and size. EIS results indicated that only B-g-C 3 N 4 /ZIF-67 showed a response to light irradiation. At the same time, both B-g-C 3 N 4 /ZIF-67 and g-C 3 N 4 /ZIF-67 demonstrated sufficient light response when the potential applied was increased to -1.2 V vs. NHE in LSV analyses. CO 2 reduction to ethanol was performed for 3 hours at -1 V vs. NHE under continuous light irradiation and CO 2 bubbling for each catalyst. Ethanol production rates were recorded as 10.024, 12.0168, 30.7230, and 32.1096 μmol/cm2.h for g-C 3 N 4 , B-g-C 3 N 4 , g-C 3 N 4 /ZIF-67, and B-g-C 3 N 4 /ZIF-67, respectively. [Display omitted] • ZIF-67 was uniformly distributed in the B-g-C 3 N 4 /ZIF-67 composite, while it grew only on the surface of g-C 3 N 4 /ZIF-67. • Boron doping was strongly influencing the electric activity of the catalyst. • ZIF-67 slightly increased the electric conductivity and strongly influenced the light response. • The B-g-C 3 N 4 /ZIF-67 composite exhibited a remarkable 206.5% increase in ethanol production rate compared to g-C 3 N 4. [ABSTRACT FROM AUTHOR]

Constructing a stable solid electrolyte interphase (SEI) at the electrode–electrolyte interface is powerful for optimizing the battery performance. However, studies related to interface chemistry have particularly focused on engineering electrolytes and overlooked regulating electrode materials. Here, this study reports that the B‐doped Bi interconnected nanoparticles (B─Bi) are prepared by a facile and effective chemical reduction reaction. The B doping helps to catalyze the electrolyte decomposition and more NaF formation on the electrode surface, which facilitates a stable uniform SEI with enhanced mechanical stability. Such a robust SEI layer can inhibit the further decomposition of electrolytes and promote the interfacial Na+ transfer. The B─Bi offers a reversible capacity of 403.1 mAh g−1 at 1.0 A g−1 and a high rate capability of 203 mAh g−1 at 80 A g−1. Moreover, the B‐doping method also finds its viability to stabilize SEI in Sb material. This study demonstrates a new strategy for engineering the interface chemistry toward stable SEI and excellent performance. [ABSTRACT FROM AUTHOR]

[Display omitted] Designing two-dimensional (2D) porous carbon nanosheets is a promising strategy for enhancing the water-splitting activities of non-noble metal catalysts. In this study, we developed a novel method for synthesizing the novel three-dimensional (3D) hierarchically porous iron–nickel (FeNi) nanoparticles encapsulated in boron (B) and nitrogen (N)-codoped porous carbon nanosheets (denoted as FeNi@BNPCNS). Owing to the advantages of morphology and structure of B and N, 10.31 atom % of B/N active centers were successfully doped into the optimal FeNi@BNPCNS-800 nanosheets. FeNi@BNPCNS-800 exhibited better hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) electrocatalytic activities than control catalysts in an alkaline solution. However, the HER and OER electrocatalytic activities of FeNi@BNPCNS-800 were slightly lower than 20 wt% Pt/C and RuO 2. The FeNi@BNPCNS-800||FeNi@BNPCNS-800 electrolyzer achieved 10 mA cm−2 at 1.514 V, which was 73 mV lower than that of 20 wt% Pt/C||RuO 2 electrolyzer (1.587 V). The perfect 3D honeycomb-like architectures, abundant mesopores/defects, and abundant electrocatalytic active sites were attributed to the outstanding water-splitting performances of FeNi@BNPCNS-800 nanosheets. This study provides an efficient strategy for the large-scale, rapid, and low-cost fabrication of 2D porous carbon nanosheets without using any template, surfactant, or expensive raw material, thus presenting a simple approach to design advanced non-noble metal electrocatalysts for water splitting. [ABSTRACT FROM AUTHOR]

Electrical properties of pseudo‐vertical Schottky barrier diodes (pVSBDs) prepared on (113)–oriented boron‐doped diamond (BDD) layers using ruthenium (Ru) for both the ohmic and Schottky contacts are investigated. First, Ru ohmic contacts are evaporated on homoepitaxial BDD layers with different resistivity, and their specific contact resistance is measured using circular transfer length method structures after annealing at various temperatures up to 750 °C. Then, pVSBD structures are fabricated on the boron‐doped bilayer consisting of a lower, heavily boron‐doped layer ensuring an ohmic contact and an upper, lightly doped layer providing a rectifying Schottky contact. After necessary mesa etching, both contacts are formed by the Ru evaporation. The results show that Ru forms a stable ohmic contact with very low contact resistance (10−5–10−6 Ω cm2) when deposited on BDD layers with metallic conductivity. It also provides an acceptable Schottky contact on low‐doped (113) homoepitaxial BDD. Both contacts, which are made simultaneously, realize pVSBDs with low on‐state resistance and low forward voltage drop. However, the lower barrier of the ruthenium contacts results in higher leakage. Ru pVSBDs thus show a lower rectification ratio, higher leakage, and a worse ideality factor compared to analogical pVSBDs using molybdenum contacts. [ABSTRACT FROM AUTHOR]

Heteroatom‐doped peri‐acenes (PAs) have recently attracted considerable attention considering their fascinating physical properties and chemical stability. However, the precise sole addition of boron atoms along the zigzag edges of PAs remains challenging, primarily due to the limited synthetic approach. Herein, we present a novel one‐pot modular synthetic strategy toward unprecedented boron‐doped PAs (B‐PAs), including B‐[4,2]PA (1 a‐2), B‐[4,3]PA (1 b‐2) and B‐[7,2]PA (1 c‐3) derivatives, through efficient intramolecular electrophilic borylation. Their chemical structures are unequivocally confirmed with a combination of mass spectrometry, NMR, and single‐crystal X‐ray diffraction analysis. Notably, 1 b‐2 exhibits an almost planar geometry, whereas 1 a‐2 displays a distinctive bowl‐like distortion. Furthermore, the optoelectronic properties of this series of B‐PAs are thoroughly investigated by UV/Vis absorption and fluorescence spectroscopy combined with DFT calculation. Compared with their parent all‐carbon analogs, the obtained B‐PAs exhibit high stability, wide energy gaps, and high photoluminescence quantum yields of up to 84 %. This study reveals the exceptional ability of boron doping to finely tune the physicochemical properties of PAs, showcasing their potential applications in optoelectronics. [ABSTRACT FROM AUTHOR]

The design of pseudocapacitive electrodes that exhibit high‐rate and high volumetric capacitances is a big challenge, since it requires subtle modulation of ion‐intercalation structures that are able to achieve high electrochemical activity, fast ion transport, and facilitated electron transfer, simultaneously. Herein, controllable and selective etching of B atoms from B‐doped Ti3AlC2 precursors is reported, which generates boron‐vacancy doped MXene (B‐V‐MXene) nanosheets with finely‐regulated, ion‐intercalation structures. Electrochemical studies and density‐functional‐theory calculations demonstrate that Ti around vacancies possess higher surface‐redox activity with protons than those on pristine MXenes for the improvement of capacitances. In addition, interlayer spacing can be optimized on B‐V‐MXenes in promoting proton intercalation. More importantly, the dopant B atoms can increase the electron density on Ti, facilitating the adsorption of the intercalated protons; and further, B 2p‐Ti 3d hybridized band sits closer to the Fermi energy than that of C 2p bands, which bridges the energy gap for electron transfer in the pseudo‐capacitive reaction. With synergy of all these effects, the novel B‐V‐MXene compact electrodes can deliver the previously unmatched high volumetric capacitances of 807 F cm−3 at 1,000 mV s−1 and 1,815 F cm−3 at 5 mV s−1, with excellent cycle stability over 10,000 cycles. [ABSTRACT FROM AUTHOR]

In this paper, nitrogen-doped, boron-doped and boron and nitrogen co-doped activated carbon supported nickel–copper was used as catalyst for ethanol gas-phase carbonylation reaction. The yield of propionic acid and ethyl propionate was improved greatly by boron and nitrogen co-doping. BET, XRD, XPS, TEM, and CO-TPD were used to study the effects of nitrogen and boron doping on catalytic performance. Nitrogen doping and boron doping improve the dispersion of metal on the surface of activated carbon. Aiming at the problem of low stability of nickel-based catalyst, the regeneration method of the catalyst was explored. The results show that the activity of the catalyst can be recovered by H2 treatment at 400 ℃. According to the results of the catalyst regeneration experiment and the characterization of the catalyst before and after the reaction and regeneration, the cause for the deactivation of the catalyst were discussed. The results show that the formation of NiI2 is the main cause of catalyst deactivation. [ABSTRACT FROM AUTHOR]

CoCrFeNi high-entropy alloy (HEA) exhibits excellent mechanical properties but relatively poor wear resistance. In particular, when the load reaches a certain level and the deformation mechanism of the CoCrFeNi HEA changes, the formation of shear bands leads to a significant increase in wear rate. Although numerous studies have been conducted on alloying strategies to improve the wear resistance of alloys, there is still limited research on the influence of deformation mechanism adjustment on wear resistance. Therefore, in order to fill this research gap, this study aims to use boron doping to regulate the deformation mechanism and successfully improve the wear resistance of CoCrFeNi HEA by 35 times. By observing the subsurface microstructure, the mechanism behind the significant improvement in wear resistance was further revealed. The results indicate that the reduction of shear bands and the formation of nanostructured mixed layers significantly improve wear resistance. The proposed strategy of boron doping to change the deformation mechanism and improve wear resistance is expected to provide new enlightenment for the development of wear-resistant HEAs. [ABSTRACT FROM AUTHOR]

The enhancement of the fluorination degree of carbon fluorides (CFx) compounds is the most effective method to improve the energy densities of Li/CFx batteries because the specific capacity of CFx is proportional to the molar ratio of F to C atoms (F/C). In this study, B‐doped graphene (BG) is prepared by using boric acid as the doping source and then the prepared BG is utilized as the starting material for the preparation of CFx. The B‐doping enhances the F/C ratio of CFx without hindering the electrochemical activity of the C–F bond. During the fluorination process, B‐containing functional groups are removed from the graphene lattice. This facilitates the formation of a defect‐rich graphene matrix, which not only enhances the F/C ratio due to abundant perfluorinated groups at the defective edges but also serves as the active site for extra Li+ storage. The prepared CFx exhibits the maximum specific capacity of 1204 mAh g−1, which is 39.2% higher than that of CFx obtained directly from graphene oxide (without B‐doping). An unprecedented energy density of 2974 Wh kg−1 is achieved for the as‐prepared CFx samples, which is significantly higher than the theoretically calculated energy density of commercially available fluorinated graphite (2180 Wh kg−1). Therefore, this study demonstrates a great potential of B‐doping to realize the ultrahigh energy density of CFx cathodes for practical applications. [ABSTRACT FROM AUTHOR]

In spite of the widespread range of hydrogen applications as one of the greenest energy vectors, its transportation and storage still remain among the main concerns to be solved in order to definitively kickstart a rapid takeoff of a sustainable H2 economy. The quest for a simple, efficient, and highly reversible release storage technique is a very compelling target. Many studies have been undertaken to increase H2 storage efficiency by exploiting either chemisorption or physisorption processes, or through entrapment on different porous solid materials as sorbent systems. Among these, biomass-derived carbons represent a category of robust, efficient, and low-cost materials. One question that is still open-ended concerns the correlation of H2 uptake with the kind and number of heteroatoms as dopant of the carbonaceous sorbent matrix, such as boron, aiming to increase whenever possible bonding interactions with H2. Furthermore, the preferred choice is a function of the type of hydrogen use, which may involve a short- or long-term storage option. In this article, after a brief overview of the main hydrogen storage methods currently in use, all the currently available techniques for the boronation of activated carbonaceous matrices derived from recycled biomass or agricultural waste are discussed, highlighting the advantages and drawbacks of each of them.

Sulfur poisoning is a major challenge in catalytic processes where it can result in a gradual decline in the activity of the metal catalyst or a complete deactivation of the catalyst. Many studies were conducted to investigate the effects of sulfur poisoning on metals and address this challenge by developing a catalyst that is resistant to sulfur poisoning without compromising its performance. Boron doping showed to be a promising approach to modify the properties of metal catalysts and improve their performance in various applications. In this work, periodic density functional theory (DFT) calculations were conducted to study boron doping on a number of metals and its impact on sulfur poisoning. The DFT calculations show that boron doping impacts metals differently. Boron doping is favourable on few metals (Pd, Pt, Rh and Ru) and very unfavourable on other metals (e. g. Ag and Cu). On Pd, Pt and Rh, boron doping has a positive impact on reducing sulfur poisoning, with the impact varying with boron concentration. Finally, as a case study, the impact of boron doping on H2S splitting to create H2 was examined and boron doping was shown to have a positive impact on the performance of Pd‐based catalyst. [ABSTRACT FROM AUTHOR]

Formic acid has emerged as a highly promising hydrogen storage material, and the development of efficient catalysts to facilitate its dehydrogenation remains imperative. In this study, a novel catalyst consisting of palladium nanoparticles supported on boron-doped porous carbon (Pd/BPC) was successfully synthesized to enable efficient hydrogen production through the dehydrogenation of formic acid. The impacts of the boron doping ratio, doping temperature, and palladium reduction temperature on the catalyst’s performance were systemically investigated. The results demonstrated the Pd/BPC catalyst synthesized with a carbon-to-boron ratio of 1:5 by calcination at 900 °C and subsequent reduction at 60 °C exhibited superior formic acid dehydrogenation performance, being 2.9 and 3.8 times greater than that of the Pd/PC catalysts without boron doping and commercial Pd/C, respectively. Additionally, the catalyst showed excellent cycle stability with no significant activity reduction after five consecutive cycles. Experimental and theoretical results reveal that boron doping not only facilitates the homogenous distribution of Pd nanoparticles but also induces a stronger support–metal interaction, thereby reinforcing the catalytic performance. This research is expected to provide valuable insights into the economically viable and efficient production of environmentally friendly hydrogen energy.

Here, we find that B-doped TiO2-x prepared via a one-pot method exhibit excellent performance on adsorption and photodegradation of various dyes. The B-doping extends the light absorption edge to 520 nm and its major role is the adsorption of organic dyes, while Ti3+-doping is responsible for the light response at 500–800 nm and > 800 nm and contributes more for the dye degradation. >15 dyes were investigated and high adsorption efficiency was achieved for cationic dyes without -COOH/-SO3H groups. Besides electrostatic adsorption, direct bonding of = N+(CH3)2 with B/B-O sites play an important role in enhancing the adsorption capability.

As a significant parameter in tuning the structure and performance of the boron-doped diamond (BDD), the thickness was focused on the mediation of the boron doping level and electrochemical properties. BDD films with different thicknesses were deposited on silicon wafers by the hot filament chemical vapor deposition (HFCVD) method. The surface morphology and composition of the BDD films were characterized by SEM and Raman, respectively. It was found that an increase in the BDD film thickness resulted in larger grain size, a reduced grain boundary, and a higher boron doping level. The electrochemical performance of the electrode equipped with the BDD film was characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) in potassium ferricyanide. The results revealed that the thicker films exhibited a smaller peak potential difference, a lower charge transfer resistance, and a higher electron transfer rate. It was believed that the BDD film thickness-driven improvements of boron doping and electrochemical properties were mainly due to the columnar growth mode of CVD polycrystalline diamond film, which led to larger grain size and a lower grain boundary density with increasing film thickness. [ABSTRACT FROM AUTHOR]

In spite of the widespread range of hydrogen applications as one of the greenest energy vectors, its transportation and storage still remain among the main concerns to be solved in order to definitively kickstart a rapid takeoff of a sustainable H2 economy. The quest for a simple, efficient, and highly reversible release storage technique is a very compelling target. Many studies have been undertaken to increase H2 storage efficiency by exploiting either chemisorption or physisorption processes, or through entrapment on different porous solid materials as sorbent systems. Among these, biomass-derived carbons represent a category of robust, efficient, and low-cost materials. One question that is still open-ended concerns the correlation of H2 uptake with the kind and number of heteroatoms as dopant of the carbonaceous sorbent matrix, such as boron, aiming to increase whenever possible bonding interactions with H2. Furthermore, the preferred choice is a function of the type of hydrogen use, which may involve a short- or long-term storage option. In this article, after a brief overview of the main hydrogen storage methods currently in use, all the currently available techniques for the boronation of activated carbonaceous matrices derived from recycled biomass or agricultural waste are discussed, highlighting the advantages and drawbacks of each of them. [ABSTRACT FROM AUTHOR]

Fabrication of ordered structures at the nanoscale limit poses a cornerstone challenge for modern technologies. In this work we show how naturally occurring moiré patterns in Ir(111)-supported graphene template the formation of 2D ordered arrays of substitutional boron species. A complementary experimental and theoretical approach provides a comprehensive description of the boron species distribution, bonding configurations, interfacial interaction with Ir(111) and the impact on graphene's electronic structure. Atomically-resolved scanning tunnelling microscopy images and density functional theory calculations reveal that boron preferably forms small aggregates of substitutional defects in geometrically low regions of the moiré superlattice of graphene, by inducing local bending of graphene towards the underlying Ir(111). Surprisingly, calculations reveal that the incorporation of electron deficient boron does not lead to an enhanced p-type doping, as the local rippling of the graphene layer prompts electron uptake from the iridium substrate that compensates the initial electron loss due to substitutional boron. Scanning tunnelling spectroscopy and angle-resolved photoemission spectroscopy measurements corroborate that the arrays of boron species do not modify the electronic structure of graphene near the Fermi level, hence preserving the slight p-type doping induced by Ir(111). [Display omitted] [ABSTRACT FROM AUTHOR]

Lead dioxide-based electrodes have shown a great performance in the electrochemical treatment of organic wastewater. In the present study, modified PbO2 anodes supported on stainless steel (SS) with a titanium oxide interlayer such as SS/TiO2/PbO2 and SS/TiO2/PbO2-10% Boron (B) were prepared by the sol–gel spin-coating technique. The morphological and structural properties of the prepared electrodes were characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and X-ray photoelectron spectroscopy (XPS). It was found that the SS/TiO2/PbO2-10% B anode led to a rougher active surface, larger specific surface area, and therefore stronger ability to generate powerful oxidizing agents. The electrochemical impedance spectroscopy (EIS) measurements showed that the modified PbO2 anodes displayed a lower charge transfer resistance Rct. The influence of the introduction of a TiO2 intermediate layer and the boron doping of a PbO2 active surface layer on the electrochemical degradation of ampicillin (AMP) antibiotic have been investigated by chemical oxygen demand measurements and HPLC analysis. Although HPLC analysis showed that the degradation process of AMP with SS/PbO2 was slightly faster than the modified PbO2 anodes, the results revealed that SS/TiO2/PbO2-10%B was the most efficient and economical anode toward the pollutant degradation due to its physico-chemical properties. At the end of the electrolysis, the chemical oxygen demand (COD), the average current efficiency (ACE) and the energy consumption (EC) reached, respectively, 69.23%, 60.30% and 0.056 kWh (g COD)−1, making SS/TiO2/PbO2-10%B a promising anode for the degradation of ampicillin antibiotic in aqueous solutions. [ABSTRACT FROM AUTHOR]

Structurally precision graphene nanoribbons (GNRs) have attracted great interest considering their prospective applications as organic carbon materials for nanoelectronics. The electronic properties of GNRs not only critically depend on the edge structure and width but also on the heteroatom type, doping position, and concentration. Motivated by the recent undisputable progress in the synthesis of stable boron‐doped polycyclic aromatic hydrocarbons (B‐PAHs), considerable efforts have been devoted to the precision synthesis of the corresponding boron‐doped GNRs (B‐GNRs) via bottom‐up synthesis approach in recent years in view of the extraordinary ability of boron doping on modulating their physiochemical properties. In this review, an overview of the bottom‐up organic synthesis of B‐GNRs, including the precursor design and synthesis, structure characterization of the resulting B‐GNRs, and investigation of their electronic properties is provided. Moreover, the future challenges and perspectives regarding the bottom‐up synthesis of B‐GNRs are also discussed. The authors hope that this review will further stimulate the synthesis and device integrations of B‐GNRs with a combined effort from different disciplines. [ABSTRACT FROM AUTHOR]

This paper discusses the challenges relative to the silicon thinning which allows the back side power delivery integration (BSPDN). The back side silicon thinning stopping on a thin Si 0.75 Ge 0.25 etch stop layer (ESL) has been investigated as it represents an alternative to the use of SOI wafers. Etch stop layers using 10 nm Si 0.75 Ge 0.25 or 10 nm Si 0.75 Ge 0.25 boron doped (Si 0.75 Ge 0.25 :B) have been studied for which different thinning process sequences were considered. All the considered thinning sequences are terminated with a diluted ammonia (NH 4 OH) process which provides the selectivity towards the ESL. Considering a 10 nm Si 0.75 Ge 0.25 :B as an ESL considerably increases the selectivity of the last diluted NH 4 OH silicon etching step. It nevertheless induces a risk of device poisoning caused by the diffusion of boron. Considering a 10 nm Si 0.75 Ge 0.25 as an ESL has been then demonstrated using different thinning process sequences. Those alternative thinning sequences were optimized with respect to the silicon removal within wafer uniformity. • Back side Si thinning using SiGe ESL as an alternative to SOI. • Initial enablement of a BS Si thinning with 50 nm SiGe Si 0.75 Ge 0.25 as an ESL. • Si thinning stopping on boron doped Si 0.75 Ge 0.25 which increases the selectivity of the of the alkaline Si wet removal. • New thinning sequences developed to enable the BS thinning on SiGe Si 0.75 Ge 0.25 as an ESL. [ABSTRACT FROM AUTHOR]

Modulating the generation pathway of reactive species is an appealing approach for improving the photocatalytic performance of polymerized carbon nitride (PCN). In this study, boron-doped tubular PCN with carbon defects (BCNT) was synthesized via thermal polymerization. It was confirmed that boron dopants with adjacent carbon defects were introduced into the heptazine ring of carbon nitride, which redistributed the localized electron density and strengthened the adsorption of O 2. The generation of long-lived reactive species, e.g., •O 2 − and 1O 2 , was thus enhanced markedly, whereas the generation of short-lived radicals, e.g., •OH, was decreased. Additionally, the electron-deficient boron dopants and neighboring carbon defects synergistically reduced the Gibbs free energy of H 2 O 2 formation, thereby promoting its participation in photocatalytic reactions. Although •O 2 − was the main reactive species, 1O 2 and H 2 O 2 also played considerable roles. Consequently, the photocatalytic degradation of sulfadiazine by BCNT was significantly enhanced (by 6.39 times) compared to that by PCN. [Display omitted] • B-doped tubular PCN with C defects was designed to produce long-lived active species. • The dipole moment of BCNT was enlarged to promote the separation of charge carriers. • Local electron density of BCNT was redistributed, thus enhancing the O 2 adsorption. • B doping modulated the conversion pathway of •O 2 − and fortified the H 2 O 2 production. • Photocatalytic degradation of SDZ over BCNT was 7.39 times as fast as that over PCN. [ABSTRACT FROM AUTHOR]

[Display omitted] • H[B]MCM-22 with variable Al distribution in the framework is synthesized. • The highly dispersed Mo nanoparticles are obtained in boron modified Mo/H[B]MCM-22 (SBR 30) catalyst. • The acid strength distribution and Brønsted/Lewis acid ratio are precisely tuned by boron introducing. • Mo/H[B]MCM-22 (SBR 30) exhibits high yield to aromatics of 7 % after 10 h. • The coke deposition of Mo/H[B]MCM-22 (SBR 30) decreases by 16% compared with Mo/H[B]MCM-22 (SBR 5). Mo/HMCM-22 is one of the candidate catalysts for methane dehydroaromatization (MDA) reaction. However, serious coke deposition would deactivate the catalyst, resulting in a rapid decrease of aromatics yield. Here, we adjusted the acidity of MCM-22 zeolite by doping boron into the framework. Boron species replace some of framework aluminum and prompt aluminum to locate in sinusoidal channel. It optimizes the ratio of strong/weak Brønsted acid, as well as enhances the interaction between molybdenum and HMCM-22 to facilitate the dispersion of molybdenum species. After 10 h of MDA reaction, the yield of aromatics over Mo/H[B]MCM-22 (SBR 30) is 3.5 times higher than that of Mo/H[B]MCM-22 (SBR 5). It decreases by only 4.8 % in comparison to the initial yield. Meanwhile, Mo/H[B]MCM-22 (SBR 30) shows significantly better resistance to coke deposition. Therefore, the established structure–activity relationships provide valuable insights for future research on the modification of zeolite acidity in methane dehydroaromatization reaction. [ABSTRACT FROM AUTHOR]

Nitric oxide (NO) pollutant can threaten the regional environment and human health. Solar-powered photocatalytic oxidation method is desirable for NO removal (ppb level) at ambient conditions, but suffers from the unsatisfactory activity and poor selectivity due to the sluggish molecular oxygen activation. Herein, we demonstrate that efficient photocatalytic NO removal can be realized by modulating the defects distribution of amorphous TiO 2 via boron doping. Theoretical calculations and experimental results reveal that H 3 BO 3 modification can refine the structure of surface oxygen vacancies, promoting electron-rich molecular oxygen activation to •OH. Meanwhile, bulk-phase oxygen defects can be filled by free-state B atoms, accelerating the electron transfer via Ti-O-B bonding. Homogeneous boron-doped amorphous TiO 2 achieves about 5 times higher NO removal efficiency (∼50%) than that of amorphous TiO 2 (∼9%) without releasing remarkable NO 2 (selectivity, ∼97%). This study provides a state-of-the-art approach for robust photocatalytic NO removal by engineering the defect distribution. [Display omitted] • The homogeneous boron-doped amorphous TiO 2 was prepared by solvothermal method. • Boron doping can regulate the oxygen defect distribution of amorphous TiO 2. • Boron doping facilitated the molecular oxygen activation to •OH. • Photocatalytic NO removal was enhanced by the cooperation of boron doping and oxygen vacancy. [ABSTRACT FROM AUTHOR]

We investigate the electronic and vibrational properties of bottom-up synthesized aligned armchair graphene nanoribbons of N = 7 carbon atoms width periodically doped by substitutional boron atoms (B-7AGNRs). Using angle-resolved photoemission spectroscopy and density functional theory calculations, we find that the dopant-derived valence and conduction band states are notably hybridized with electronic states of Au substrate and spread in energy. The interaction with the substrate leaves the bands with pure carbon character rather unperturbed. This results in an identical effective mass of ≈0.2 m0 for the next-highest valence band compared with pristine 7AGNRs. We probe the phonons of B-7AGNRs by ultrahigh-vacuum (UHV) Raman spectroscopy and reveal the existence of characteristic splitting and red shifts in Raman modes due to the presence of substitutional boron atoms. Comparing the Raman spectra for three visible lasers (red, green, and blue), we find that interaction with gold suppresses the Raman signal from B-7AGNRs and the energy of the green laser (2.33 eV) is closer to the resonant E22 transition. The hybridized electronic structure of the B-7AGNR-Au interface is expected to improve electrical characteristics of contacts between graphene nanoribbon and Au. The Raman fingerprint allows the easy identification of B-7AGNRs, which is particularly useful for device fabrication.

A new type of metal-free catalyst was successfully prepared by doping boron (B) in the carbon nanotube. The catalyst had 99.4% removal of phenol in 60 min at pH 7 by activating peroxymonosulfate (PMS). In order to explore the origin of the high catalytic activity, the samples were characterized by Raman and electron paramagnetic resonance (EPR), and the reactive oxygen species (ROS) in the process of catalytic degradation were investigated. The Raman results showed that the defect sites increased after doping, which indicated that the B doping increases the active sites on the surface of the carbon nanotubes. Identification experiments of ROS found that not only hydroxyl radicals (·OH) and sulfate radical (S O 4 − ∙) , but also singlet oxygen (1O2) exist in the system. The presence of multiple free radicals indicated the existence of free radical reaction pathway, and the presence of 1O2 confirmed the existence of non-radical reaction pathway. These results indicated that there were dual reaction pathways for the activation of persulfate by B-doped carbon nanotubes, which was the intrinsic nature for the high catalytic activity of the system. [ABSTRACT FROM AUTHOR]

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The boron-assisted catalytic graphitization of carbonaceous materials is an attractive methodology for enhancing their electrical properties by modulating the chemical structures of pristine carbons. In this study, polyacrylonitrile-based carbon fibers (CFs) with highly developed microstructures were prepared by boron-assisted catalytic graphitization. Hydrothermally immersed CFs in boric acid were heat-treated up to 2700 °C, and their chemical structures were traced to investigate the boron-assisted catalytic graphitization mechanism. Boron from the gasified boron-related functional groups of CFs diffused into the CFs to form boron carbide, B 4 C. The boron-substituted CFs exhibited a highly developed crystalline structure that could not be achieved by heat treatment alone, indicating that boron accelerated the graphitic carbon structure. As a result, boron-assisted catalytic graphitization at 2700 °C simultaneously enhanced the electrical and thermal conductivities of CFs, with values of 3677.8 S/cm and 365.9 W/mK, respectively, which were 2.8 and 2.4 times higher than those of heat-treated CFs at 2700 °C. In addition, CFs were used to prepare CF papers using a wet-laid process, and their heat generation and thermal management capabilities were evaluated. Considering affordable CFs compared to nanomaterials, we believe that our study provides a feasible approach for fabricating heating elements and heat sinks. [Display omitted] [ABSTRACT FROM AUTHOR]

The exceptional biocompatibility of Zn-based single-atom nanozymes (SAzymes) has led to extensive research in their application for disease diagnosis and treatment. However, the fully occupied 3d 10 electron configuration has seriously hampered the enzymatic-like activity of Zn-based SAzymes. Herein, a B-doped Zn-based SAzymes is fabricated by carbonizing zeolite-like Zn-based boron imidazolate framework at different temperatures (Zn-SAs@BNC x , x = 800, 900, 1000, and 1100 °C). The formed B─N bond yielded a local electric field, which changes the position of the d-band center and improved the oxidation state of Zn by facilitating the electron transfer from Zn to N to B. These changes enhanced the adsorption and activation of H 2 O 2 and O 2 by Zn-SAs@BNC 1000 , increasing the nanozymes' multi-enzyme catalytic activity. B doping led to 24.81-, 32.37-, and 13.98-fold increase in the peroxidase-, oxidase- and catalase-like, respectively, catalytic efficiency (K cat /K m ) of Zn-SAs@BNC 1000 when compared with no B doping. In addition, Zn-SAs@BNC 1000 showed excellent ability to kill tumor cells both in vitro and in vivo. This study demonstrates that the modulation of the electron configuration of Zn is an effective strategy to develop efficient anti-tumor approaches by boosting the enzymatic activity of Zn-based SAzymes., (© 2024 Wiley‐VCH GmbH.)

CoCrFeNi high-entropy alloy (HEA) exhibits excellent mechanical properties but relatively poor wear resistance. In particular, when the load reaches a certain level and the deformation mechanism of the CoCrFeNi HEA changes, the formation of shear bands leads to a significant increase in wear rate. Although numerous studies have been conducted on alloying strategies to improve the wear resistance of alloys, there is still limited research on the influence of deformation mechanism adjustment on wear resistance. Therefore, in order to fill this research gap, this study aims to use boron doping to regulate the deformation mechanism and successfully improve the wear resistance of CoCrFeNi HEA by 35 times. By observing the subsurface microstructure, the mechanism behind the significant improvement in wear resistance was further revealed. The results indicate that the reduction of shear bands and the formation of nanostructured mixed layers significantly improve wear resistance. The proposed strategy of boron doping to change the deformation mechanism and improve wear resistance is expected to provide new enlightenment for the development of wear-resistant HEAs.