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Elemental doping is considered to be a promising approach for altering the electronic structure, optical absorbance, and charge separation characteristics of graphitic carbon nitride (g‐C3N4, termed as CN), thus boosting its photocatalytic performance for practical applications. Herein, a series of boron (B) doped g‐C3N4 (named as BCN) photocatalysts are developed via one‐step pyrolysis of a mixture of urea and 3‐methoxycarbonyl‐5‐nitriophenylboronic acid (MCNPBA). The results show that B‐atoms have been successfully incorporated into the g‐C3N4 network. The as‐synthesized BCN‐x (x shows the weight content of MCNPBA) photocatalysts are evaluated in photocatalytic hydrogen (H2) evolution from water splitting under visible‐light (λ ≥ 420 nm). The optimized BCN‐10 sample shows a maximum H2 evolution rate of 1789.93 µmol h─1 g─1, which is 6.2 times higher than that of g‐C3N4 (289.73 µmol h─1 g─1). This is attributed to the fact that the electron‐deficient B‐atoms are lewis acids that trap electrons, which in turn expands visible‐light absorption, narrows the bandgap, and prevents the recombination of photogenerated charge carriers. Moreover, B‐doping can readily modify the valence and conduction band positions of g‐C3N4, therefore augmenting the photocatalytic H2 evolution activity. This paper presents a unique rational framework for developing other functionalized electron‐deficient elemental‐doping g‐C3N4‐based photocatalysts for practical applications in solar‐to‐fuel conversion. [ABSTRACT FROM AUTHOR]

Worldwide, the harmful ion contamination of water has become a serious problem because of unregulated industry, energy production, and mining, which greatly increase the concentration of pollutants in water. The novel membranes through adsorbent self-assembly, such as protein amyloids, were explored for wastewater treatment. Herein, we report amyloid fibril (AF)-embedded bacterial cellulose nanohybrid membrane for efficient removal of heavy metal from industrial effluent. AFs are synthesized by heat treatment using bovine serum albumin and embedded with bacterial cellulose nanomembrane (BCN). The AF-embedded BCN (AF/BCN) was characterized using microscopy and spectroscopic methods. In addition, the well-ordered multi-layered AF/BCN filtration assembly was fabricated in the commercial cartridge and validated for the removal of heavy metals (Pb2+ and Hg2+) from wastewater and treatment of industrial wastewater sample containing heavy metals. Our multi-layered filtration assembly removed Hg2+ and Pb2+ with efficiency of 95 and 78.34%, respectively. A computational study using molecular docking has also been performed for the identification of metal entrapment sites. Moreover, our AF/BCN filtration assembly showed high regeneration capacity up to four cycles. The isotherm model also revealed a strong fit and good adsorption behaviour. This makes potential filtration assembly for low-cost, high-efficiency for the removal of heavy metal from wastewater. HIGHLIGHTS Computational approaches methods for the study of bovine serum albumin.; Synthesis of amyloid fibril, amyloid-embedded bacterial cellulose nanomembrane (BCN), and fabrication of amyloid-embedded BCN filtration assembly.; Heavy metal removal analysis from industrial wastewater.;

Germanium-based nanomaterials have gained prominence as potential enhancers of energy harvesting efficiency and storage capacity, attributed to their superior electrical conductivity, mobility, and lithium-ion storage aptitude. However, their practical application is often hindered by chemical and physical instabilities. In this study, we introduce a facile synthesis method for boron-carbon-nitride (BCN) shell-coated germanium nanowires (Ge@BCN NWs), designed to shield the Ge core from environmental factors while augmenting its electrical conductivity. Through microscopic and spectroscopic analyses, we confirmed the Ge core is completely encapsulated by a highly crystalline BCN shell. Electron transport measurements on the Ge@BCN NWs field-effect transistor (FET) revealed minimal hysteresis alongside heightened electrical conductivity, suggesting that the BCN shell acts as an efficacious protective barrier, curtailing the degradation of Ge NWs. Our approach presents a reliable method for bolstering the stability of nanomaterials and achieving functional 2D coated NWs. [ABSTRACT FROM AUTHOR]

In this study, we examined the molecular structure of pristine and defective BCN surfaces for the adsorption of lithium polysulfides. We introduced C/B/N vacancies to the 2D BCN surface and observed that the bandgap decreased in the order of BCN > C–BCN > B–BCN > N–BCN. The adsorption of lithium polysulfides on both pristine and defective BCN surfaces was primarily through physisorption. Our results indicated that the N–BCN surface showed good adsorption with smaller lithium polysulfides, while the C–BCN surface bound strongly with longer lithium polysulfides. We found that introducing vacancies in BCN surfaces improved the adsorption of lithium polysulfides, with values comparable to those of other 2D materials. Therefore, we propose that defective BCN surfaces can be effectively utilized as a cathode scaffold for lithium polysulfide capture in lithium–sulfur batteries. [ABSTRACT FROM AUTHOR]

[Display omitted] • Metal-free BCN electrocatalysts with Lewis acid-base pairs have been prepared. • BCN exhibit high catalyst activity and durability in the electrocatalytic NRR process. • DFT calculations investigate the mechanism of performance enhancement in NRR. • 15N 2 Isotope experiments confirm the origin of N atoms in NH 3. The electrocatalytic nitrogen reduction reaction (NRR) for ammonia (NH 3) under ambient conditions is emerging as a potentially sustainable alternative to the traditional, energy-intensive Haber-Bosch process for ammonia production. Currently, metal-based electrocatalysts constitute the majority of reported NRR catalysts. However, they often suffer from the shortcomings of competitive reactions of nitrogen adsorption/activation and hydrogen generation. Therefore, there is an urgent need to develop more environmentally friendly, low energy consumption, and non-polluting high-performance metal-free electrocatalysts. In this study, borocarbonitride (BCN) materials derived from boron imidazolate framework (BIF-20) were used to boost efficient electrochemical nitrogen conversion to ammonia under ambient conditions. The BCN catalyst demonstrated excellent performance in 0.1 M KOH, with an ammonia yield of 21.62 μg h−1 mg cat -1 and a Faradaic efficiency of 9.88% at −0.3 V (Reversible Hydrogen Electrode, RHE). This performance is superior to most metal-free catalysts and even some metal catalysts for NRR. The 15N 2 /14N 2 isotope labeling experiments and density functional theory (DFT) calculations showed that N 2 can be adsorbed and converted to NH 3 on the surface of BCN, and that the energy barrier can be significantly reduced by structural design for BCN. This work highlights the important role played by the presence of Lewis acid-base pairs in metal-free catalysts for enhancing electrochemical NRR performance. [ABSTRACT FROM AUTHOR]

Traditional method for preparing boron carbon nitride (BCN) usually involves solvents in the pretreatment process before pyrolysis at high temperature. Here, we report that highly porous BCN with controllable 3D morphology can be synthesized successfully by rapid solvent-free ball milling followed by pyrolysis processes using B 2 O 3 , dicyandiamide (DCD) and polyvinylpyrrolidone (PVP) as the sources of B, N and C, respectively. It is found that the porosity of the synthesized BCN varies from the amount of carbon source and the maximum specific surface area of 1386.7 m2g-1 with pore volume of 1.13 cm3g-1 can be achieved. The as-synthesized porous BCN materials exhibit excellent sorption capacities for methyl blue (MB), Congo red (CR) and basic yellow-1 (BY) up to 1220, 865.2 and 560 mgg−1, respectively. Such outstanding adsorption performance is mainly due to the high porosity with polar surface of the BCN. Furthermore, the BCN can be easily regenerated by combustion in air at 400 °C and used repeatedly. [Display omitted] [ABSTRACT FROM AUTHOR]

This work evaluated the influence of titanium carbo-nitride (TiCN), chromium aluminum nitride (CrAlN), and boron carbo-nitride (BCN) coatings deposited on AISI 1045 steel and their behavior in fatigue life. Suitable deposition parameters were established to obtain appropriate deposition times for polycrystalline growth and desired stoichiometry, as well as a stable layer thickness of ~ 3 μm. The physical and chemical properties of the obtained coatings were established by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and nanoindentation. Scanning electron microscopy (SEM) was used for analyzing the fracture surfaces of the samples subjected to fatigue. The analysis of the fatigue behavior of the uncoated and coated substrates was performed under rotary bending conditions applying maximum alternating stresses in the interval of 55 to 70% of the ultimate strength value, i.e., from 479 to 610 MPa, respectively. The test was conducted at room temperature. It was established that the fatigue resistance properties increased for the three types of coated samples, TiCN, BCN, and CrAlN, with values of 9.6%, 4.2%, and 3.9%, respectively, calculated for 1 × 106 cycles. The highest value in fatigue life improvement corresponded to the TiCN coating. This is associated with the increase in the mechanical properties of the coating, as well as the lower presence of tensile type stresses. The mechanical and fatigue results found in these ternary coatings deposited on AISI 1045 steel open up the possibility of future applications in mechanical devices, e.g., automotive applications with high fatigue demands in service conditions. [ABSTRACT FROM AUTHOR]

در این پژوهش حذف آلاینده‌های آلی از آب تولید شده از مخزن گازی پس از جداسازی مواد روغنی مورد بررسی قرار گرفته است، به‌نحوی‌که بتوان COD آن را از مقداری حدود mg/L 9500 به محدوده مجاز آب کشاورزی رساند. در ابتدا با توجه به اینکه هدایت الکتریکی پساب خیلی بالا و در حد µS/cm 6300 است از روش تبخیر جهت کاهش آن استفاده شد که طی این فرآیند هدایت الکتریکی و COD آن به‌ترتیب به µS/cm 1100 و mg/L 750 تقلیل پیدا کرد. با توجه به رسیدن COD پساب به کم‌تر از mg/L 1000 در ادامه از روش فتوالکتروکاتالیست برای تصفیه محصول حاصل از فرآیند تبخیر استفاده شد. در روش فتوالکتروکاتالیست از نانومواد نیمه‌ هادی بور کربن نیترید (BCN) به‌عنوان فتوکاتالیست در میکروراکتور نوع سیم پیچی با نسبت سطح به حجم بالا در حدود 3 m2/m 3000 استفاده شد که همین امر باعث اکسیداسیون سریع مواد آلی می‌شود. پس از ساختن میکروراکتور، تأثیر پارامترهای مختلف بر میزان حذف COD مورد بررسی قرار گرفت که مشخص شد بیشترین میزان حذف COD در 3=pH، اختلاف پتانسیل V 20 و هدایت الکتریکی µS/cm 2500 به‌دست می‌آید (80%) که طی آن COD به mg/L 150 کاهش یافته که مناسب برای آبیاری و کشاورزی است.

The graphene based materials in water pollutant treatment have recently gained significant attention due to their high surface area, high mechanical strength and tuneable surface chemistry. However, the relatively high cost, poor hydrophobicity, low adsorption capacity, and recyclability limit their practical application. Here in, driven by need, we report a simple approach for the synthesis of graphene quantum dots (GQDs) via pyrolysis, preferred because of high controllability and fewer defects over chemical exfoliation methods. The synthesized GQDs are further embedded on bacterial cellulose nanopaper (BCN) and characterized using spectroscopy and microscopy techniques. Furthermore, the well-ordered multi-layered GQD embedded BCN based filtration assembly is designed and developed for treatment of water pollutants and industrial dye wastewater. The multi-layered GQD embedded BCN based filtration assembly is validated by purifying industrial dye and heavy metal (Hg2+, Pb2+) with removal efficiency of 99.6% and 97%, respectively. Our multi-layered filtration assembly demonstrated significant membrane regeneration capacity until six cycles. The isotherm model also showed an appropriate fit exhibiting good adsorption behaviour. Our multi-layered filtration assembly can be established as a promising filtration assembly for inexpensive, efficient and low energy applications in wastewater treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • Adsorption of F 2 and O 3 gas on BCN and G_BN nanosheet has been studied via DFT calculation. • Both sheets show strong adsorbent-gas interaction with minimal recovery times. • Significant band gap decrement is observed due to gas adsorption. In the industry era, nanostructures-based gas sensors have been more striking for environmental monitoring. In this research, we investigated the properties and the adsorption ability of boron carbon nitride (BCN) and in-plane graphene-boron nitride (G_BN) nanosheets for toxic (F 2 and O 3) gas molecules. The geometrical, electronic, and optical properties of the selected structures are analyzed using the density functional theory. The negative value of cohesive energy signifies that both BCN and G_BN are energetically stable. Both structures show strong attractive energy for the selected gas molecules with recovery times of 0.266 ps−5.482 ns. A significant change decrease in the band gap of the adsorbents occurred after gas adsorption. All the adsorbents show a high absorption coefficient of over 104 cm−1 in the visible wavelength range. A slight variation in the optical properties is observed after gas adsorption. Both the adsorbents demonstrate significant sensitivity toward F 2 and O 3 gases. [ABSTRACT FROM AUTHOR]

BCN materials with varied structures are attracting attention for promising diverse applications. BCN materials are recognized for adaptable electrical properties, outstanding mechanical behavior, exceptional chemical inertness, and high thermal stability, which make them advantageous for corresponding applications in harsh environments. In this article, we thoroughly summarize BCN material theory, growth, properties, and applications. Properties of BCN thin films depend on the composition and growth technique, which facilitates in developing BCN films prevailing between insulating BN and semimetallic graphite. Regarding this, the effects of synthesis parameters on various BCN properties are examined. Dry and wet etching, which are imperative for device processing, are explored. Prompted by the success of graphene, graphene-analogous BCN nanomaterials are being researched intensively due to their unique chemical and physical properties. This article highlights BCN nanomaterials, their synthesis in different dimensions, and properties with prospective applications. We focus on their energy applications in supercapacitors, batteries, oxygen and hydrogen evolution reaction, water purification, and CO2 adsorption along with other biosensing applications. Performance of BCN nanomaterials is discussed and compared with the prevailing benchmark materials to present an evolutionary perspective of BCN nanomaterial progress. Finally, unresolved issues are highlighted, and future development opportunities are identified.

High performance, all solid-state planar micro-supercapacitor (MSC) with interdigitated Boron carbon Nitride (BCN) electrodes are fabricated via fast, scalable laser patterning technique. Heteroatom doping desirably enhances the electrochemical activity of carbon electrodes. This BCN based micro-supercapacitor showed comparatively very high specific capacitance of 72 mFcm−2 at a current density of 0.15 mAcm−2. Even at a high current density of 1 mAcm−2 device showed specific capacitance as high as 17 mFcm−2. It has demonstrated excellent electrochemical stability when tested up to 80000 cycles without any sign of further decay in capacity/efficiency. This device showed stable capacity even after bending at 150° angle, for 1500 times during cycling showing remarkable flexibility. Image 1 [ABSTRACT FROM AUTHOR]

Based on density functional calculations, tight-binding models are proposed for few layers of three BCN allotropes sandwiched between two layers of graphene. The results pave the road toward investigation of the performance of novel nanoelectronic devices such as vertical tunneling field effect transistors and nanoscale sensors operating on the basis of quantum tunneling through these layered materials-based systems. [ABSTRACT FROM AUTHOR]

A significant enhancement of photocatalytic H 2 evolution performance was realized over the BCN-TiO 2 (A+R) heterojunctions. The synergistic effect of heterojunction and phase-junction increases carrier lifetime and photocatalytic activity due to the formation of intimate interfacial structure and large contact area. • BCN-TiO2(A+R) heterojunctions was constructed via a calcination method. • Intimate interfacial structure with large contact area was obtained. • BCN-TiO2(A+R) exhibited the highest photocatalytic activity of H 2 evolution. • Synergistic effect of heterojunction and phase-junction increases carrier lifetime. In this work, BCN-TiO 2 (A+R) heterojunctions were constructed via a simple one-step calcination method as efficient photocatalysts for H 2 evolution. Simultaneously, an anatase/rutile phase-junction was also obtained due to the crystalline phase transformation that occurred during high-temperature calcination. The unique heterojunction and phase-junction lead to the formation of an intimate interface and large contact area between two semiconductors and extended the visible-light absorption range. Therefore, BCN-TiO 2 (A+R) heterojunctions with a mixed anatase and rutile phase exhibit enhanced photocarrier separation efficiency, realizing an eleven-fold increase in the electron lifetime compared to that of pure TiO 2 and yielding a remarkable visible-light-driven H 2 evolution rate nearly 7.5 and 12.2 times higher than that of TiO 2 (A+R) and pure BCN, respectively. This work provides a new strategy for designing efficient water-splitting photocatalysts with highly efficient charge separation and transfer. [ABSTRACT FROM AUTHOR]

Honeycomb architectures of h-BN/rGO nano-hybrids were built from the self-assemblies of hexagonal boron nitride (h-BN) and graphene oxide (GO) through microwave heating for a few seconds. Incorporation of h-BN nanosheets into 3D reduced graphene oxide (rGO) foams was accompanied by the removal of oxygen-containing groups during the rapid "bread baking" process. TEM and SEM images revealed the layer-stacked structure of the samples. XPS, Raman and XRD spectra showed the presence of h-BN layers that were interlaced into the honeycomb architectures of rGO frameworks. The microwave absorption properties and the complex permittivity could be adjusted by varying the microstructure and the content of h-BN. For the wax composite filled with 6.25 wt% h-BN/rGO nano-hybrid with thickness of 1.8 mm, the reflection loss value reached −35.63 dB at 17.2 GHz, and the effective frequency bandwidth reached 6.96 GHz at 2.6 mm with a low surface density. The honeycomb architecture of the hybrid provided multiple electromagnetic transmission paths and consumed significant amount of microwave energy due to the multiple interfaces. Embedding h-BN in the architecture enables excellent impedance matching, and provides highly efficient dielectric material that can be used for microwave absorption. This work demonstrates that microwave treatment is a facile approach to obtaining optimal microwave absorbing properties of h-BN/rGO nano-hybrids. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Carbon doped boron nitride (BCN) could serve as an efficient solid base catalyst. • It shows a high activity for Knoevenagel condensation of benzaldehyde with malononitrile. • The reaction follows a dissociative adsorption mechanism on oxygen terminated BCN edges. • C atoms doping plays a vital role in promoting the desorption of the intermediates. Abstract Development of new heterogeneous base catalysts for Knoevenagel condensation reactions is critical for practical applications. Herein, we demonstrate that carbon doped hexagonal boron nitride (BCN) exhibits a high catalytic activity for Knoevenagel condensation of benzaldehyde with malononitrile, producing benzylidene malononitrile under mild reaction conditions. An 81.9% conversion can be achieved over BCN after 15 min reaction time, which is 1.8 times with respect to hexagonal boron nitride (h -BN) and 27 times over C 3 N 4. Moreover, the BCN catalyst could be easily separated and recycled for several runs without obvious deactivation. Experimental results, spectroscopic characterizations, combined with first-principle calculations, suggest the reaction likely follows a dissociative adsorption mechanism on the oxygen terminated BCN edge. The C atoms doping plays a vital role in promoting the desorption of the intermediates. This study can open up a new avenue for the Knoevenagel condensation reaction with metal-free catalysis. [ABSTRACT FROM AUTHOR]

Photocatalytic conversion of CO2 to usable fuel precursors is one of the most important renewable paths to mitigate energy shortages and greenhouse gas emissions. Photocatalysts for this transformation are typically based on precious metals to obtain high yield and selectivity. Currently, metal‐free graphitic conjugated materials (such as g‐C3N4, ternary boron carbon nitride) are promising and emerging photocatalysts to offset the above issues. Here we further modulated photocatalytic performance of ternary boron carbon nitride (BCN) by introducing fluorine into its graphitic‐like framework. As a result, the fluorination of the BCN productively increases the CO yield by three times under visible light. It was found that fluorine doping can remarkably accelerate migration‐separation efficiency of photogenerated charge carriers, prolong lifetime of the excited state and optimize electronic properties of BCN. Be a boron! Boron carbon nitride ternary (BCN) is promising and emerging metal‐free visible light‐driven conjugated photocatalysts. Here, fluorine‐doped BCN (BCN−F) was rationally designed and applied in photocatalytic CO2 conversion in MeCN/H2O/TEOA system under visible light. The as‐obtained BCN−F photocatalysts exhibited enhanced CO2‐to‐CO conversion activity and high stability due to optimized electronic properties, accelerated charge transfer‐separation efficiency and prolonged lifetime of the excited state. [ABSTRACT FROM AUTHOR]

Abstract Boron and nitrogen co-doped carbon (BCN) seems to exhibit excellent electrochemical properties very suitable as electrode material for supercapacitor applications. On the other hand, MoS 2 possessing sheet-like structure proves to be favorable for electrolytic ion intercalation. Here in composites resulting from hydrothermally integrated MoS 2 flakes with the BCN have been studied to determine its potency as electrode material for supercapacitor application. Owed to the high packing density of layered MoS 2 flakes the as-prepared BCN/MoS 2 composite exhibits high volumetric capacitance corresponding to a value of 798 F cm−3 together with the enhanced gravimetric capacitance of 283 F g−1 at the current density of 1 A g−1. Electrochemical studies reveal improved coulombic efficiency, energy, and power densities for the as-prepared BCN/MoS 2 composite owed to the established synergy and the presence of interfaces involving two different materials. These results clearly show the usefulness of integration BCN and MoS 2 flakes resulting in BCN/MoS 2 hybrid as an apt electrode material for supercapacitor application. Graphical abstract Image 1 Highlights • Composite with integrated BCN and MoS 2 shows augmented capacitive properties. • BCN/MoS 2 composite shows excellent volumetric capacitance due to high density. • Created interlayer interfaces enhance coulombic efficiency and cyclic stability. • The energy and power density for the BCN/MoS 2 composite also undergo a boost. [ABSTRACT FROM AUTHOR]

This study addresses two algorithms for set stabilisation of Boolean control networks (BCNs). Based on the semi‐tensor product tool, the dynamics of BCNs can be characterised by its labelled digraph, which derived an graphical expression for the set stabilisation of BCNs. Then, two tree‐search algorithms, namely, generalised breadth‐first search and generalised depth‐first search, are proposed for the first time to decide the controllers for the set stabilisation of BCNs. In addition, some properties concerning the tree search algorithm are proposed. Finally, an example is employed to show the application of the presented algorithms. [ABSTRACT FROM AUTHOR]

Utilizing 2D layered materials as one of the composite's members in the synthesis of active material for supercapacitors is acquiring imperative attention on account of the extraordinary outcomes due to their wholesome hale structural and electrochemical affinity. Here, by rousing from intralayer ostwald ripening impelled growth of in situ spawned 1D Nb 2 C rods on 2D Nb 2 C sheets, in short form (h)Nb 2 C are generated via hydrothermal low temperature treatment without, which overwhelms the electrochemical performance of pure 2D MXene sheets. Later the residue less direct pyrolysis method was adopted for the in-situ development of 2D BCN nanosheets over MXene, 1D-2D/2D MXene/BCN hybrid nanoarchitectonics. The process method enabled the interrelated structural growth of BCN particles on MXene and helps in empowering the pseudocapacitive activity of the enlarged portion of Nb sites by the removal of the terminal groups. Thus, the fabricated 1D-2D/2D Nb 2 C/BCN (NBCN) electrode showed a specific capacitance of 765 F g − 1 at 2 A g − 1 current density with a high specific energy of 35 Wh kg−1. Eventually, the solid-state supercapacitor device further withstands 100,000 cycles displaying high efficiency and ∼100% retention. Henceforth, the 1D-2D/2D heterostructures with magnificent electrochemical properties can act as a feasible energy storage system. TOC [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Highly soluble boron carbon nitride as a new compound for BNCT, a targeted radiotherapy for cancer cells. • Synthesized material is relatively less toxic and could be used for biomedical applications. • BCN demonstrates stronger anti-tumorimpact on HeLa and U-87MG cell lines than L-BPA, aclinically tested compound. Boron Neutron Capture Therapy (BNCT) is a targeted radiotherapy modality in which 10B enriched compounds are delivered for local treatment of the cancer cells. In this work, boron carbon nitride (BCN) has been explored as a potential boron compound for BNCT. BCN compound with high solubility has been synthesized by simple solvothermal method. Structural analysis show synthesis of hexagonal BCN with presence of defect states. Morphological analysis show formation of layered structure with highly porous network. The optical properties have also been studied and calculated band gap of material is ∼3.85 eV. Cytotoxicity analysis show that synthesized material is relatively less toxic and can be explored for BNCT applications. The anti-tumor effect on HeLa and U-87MG cell lines show potential of BCN in comparison to clinically studied L-BPA compound. [ABSTRACT FROM AUTHOR]

Many efforts have been devoted to the reduction of atmospheric CO 2 and the development of a route map for sustainability in the energy and environmental sectors. The present work describes the bandgap tailoring of the ternary metal sulfide ZnIn 2 S 4 (ZIS) with two-dimensional (2D) boroncarbonitride (BCN) and a constructed heterostructure. The ratio of BCN to ZIS has been varied in different ratios and examined for morphological, structural, and optical characterization. The crystalline structure of the synthesized materials was subjected to Materials Studio software, which examined the geometry, stacking, and interaction between ZIS and layered BCN. ZIS/BCN-1 is found to be efficient compared to all other counter catalysts under study. Diffuse reflectance infrared Fourier transform (DRIFT) and Gas Chromatography Mass spectrophotometry (GC-MS) analysis confirm the formation of carbon monoxide and methane gas. In the presence of ZIS/BCN-1, it was found to produce 158 and 57 μmol g−1h−1 of CO and CH 4 , respectively, during CO 2 reduction under visible light. The effect of sacrificial agents has been investigated, and found that triethanolamine (TEOA) showed enhanced activity compared to others. The mechanism of photocatalysis has been discussed in detail and found to form type-II heterostructure through the interface between ZIS and BCN. The stability of ZIS/BCN-1 is good even after 5 cycles of the CO 2 reduction experiment, and no structural changes were found. [Display omitted] • Ratio of BCN is optimized to obtain efficient ZIS/BCN heterostructure. • Enhanced photocatalytic reduction of CO 2 is observed in ZIS/BCN-1 heterostructure. • ZIS/BCN-1 showed ability to produce 158 and 57 μmol g−1h−1 of CO and CH 4 , respectively. • DRIFT IR and GC-MS analysis confirms the formation of CO and CH 4. • Photocatalytic mechanism has been discussed in detail and follows type-II heterojunction. [ABSTRACT FROM AUTHOR]

Exploiting highly efficient and stable photocatalysts for Cr(VI) reduction is of great importance. Herein, both homojunction and heterojunction are introduced into a novel QDs self-decorated Bi 2 MoO 6 coupled with two-dimensional BCN (BCN-BMO(Q)) photocatalyst to achieve an enhanced performance of Cr(VI) reduction. Owing to the unique structure of the ternary system, electron-hole pairs are efficiently separated and transfer from the Bi 2 MoO 6 QDs to Bi 2 MoO 6 to BCN under visible-light excitation. Interestingly, 5% BCN-BMO(Q) shows stable and optimal performance for Cr(VI) photo-reduction activity within 20 min, which is almost 7.14, 2.28 and 1.66 times higher than that of BCN, BMO and BMO(Q) respectively under visible light irradiation. This work provides an alternative route to improve the photocatalytic activity of Bi 2 MoO 6 -based or some other nanocomposites. [ABSTRACT FROM AUTHOR]

This paper investigates the disturbance decoupling problem for Boolean control networks. Firstly, using the matrix semi‐tensor product, the logical dynamic equations of Boolean control networks are converted into discrete time linear equations. Secondly, the solvability of the disturbance decoupling problem is analyzed based on the structure matrices of BCNs, and a method for design state‐feedback controllers is put forward to deal with this problem. Two necessary and sufficient conditions for the disturbance decoupling problem of BCNs are obtained. Then an algorithm is provided to design controllers for calculating the disturbance decoupling forms of Boolean control networks. Finally, an illustrative example is given to describe the proposed algorithm. [ABSTRACT FROM AUTHOR]

BCN-TiO 2 nanocomposites are obtained by a simple calcination method using a hexagonal boron carbon nitride (BCN) semiconductor and nanotubular titanic acid (NTA) as precursors. The BCN-TiO 2 nanocomposites are characterized systematically by XRD, TEM, XPS, DRS, ESR, BET, I-t and PL techniques. Compared with the novel TiO 2 or single BCN sample, the BCN-TiO 2 nanocomposites prepared by a calcination method show the highest photocatalytic activity for hydrogen production under visible-light irradiation. The photocatalytic activity of BCN-TiO 2 nanocomposites is optimized by changing the amount of BCN. Characterization results confirm that a large amount of single electron oxygen vacancies can be formed when NTA was calcined at the higher temperature, which is beneficial to the enhancement of visible light absorption and the transfer of photogenerated carriers due to the formation of ohmic contact at the interface between BCN and novel TiO 2 . Therefore, the visible light photocatalytic activity for H 2 production of BCN-TiO 2 nanocomposites has been improved significantly by the formation of BCN-TiO 2 Z-scheme photocatalyst, which results in efficient space separation of photo-induced charge carriers. [ABSTRACT FROM AUTHOR]

This study addresses the output regulation problem of Boolean control networks (BCNs) in the presence of exogenous disturbances, which are characterised by two‐valued mutually independent random logical variables. By using the semi‐tensor product technique, the BCNs with stochastic perturbations are represented in their compact algebraic forms, and then a relating augmented system is constructed, which facilitates the analysis of the output regulation problem for the BCNs. As a consequence, necessary and sufficiency criteria are obtained to ensure the existence of the state feedback controllers which efficaciously solve the considered problem. Moreover, executable constructive procedure is also proposed for the controller design. Two simulation examples are exploited in order to illustrate the effectiveness of the proposed criteria as well as the controller design scheme. [ABSTRACT FROM AUTHOR]

In this study, the author investigates the input/output decoupling problem for Boolean control networks (BCNs). To keep up with the spirit of the original definition for linear state‐space models, that pertains the relationship between inputs and outputs independently of the state variables, two properties that formalise in different ways the idea that each single component of the output depends on the values of the corresponding input are provided, but not on the values of the other inputs. These properties are introduced by referring to the classical representation of a BCN in terms of Boolean input, state and output vectors, whose mutual relationships are expressed through the logical operators AND, OR and so on. In this set‐up, it is proven that there is some natural ordering among these properties, namely that one of them implies the other. In the second part of this study, it is shown that by resorting to the algebraic representation of BCNs a complete characterisation of these properties is possible. The algebraic characterisations obtained through this approach provide easy to check algorithms to evaluate whether a BCN is input/output decoupled or not. Finally, graph‐theoretic characterisations of the two input/output decoupling properties are provided. [ABSTRACT FROM AUTHOR]

Bulk quantity Boron Carbonitride (BCN) microspheres were successfully synthesized via an organic precursor pyrolysis approach. The organic precursor was synthesized at 90 °C by the polymerization reaction of boron trichloride，aniline and ethylenediamine with a molar ratio of 1:1:1. All particles presented uniform spherical structure with the size of 2 μm. The products have oxidation starting temperature at 624 °C much higher than graphene (404 °C). [ABSTRACT FROM AUTHOR]

[Display omitted] • Li decorated BCN monolayer has been investigated and show reversible hydrogen storage capacity under ambient temperature. • The Li can firmly anchor on BCN monolayer with binding energy of −1.91 eV. • The hydrogen storage capacity of Li @ BCN monolayer can reach up to 6.34 wt%. A novel 2D pm-BCN monolayer with unique porous geometry, superlight mass, and superior stability is a promising candidate for hydrogen storage. However, pure 2D materials suffer from the weak Van de Waals interaction between the H 2 , and modification becomes necessary to improve their performance. Here, we design a new complex by decorating active Li ions on the 2D pm-BCN substrate. The decoration of Li can transfer a partial electron to the substrate pm-BCN, which enhances the original π bonding among pm-BCN and induce more active sites on it. Both Li and BCN can act as the adsorption sites. The H 2 can realize reversible adsorption under an ambient condition with average adsorption energy of −0.20 eV/H 2 and a gravimetric capacity of 6.34 wt%, which surpasses the targe value set by U.S. Department of Energy (DOE). Rigorous analysis of its electronic properties, including a partial density of states, charge density, and crystal orbital overlap population, illustrates that the polarization mechanism contributes to the enhancement of the hydrogen storage capacity of Li@pm-BCN. [ABSTRACT FROM AUTHOR]

O objetivo deste trabalho é elaborar o balanço patrimonial de países com base nos cenários de mudanças climáticas e de aquecimento global apontados pelo Intergovernamental Panel on Climate Change (IPCC), da Organização das Nações Unidas (ONU). O estudo leva em consideração o estoque de recursos florestais e o saldo residual entre as emissões e capturas de carbono ou Greenhouse gas (GHG) estimadas para cada país, em 2020 e em 2050, de acordo com os relatórios Special Report on Emission Scenarios (SRES) A1B1 e A2B2. A pesquisa foi conduzida de forma multidisciplinar, envolvendo conceitos das áreas de biologia das mudanças climáticas, de energia, de geociência, de economia e da contabilidade. Esta última que foi utilizada para delimitar o objeto da pesquisa e servir de método, por meio da técnica Inquired Balance Sheet, para mensuração e classificação dos ativos, dos passivos e dos patrimônios líquidos ambientais. Selecionou-se uma amostra de sete países representantes do BRIC (Brasil, Rússia, Índia e China) e de países desenvolvidos da América, Europa e Ásia (EUA, Alemanha e Japão). Os balanços contábeis de cada país foram avaliados em unidades equivalentes de produto interno bruto (PIB), ajustados pelo consumo de energia per capita em toneladas equivalente de petróleo (TEP) e em mega toneladas de carbono (MtonC), precificadas pelo custo (US$) de captura de carbono sugeridos pela ONU. Os resultados da pesquisa mostram que os países desenvolvidos estão consumindo recursos de outras nações e de gerações futuras e, apesar de Brasil e Rússia apresentarem superávits ambientais, o balanço consolidado do planeta no cenário de 2050 aponta para uma situação deficitária ou falimentar, com "passivo a descoberto" ou patrimônio líquido negativo equivalente a US$ 2,3 mil anuais para cada um dos atuais 6,6 bilhões de habitantes (2008) e um passivo ambiental equivalente a um quarto do PIB mundial. Este relatório contábil não convencional é uma prestação de contas global diante dos cenários futuros e sugere ações coordenadas que envolvam aspectos sociais, ambientais, culturais e econômicos.

Facile fabrication of MOF derived C,N-ZnO and B doped g-C 3 N 4 nano - composite for photocatalytic CIP degradation and hydrogen evolution. [Display omitted] • MOF derived C/N-ZnO (CNZ) and B-g-C 3 N 4 (BCN) based composite photocatalyst. • CNZ/BCN nanocomposites are mesoporous in nature. • MOF derived strategy aids in-situ doping of C and N into ZnO lattice. • CNZ/BCN follows Z-scheme charge dynamics towards photocatalytic application. Herein, the fabrication of a robust CNZ/BCN nanocomposite is achieved by a facile in-situ calcination of ZIF - 8 along with BCN precursors. Morphologically the dodecahedral ZIF - 8 farmeworks are transformed into granular CNZ nanoparticles that were densely adhered to the BCN nanosheet surface with interfacial interactions. MOF derived strategy plays significant role in reducing the optical band gap via introducing C, N into the ZnO lattice as known from UV–vis-DRS as well as XPS studies. Additionally the composite formation lead to significantly enhanced exciton anti-recombination as suggested from EIS and PL analysis. The optimal CNZ/BCN (1:1) nanohybrid exhibits enhanced photocatalytic H 2 evolution rate of 7020 µmol h−1 g−1 which is nearly-two and eight folds greater than that of pristine CNZ and BCN respectively along with maximal ciprofloxacin photo-degradation rate (86.7 %). The radical trapping experiments deduced the formation of both superoxide and hydroxyl radicals that promotes the nanocomposite to follow Z - scheme charge transfer pathway during photocatalysis. Intermediates formed during CIP photo-degradation were identified by using LC-MS technique that showed ten intermediates formed through two different routes. Hence, MOF derived CNZ and BCN nanocomposite acts as a robust Z - scheme mediated photocatlyst that can be employed for varied energy and environmental purposes. [ABSTRACT FROM AUTHOR]

Structural, anisotropic, and thermodynamic properties of Imm2-BCN were studied based on density function theory with the ultrasoft psedopotential scheme in the frame of the generalized gradient approximation (GGA). The elastic constants were confirmed that the predicted Imm2-BCN is mechanically stable. The anisotropy of elastic properties were also studied systematically. The anisotropy studies of Young's modulus, shear modulus, linear compressibility, and Poisson's ratio show that the Imm2-BCN exhibits a large anisotropy. Through the quasi-harmonic Debye model, the relations between the equilibrium volume V, thermal expansion α, the heat capacity C and C , the Grüneisen parameter γ, and the Debye temperature Θ with pressure P and temperature T were also studied systematically. [ABSTRACT FROM AUTHOR]

Thin films of boron carbon nitride (BCN) are deposited by co-sputtering of B 4 C (Direct Current—DC) and BN (Radio frequency—RF) targets with varying N 2 /Ar gas flow ratio and DC target power. BCN being a low-k material and a potential inter layer dielectric (ILD), the deposition and surface analysis become prime factors for ultra large scale integration (ULSI) process and device integration. In this study, a thorough analysis on deposition rate of BCN thin films is conducted as a function of various N 2 /Ar gas flow ratios, target powers and substrate deposition temperatures. XPS studies are conducted to ascertain the chemical composition and bonding of the deposited BCN films for the various deposition parameters. The deposition rate is found to show a decreasing trend with an increase in substrate deposition temperature but showed an increasing trend at 400 °C. As the sputtering yield of B 4 C target is far greater than that of BN target, the deposition rate and XPS studies are conducted for the target powers of 20 W and 40 W for the B 4 C target. The deposition rate showed a decreasing trend from N 2 /Ar = 0.25 to 0.75, but increases at N 2 /Ar = 1. The XPS characterization indicates the formation of BCN phase distinctly with few separate phases of CN and BN. [ABSTRACT FROM AUTHOR]

• BCN was surface modified with two silane coupling agents. • Composites exhibited excellent properties before and after gamma irradiation. • The performance of composites can be improved by improving the interfacial compatibility. • Modified BCN could weaken oxidative degradation of EP under γ irradiation. Polymer matrix composites reinforced with boron nitride (BN) have attracted much attention in the nuclear industry due to their attractive properties. Nevertheless, the performance of such composites largely depends on matrix–filler interactions. Herein, carbon-doped boron nitride (BCN), modified by two silane coupling agents, was used to fabricate epoxy composites, and the effect of gamma irradiation on the properties of epoxy resin composites was investigated. The research showed that the modified BCN/epoxy composites prepared herein exhibited excellent mechanical and thermal properties before and after gamma irradiation. The tensile strength of the composites increased up to 63.1 MPa at 0.5 wt % loadings compared to neat epoxy (54.7 MPa). After irradiation at 900 kGy, the tensile strength of the composites was 32.5% higher than that of neat EP. This improvement was ascribed to the excellent compatibility of the modified BCN and epoxy. Moreover, the char yield and the glass transition temperature significantly increased with incorporation of modified BCN before and after irradiation. The mechanism for the enhanced performance was that the barrier consisting of BN protected the matrix from further oxidative degradation. This study suggested that functionalized BN more effectively enhanced epoxy properties before and after irradiation. [ABSTRACT FROM AUTHOR]

Three possible models of the ordered arrangement of B, C, and N atoms in chalcopyrite sublattices are considered. Crystal lattice parameters are obtained from the first principles, band spectra are calculated, and the role of B, C, and N atoms in the formation of chemical bonds and the valence band in the BCN, BCN, and BCN crystals is revealed. [ABSTRACT FROM AUTHOR]

A MoS2-RGO composite and borocarbonitride (BC5N) have been used as electrodes to selectively detect dopamine and uric acid in the presence of ascorbic acid. Both the electrodes show excellent eletrocatalytic activity towards the detection of dopamine, the detection limits being 0.55 μM and 2.1 μM in the case of MoS2-RGO and BCN respectively. MoS2-RGO shows a linear range of current over the 1-110 μM concentrations of dopamine, while BCN shows over the 2.3-20 μM range. BCN also exhibits satisfactory performance in the oxidation of uric acid with a detection limit of 3.8 μM and the linear range from 4 to 40 μM. The MoS2-RGO has also been used to detect adenine as well. [ABSTRACT FROM AUTHOR]

Boron Carbonitride (BCN) porous architectures build by carbon nanofibers and BCN precursor were successfully synthesized via a simple precursor pyrolysis method. Scanning electron microscope (SEM) and BET results showed the BCN porous architectures having the pore size distribution ringing from 50 nm to 24 microns in diameter. Fourier transform infrared (FT-IR) and X-ray diffractometer (XRD) results indicate that the products have the chemical composition of h-BCN and graphite. The minimum reflection loss and the frequency bandwidth below −20 dB for BCN are −56.2 dB and 7.7 GHz respectively, indicating better microwave absorption properties. [ABSTRACT FROM AUTHOR]