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• Notably enhanced Fe(III)/PMS process by trace Cu(II) was observed in BA buffer. • Cu(III) and Fe(IV) dominated in RhB removal while SO 4 •− and HO• played a minor role. • BA played a dual role of complexant and buffer in this Cu(II)/Fe(III)/PMS/BA system. • This iron-based AOP was applicable in water treatment under alkaline conditions. Dissolved copper and iron ions are regarded as friendly and economic catalysts for peroxymonosulfate (PMS) activation, however, neither Cu(II) nor Fe(III) shows efficient catalytic performance because of the slow rates of Cu(II)/Cu(I) and Fe(III)/Fe(II) cycles. Innovatively, we observed a significant enhancement on the degradation of organic contaminants when Cu(II) and Fe(III) were coupled to activate PMS in borate (BA) buffer. The degradation efficiency of Rhodamine B (RhB, 20 µmol/L) reached up to 96.3% within 10 min, which was higher than the sum of individual Cu(II)- and Fe(III)- activated PMS process. Sulfate radical, hydroxyl radical and high-valent metal ions (i.e., Cu(III) and Fe(IV)) were identified as the working reactive species for RhB removal in Cu(II)/Fe(III)/PMS/BA system, while the last played a predominated role. The presence of BA dramatically facilitated the reduction of Cu(II) to Cu(I) via chelating with Cu(II) followed by Fe(III) reduction by Cu(I), resulting in enhanced PMS activation by Cu(I) and Fe(II) as well as accelerated generation of reactive species. Additionally, the strong buffering capacity of BA to stabilize the solution pH was satisfying for the pollutants degradation since a slightly alkaline environment favored the PMS activation by coupling Cu(II) and Fe(III). In a word, this work provides a brand-new insight into the outstanding PMS activation by homogeneous bimetals and an expanded application of iron-based advanced oxidation processes in alkaline conditions. [ABSTRACT FROM AUTHOR]

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This study investigated the LAC, MAC, half-value thickness, tenth-value thickness, mean free path, Zeff, Neff, FNRCS, EBF, and EABF of a glass composition (70-x)B2O3 – 5TeO2 – 20SrO – 5ZnO – (x)Bi2O3, with x ranging from 0 to 15 mol%. Sample S5 showed the lowest HVT, TVT, and MFP and the highest MAC, LAC, Zeff, and Neff across 300 keV–15 MeV, indicating enhanced γ-ray shielding with higher Bi2O3 content in narrow-beam applications. However, EBF and EABF decreased with Bi2O3 at 0.5 and 1 MeV, but increased at 10 MeV, indicating improved shielding only at low and intermediate energies in broad-beam scenarios. Sample S4 exhibited the highest FNRCS and best neutron shielding efficiency. The comparison of our results with the literature revealed that S5 and S4 are, respectively, even more superior, in shielding γ radiation and neutrons than some of the glass materials that have been recently investigated in the literature. Therefore, in γ-ray shielding applications, incorporating Bi2O3 into the glass matrix is advisable primarily for narrow-beam conditions, and for broad-beam scenarios at intermediate energies, but not at high energies in broad-beam contexts. [ABSTRACT FROM AUTHOR]

The design and synthesis of hybrid borates by the organic ligand modification method are urgent and undeveloped areas of research. It is difficult to directly integrate organoboronic acids within inorganic borate chemistry by adopting the traditional preparation approaches. This work reports a facile synthetic method to synthesize a large family of pyrazole molecule‐protected borates in a rapid and precise manner under mild conditions. A unique cyclic eight‐membered B4O4‐ring has been identified as the cluster core for all these hybrid borates with two different conformations (boat and crown). This strategy can be applied to a system of pyrazolyl molecules to generate such hybrid borates in two independent routes from organoboronic or inorganic boric acids. Furtherly, the mechanism of 'click reaction' between boric acid and pyrazole induced by copper ions has been proposed based on the synthetic conditions and the structure of intermediate. Due to the bimetallic Cu sites and the functional surfaces, these materials can be used as electrocatalysts for CO2 reduction reaction and efficiently enhance the selectivity of HCOOH and C2H4. Our strategy can be regarded as a typical template technique for organic molecule‐protected borates. [ABSTRACT FROM AUTHOR]

In this study, a series of Sr6LuAl(BO3)6:Sm3+ red phosphors were successfully prepared with a high-temperature solid-phase technology. The Rietveld refinement analysis of the X-ray diffraction (XRD) diffraction patterns indicated that the as-prepared phosphors belong to the R 3 ¯ space group of the hexagonal crystal system. Under 404 nm near-ultraviolet excitation, the Sr6LuAl(BO3)6:Sm3+ phosphor exhibits narrowband emission within the range of 550 to 750 nm. The primary emission peak is observed at a wavelength of 599 nm, corresponding to 6H5/2 → 4F7/2. The optimum doping concentration of the Sr6LuAl(BO3)6:xSm3+ phosphor is 10 mol%. Nearest-neighbor ion interaction is the mechanism of concentration quenching. The synthesized phosphors demonstrate exceptional thermal stability, with a high quenching temperature (T0.5 > 480 K). Furthermore, the assembled white light-emitting diode (w-LED) device exhibits a low color temperature (5464 K), an excellent color rendering index (Ra = 95.6), and CIE coordinates (0.333, 0.336) close to those of standard white light. Collectively, these results suggest the enormous potential of Sr6LuAl(BO3)6:Sm3+ phosphors for applications in w-LEDs. [ABSTRACT FROM AUTHOR]

We report a convenient and diastereoselective copper‐catalyzed reductive alkynone aldol addition to aldehydes, with pinacolborane as stoichiometric reductant, that results in the generation of densely functionalized, trisubstituted (Z)‐enone products analogous to Morita‐Baylis‐Hillman adducts. We demonstrate that the reaction proceeds via an allenolborate, which we have characterized by NMR spectroscopy. A range of aromatic and aliphatic aldehydes can be reductively coupled with various non‐terminal alkynones. [ABSTRACT FROM AUTHOR]

The range between boron deficiency and toxicity in plants is utterly narrow, so that the certain dose of boron fertilizer is required for plants. Indicators of optimum boron fertilization can be measured from plant production and boron use efficiency (BUE) value. BUE influenced by the amount of soluble B-soil, type of B fertilizer, amount of boron input, type of plant, and adequacy of available macronutrients (NPK). However, excessive application of NPK base fertilizer from inorganic fertilizers can trigger soil degradation. Currently, there has not been much research that measures the reduction in the dose of NPK base fertilizer combined with boron fertilizer on plant BUE. The combination of reducing the dose of NPK base fertilizer and boron fertilizer was tested on sweet corn plants on production and BUE. This study was conducted with a randomized block design with 7 treatments, namely without fertilization (K0), base fertilization (D1), 100% base fertilization and 50–15% borate (D2–D4), and 75% base fertilization and 50–15% borate (D5–D7). The results of the initial soil analysis showed low boron content in the soil, so borate fertilization was required to provide nutrients for sweet corn plants. Application of NPK base fertilizer (100%) and addition of borate fertilizer at a dose of 50-100% (~3-6 kg/ha) significantly increased growth, plant biomass, B uptake, boron recovery efficiency (BRE), and B fertilizer efficiency ratio, compared to lower NPK-base fertilizer. Based on the estimated response curve, the recommended dose to achieve optimum-maximum sweet corn production and maximum boron recovery efficiency is 100% macro inorganic fertilization (urea, SP-36, KCl) combined with 5.72-6.75 kg/ha borate fertilizer.

Here, we elaborate a borate glass system with x La 2 O 3 – (79-x) B 2 O 3 – 20.6 Na 2 O – 0.4 CoO; (x = 0, 3, 6 and 9 mol%) glass composition utilizing the melt-quenching method, and studied through density, basic physical parameters, Fourier transforms-infrared (FTIR) and optical absorption spectroscopy. Further addition of La 2 O 3 , up to 9 mol%, affords an enhancement (25 %) in the glass density, besides other structural parameters revealing the role of lanthanum ions on the glass matrix. FTIR findings revealed the essential structural groups of borate glass like trigonal BO 3 units, tetrahedra BO 4 units, and non-bridging oxygen atoms. Here too, a propensity towards the transformation from BO 3 units to BO 4 units was obtained. The optical absorption spectra revealed the existence of Co2+ in octahedral and tetrahedral coordination and the presence of Co3+ in octahedral coordination. The blue color of the present glass was attributed to the absorption band at 571.6–580.9 nm of Co2+ cation within the tetrahedral complexes. Further analysis of the ligand field parameters revealed increased values of the splitting energy parameter of Co2+ in a tetrahedral field with higher La 2 O 3 doping indicating a higher interplay between Co cations and their surrounding ligands. Additionally, the other ligand field parameters described the environments around the cobalt ions such as bonding nature. Finally, the glass refractive index increased with the further addition of lanthanum oxide, enhancing the glass quality for the optical realm. These reported findings show excellent properties of glass host as a promising contender in optical applications. [ABSTRACT FROM AUTHOR]

Discovery of new materials with enhanced optical properties in the visible and UV‐C range can impact applications in lasers, nonlinear optics, and quantum optics. Here, the optical floating zone growth of a family of rare earth borates, RBa3(B3O6)3 (R = Nd, Sm, Tb, Dy, and Er), with promising linear and nonlinear optical (NLO) properties is reported. Although previously identified to be centrosymmetric, the X‐ray analysis combined with optical second harmonic generation (SHG) assigns the noncentrosymmetric P6¯$\overline{6}$ space group to these crystals. Characterization of linear optical properties reveals a direct bandgap of ≈5.61–5.72 eV and strong photoluminescence in both the visible and mid‐IR regions. Anisotropic linear and nonlinear optical characterization reveals both Type‐I and Type‐II SHG phase matchability, with the highest effective phase‐matched SHG coefficient of 1.2 pm V−1 at 800‐nm fundamental wavelength (for DyBa3(B3O6)3), comparable to β‐BaB2O4 (phase‐matched d22 ≈ 1.9 pm V−1). Laser‐induced surface damage threshold for these environmentally stable crystals is 650–900 GW cm−2, which is four to five times higher than that of β‐BaB2O4, thus providing an opportunity to pump with significantly higher power to generate about six to seven times stronger SHG light. Since the SHG arises from disorder on the Ba‐site, significantly larger SHG coefficients may be realized by "poling" the crystals to align the Ba displacements. These properties motivate further development of this crystal family for laser and wide bandgap NLO applications. [ABSTRACT FROM AUTHOR]

STACK family borates are promising compounds for optical applications. Synthesis and luminescence of Sr3Y(BO3)3 borate belonging to the STACK family is described. Trivalent activators Tb3+ and Gd3+ occupy yttrium sites. Owing to fixed, well-separated positions (Y–Y distance 7.396 Å), a large concentration of Gd3+, as much as 50% relative to Y, could be accommodated without causing concentration quenching. In the case of Gd3+, both excitation and emission lines arise in f–f transitions. Photoluminescence emission is obtained in UV regions. In the case of Tb3+, concentration quenching was observed above 2%. Prominent excitation of Tb3+ is in the form of a band arising in the f–d-type transition, while emission comes from f–f transitions. Emission lifetimes are of the order of milliseconds, typically forbidden f–f transitions. [ABSTRACT FROM AUTHOR]

The effects of FetO on the characteristic melting temperature, viscosity, and structure of Na2O3-B2O3-CaO-SiO2-Al2O3 slag were investigated. Understanding the viscous behavior and structure of borate slag containing FetO can guide the design of mold powders for copper alloy casting. The melting temperature (Th) suddenly increased and exceeded 800 °C when the FetO content increased from 15 to 23 wt%. The viscosity changed significantly with increasing FetO content when the temperature was below 1050 °C. The slag structure exhibited a boron–iron anomaly. The viscosity of the Na2O3-B2O3-CaO-SiO2-Al2O3 slag gradually increased with increasing FetO content. When the content of FetO was low, sufficient oxygen in the slag promoted iron and boron to enter the network structure in the form of [FeO4] and [BO4], thereby reducing free oxygen and free [BO3]. As the FetO content exceeded a certain value, free oxygen decreased proportionally, and some iron ions existed in the form of [FeO6] with the network modifiers. Simultaneously, the amount of free [BO3] that is not bound to oxygen increased. Based on the optical basicity viscosity prediction model, the viscosity of borate slag with high iron content was predicted, and the M–O bond strength reflected by optical basicity was closer than the strength predicted for the network structure based on slag viscosity. [ABSTRACT FROM AUTHOR]

STACK family borates are promising compounds for optical applications. Synthesis and luminescence of Sr3Y(BO3)3 borate belonging to the STACK family is described. Trivalent activators Tb3+ and Gd3+ occupy yttrium sites. Owing to fixed, well-separated positions (Y–Y distance 7.396 Å), a large concentration of Gd3+, as much as 50% relative to Y, could be accommodated without causing concentration quenching. In the case of Gd3+, both excitation and emission lines arise in f–f transitions. Photoluminescence emission is obtained in UV regions. In the case of Tb3+, concentration quenching was observed above 2%. Prominent excitation of Tb3+ is in the form of a band arising in the f–d-type transition, while emission comes from f–f transitions. Emission lifetimes are of the order of milliseconds, typically forbidden f–f transitions. [ABSTRACT FROM AUTHOR]

Treatment of [Cp*TiCl3] with [LiBH4 ⋅ THF] followed by thermolysis with [Ph2E2] (E=S or Se) resulted in the formation of classical diborane(6) complexes, [(Cp*Ti)(η4‐B2H4LL′)] (L=C6H4E; L′=C6H5E; 1 a: E=S, 1 b: E=Se), stabilized at titanium template. To the best of our knowledge, they are the first examples of mono‐metallic classical diborane(6) complexes. The bonding analysis and theoretical studies suggest that the stabilization of these diborane(6) species is due to the presence of four bridging ligands in ĸ4‐fashion, where two of them are phenyl thiolates/selenolates that provide more electrons to the electron‐deficient titanium center. Reactions of these diborane(6) species with [M(CO)5 ⋅ THF] (M=Mo, W) led to the cleavage of the electron‐precise B(sp3)−B(sp3) bond that yielded ĸ3‐hydridoborato complexes [(Cp*Ti)(ĸ3‐BH3R)(μ‐EPh)2{M(CO)4}] (2 a–c: R=H, 3 a–c: R=Ph). In an attempt to isolate the Te‐analogue of 1 a–b, a similar reaction was performed; however, the complex was too unstable to be isolated. Interestingly, the treatment of this unstable intermediate with [W(CO)5 ⋅ THF] yielded [(Cp*Ti)(ĸ3‐BH3R)(μ‐TePh)2{W(CO)4}] (2 d: R=H, 3 d: R=Ph) that are analogues of 2 a–c and 3 a–c, respectively. Formation of these species provide indirect evidence for the existence of unstable [(Cp*Ti)(η4‐B2H4LL′)] (L=C6H4Te; L′=C6H5Te; 1 c). [ABSTRACT FROM AUTHOR]

A mixed transition metal borate Co5–xVxCoy[B12O26–z(OH)z] was synthesized in a Walker-type module using the high-pressure/high-temperature approach at 12 GPa and 1,300 °C. The product crystallizes in the space group I41/acd. It is isotypic to other 3d metal cation borates of the M5[B12O25(OH)]–M5M[B12O22(OH)4] solid solution series. The title compound features three different metal cation positions; one octahedral site contains a mixture of V and Co, another octahedral site is fully occupied with Co, and a cuboctahedral position that is partially occupied with Co. It is the first compound within this structure type to contain Co, increasing the range of elements that can be incorporated and thus illustrating the adaptability and structural diversity of this anionic borate network. [ABSTRACT FROM AUTHOR]

A mixed transition metal borate Co5–xVxCoy[B12O26–z(OH)z] was synthesized in a Walker-type module using the high-pressure/high-temperature approach at 12 GPa and 1,300 °C. The product crystallizes in the space group I41/acd. It is isotypic to other 3d metal cation borates of the M5[B12O25(OH)]–M5M[B12O22(OH)4] solid solution series. The title compound features three different metal cation positions; one octahedral site contains a mixture of V and Co, another octahedral site is fully occupied with Co, and a cuboctahedral position that is partially occupied with Co. It is the first compound within this structure type to contain Co, increasing the range of elements that can be incorporated and thus illustrating the adaptability and structural diversity of this anionic borate network. [ABSTRACT FROM AUTHOR]

Abstract This contribution investigates the effect of variable copper incorporation (x = 0.2, 1.0, 2.0, and 4.0) in silicate (45 SiO2, 24.5 CaO, 24.5 Na2O, 6P2O5 wt%) and modified borate (45 B2O3, 24.5 CaO, 24.5 Na2O, 6P2O5 wt%) bioglass materials to be used for bone bonding applications. X-ray absorption fine structure spectroscopy (XAFS) has been used to determine the oxidation states and local coordination structure of Cu atoms in silicate-based and borate-based glasses at the Cu K-edge (~ 8979 eV). The oxidation states of Cu atoms have been determined by near-edge XAFS (XANES) fingerprinting employing reference standard compounds of Cu. Cu (I) and Cu (II) XANES spectra of the standard reference compounds were linearly combined to fit the normalized μ(E) data of the collected XANES spectra using linear combination fitting (LCF approach). The obtained results prove that most of the silicate glass samples contain Cu2O almost exclusively, while modified borate glass samples contain a significant mixture of Cu2O and CuO phases. According to the literature, the remarkable coexistence of Cu2O and CuO phases within the borate sample, particularly when x = 4, promotes the conversion process to allow the more facile formation of hydroxy carbonate apatite (HCA). The best fit structural parameters derived from extended-XAFS (EXAFS) fitting show that the ratio between Cu (I) and Cu (II) in borate glass agreed well with that extracted from XANES analysis. XANES and EXAFS conclude that borate glass with x = 4 is the most suitable composition for bone bonding applications.

Fabricating efficient adsorbent for the removal of nuclear waste is of vital importance from the viewpoint of both environmental protection and resource reclamation. Published research has yielded several adsorbents; however, these reported materials do not possess a high removal performance for different types of nuclear waste. In this work, it is shown for the first time the synthesis of a boron‐functionalized covalent organic framework (COF) and its ionic borate counterpart. These boron‐functionalized COFs are found to show large potential for handling various nuclear wastes, including alkaline nuclear wastewater, uranium‐containing nuclear wastewater, and I2 nuclear off‐gas. The developed COF has a record NaOH uptake of 2 g g−1, an ultrahigh uranium extraction ability of 1.77 g g−1, and an ultrahigh I2 capture capacity of 9.4 g g−1. Moreover, the materials have low cost and are reusable, and thus have significant potential for handling nuclear wastes. [ABSTRACT FROM AUTHOR]

A new type of diborate clathrochelate (cage) ligand featuring nine inwardly pointing nitrogen donors that form a large, rigid cavity, termed a mausolate, is presented. The cavity size and high denticity make this an attractive delivery vehicle for large radionuclides in nuclear medicine. Metal mausolate complexes are stable to air and water (neutral pH) and display extremely high thermal stability (>400 °C). Lanthanide uptake by the mausolate ligand occurs rapidly in solution at room temperature and once complexed, the lanthanide ions are not displaced by a 250‐fold excess of a competitive lanthanide salt over more than one week. [ABSTRACT FROM AUTHOR]

This contribution investigates the effect of variable copper incorporation (x = 0.2, 1.0, 2.0, and 4.0) in silicate (45 SiO2, 24.5 CaO, 24.5 Na2O, 6P2O5wt%) and modified borate (45 B2O3, 24.5 CaO, 24.5 Na2O, 6P2O5wt%) bioglass materials to be used for bone bonding applications. X-ray absorption fine structure spectroscopy (XAFS) has been used to determine the oxidation states and local coordination structure of Cu atoms in silicate-based and borate-based glasses at the Cu K-edge (~ 8979 eV). The oxidation states of Cu atoms have been determined by near-edge XAFS (XANES) fingerprinting employing reference standard compounds of Cu. Cu (I) and Cu (II) XANES spectra of the standard reference compounds were linearly combined to fit the normalized μ(E) data of the collected XANES spectra using linear combination fitting (LCF approach). The obtained results prove that most of the silicate glass samples contain Cu2O almost exclusively, while modified borate glass samples contain a significant mixture of Cu2O and CuO phases. According to the literature, the remarkable coexistence of Cu2O and CuO phases within the borate sample, particularly when x = 4, promotes the conversion process to allow the more facile formation of hydroxy carbonate apatite (HCA). The best fit structural parameters derived from extended-XAFS (EXAFS) fitting show that the ratio between Cu (I) and Cu (II) in borate glass agreed well with that extracted from XANES analysis. XANES and EXAFS conclude that borate glass with x = 4 is the most suitable composition for bone bonding applications. [ABSTRACT FROM AUTHOR]

Borates have garnered a lot of attention in the realm of solid‐state chemistry due to their remarkable characteristics, in which the synthesis of borates with isolated [BO3] by adding rare‐earth elements is one of the main areas of structural design study. Five new mixed‐metal Y‐based rare‐earth borates, Ba2ZnY2(BO3)4, KNa2Y(BO3)2, Li2CsY4(BO3)5, LiRb2Y(BO3)2, and RbCaY(BO3)2, have been discovered using the high‐temperature solution approach. Isolated [BO3] clusters arranged in various configurations comprise their entire anionic framework, allowing for optical anisotropy tuning between 0.024 and 0.081 under 1064 nm. In this study, we characterize the relative placements of their [BO3] groups and examine how their structure affects their characteristics. The origin of their considerable optical anisotropy has been proven theoretically. This study unequivocally demonstrates that even a slight alteration to borates′ anionic structure can result in a significant improvement in performance. [ABSTRACT FROM AUTHOR]

We present the synthesis, characterization, and crystal structure of sodium tetrabenzylborate, a novel tetraalkoxyborate obtained via a direct mechanochemical reaction between benzaldehyde and sodium borohydride at room temperature. The molecular and crystal structures of this borate were investigated using 11B MAS NMR, IR spectroscopy, differential scanning calorimetry (DSC), and X-ray diffraction (XRD) analyses. Crystalline sodium tetrabenzylborate exists in two different crystal structures, which were elucidated using powder- and single-crystal-XRD analyses. At a low temperature (e.g., −100 °C), sodium tetrabenzylborate crystallizes in the monoclinic system with the space group P21 (No. 4), but at room temperature, it displays a crystallization in the tetragonal system with the space group I 4 ¯ (No. 82). According to the DSC analysis, the phase transition occurs at −45 °C. Upon hydrolysis, sodium tetrabenzylborate undergoes direct transformation into benzyl alcohol, thereby confirming the ability of sodium borohydride to convert an aldehyde into its primary alcohol analog. The key findings from our analyses are presented herein. [ABSTRACT FROM AUTHOR]

As a fundamental parameter of the optical crystals, birefringence plays a vital role in many optical applications, such as phase modulation, light splitting, and polarization, especially the phase matching process of the nonlinear optical crystals. The big birefringence not only benefits to the miniaturization of related devices, but also broadens the phase-matching wavelength range of nonlinear optical crystals. The design and synthesis of crystals with large birefringence becomes a hot research topic due to its more and more important applications in the optical modulation and laser technology fields. Herein, crystals with birefringence greater than 0.05 in the borate system are reviewed and classified according to different birefringent active groups, and the relationship between structure and properties is thoroughly explored. It is hoped that this review will provide a clear understanding of what kinds of building units and arrangements would have more opportunity to get adequate birefringence in borate systems and provide the statistical references to encourage the emergence of better crystal materials with large birefringence. [ABSTRACT FROM AUTHOR]

The robust electronegativity of the [BO3]3− structure enables the extraction of electrons from adjacent metals, offering a strategy for modulating oxygen activation in propane oxidative dehydrogenation. Metals (Ni 1.91, Al 1.5, and Ca 1.0) with varying electronegativities were employed to engineer borate catalysts. Metals in borate lacked intrinsic catalytic activity for propane conversion; instead, they modulated [BO3]3− group reactivity through adjustments in electron density. Moderate metal electronegativity favored propane oxidative dehydrogenation to propylene, whereas excessively low electronegativity led to propane overoxidation to carbon dioxide. Aluminum, with moderate electronegativity, demonstrated optimal performance. Catalyst AlBOx-1000 achieved a propane conversion of 47.5%, with the highest propylene yield of 30.89% at 550 °C, and a total olefin yield of 51.51% with a 58.92% propane conversion at 575 °C. Furthermore, the stable borate structure prevents boron element loss in harsh conditions and holds promise for industrial-scale catalysis. [ABSTRACT FROM AUTHOR]

A wide variety of borate materials are emerging as photocatalysts. Usually, the borates possess a large bandgap which limits their absorption of visible light, and the strategy of preparing nanocomposites is an effective way to enhance the absorption of light. X‐ray powder diffraction, infrared spectroscopy, Raman spectroscopy, scanning electron microscopy, and transmission electron microscopy were used to show that a three‐component nanocomposites was successfully prepared. For the photo‐degraded reactions of rhodamine B(RhB) and doxycycline hydrochloride(DH), the optimum composition of the ternary composite is a molar ratio of Gd0.9Ce0.1B5O9(GCBO) and g‐C3N4(CN) of 7 : 93, besides the mass of Cu is 2 % of the sum of the above two masses, and the ternary composite is abbreviated as 2Cu/CN@GCBO‐7. The kinetic constant for the photodegradation of RhB of sample 2Cu/CN@GCBO‐7 is 0.0580 min−1, which is 3.6 and 3.8 times that of non‐composite CN and GCBO. The mechanism postulated by free radical quenching experiments suggests that the importance of the three radicals is hole >⋅OH>⋅O2− in the photodegradation reaction. In addition, the kinetic constant for the photodegradation of DH of sample 2Cu/CN@GCBO‐7 is 0.0018 min−1, and the sample 2Cu/CN@GCBO‐7 has a hydrogen evolution rate of 11.8 μmol/h/g. [ABSTRACT FROM AUTHOR]

This report presents work on the orthorhombic phases Ln2CdB5O11(OH) (Ln = Tm, Lu). The title compounds were synthesized in a Walker-type multianvil device at 7 GPa and 650 °C, and the resulting samples were thoroughly investigated through single-crystal and powder X-ray diffraction methods. Lu2CdB5O11(OH) crystallizes in the space group Pmna (no. 53) with the unit cell parameters a = 12.772(2), b = 4.6017(7), and c = 12.481(2) Å. Similar unit cell parameters are observed for the isotypic Tm analogue compound. The crystals have a layered crystal structure built up by four-, five-, and eight-membered rings of corner-sharing [BO4] tetrahedra. The structural data are accompanied by attenuated total reflection (ATR) infrared spectra and energy-dispersive X-ray spectroscopy (EDX). [ABSTRACT FROM AUTHOR]

B2O3 was used as a fluxing agent can reduce the melting temperature of municipal solid waste incineration (MSWI) fly ash which related to the formation of the minerals Ca3(BO3)2, Ca2B2O5 and CaB2O4 during vitrification process. However, the relationship between immobilization of heavy metals and borates transformation during melting process remains unclear. In this study, the immobilization of heavy metal Pb inside Ca3(BO3)2, Ca2B2O5 and CaB2O4 based on density functional theory (DFT) were comparatively studied in this paper. The results showed that the defect formation energies for substitutional doping model are higher than interstitial model which is the more favorable the immobilization model for Pb. Pb cause a volume expansion in all borates. In the substitution doping model, Pb can replace Ca to balance the electronegativity of O atom and form chemical bonds with the surrounding O atoms, and the covalency of Pb–O is stronger than that of Ca–O. In addition, the order of covalency between Pb and surrounding O atoms is as follows: Ca3(BO3)2 > Ca2B2O5 > CaB2O4. In the interstitial doping model, bonds of O–Pb and B-Pb exhibited negative population values, revealing that filling of electrons into the antibonding states was the major orbital contribution. In addition, B 2s and 2p orbital and Pb 6p orbital form hybridization near the Fermi level in the CaB2O4 (I) doping model. [ABSTRACT FROM AUTHOR]

The article describes the synthesis of diborane(6)-dianions decorated with weakly coordinating B(C6F5)3- and SiEt3+ groups. Two compounds were isolated, which demonstrate the synthetic potential and chemical versatility of the dianions. The functionalization of the dianions is of interest for stabilizing reactive dications and modulating the properties of salts with reactive cations. The thermal stability, bond lengths, and electronic properties of the compounds were investigated and confirmed by spectroscopic and electrochemical measurements. The results show that the functionalization of the diborane(6)-dianions leads to new properties. [Extracted from the article]

Sodium diborate glasses containing cadmium and lead oxides were fabricated by the melt annealing technique. Lead oxide was introduced at the expense of cadmium oxide to enhance its elastic and shielding properties. The density of the lead-free glass increased from 2.137 g/cm³ to 3.330 g/cm³ after replacing cadmium oxide with lead oxide. The density values were used to investigate the elastic properties of glass using the Makishima-Mackenzie model. In addition, the Phy-X/PSD code was used to simulate the shielding properties of such glasses at different photon energies ranging from 0.005 to 15 MeV. [ABSTRACT FROM AUTHOR]

Two novel metal borates, namely, Ag7B9O16(OH)2 (1) and AgCa2B7O11(OH)4 (2) were obtained under hydrothermal conditions. Ag7B9O16(OH)2 crystallizes into the centrosymmetric space group of C2/c in the monoclinic crystal system and displays a unique three‐dimensional (3D) framework built by 1D double borate chains further connected by Ag cations. AgCa2B7O11(OH)4 also belongs to monoclinic space group C2/c and it features borate chains with B8O8 8‐membered rings along the c axis which are further coordinated via AgO3 into 2D layers. These layers are bridged via CaO8 polyhedron into the final 3D framework. Two compounds were further characterized through thermogravimetric and optical analysis and density functional theory calculation have also been carried out, addressing their electronic structures. [ABSTRACT FROM AUTHOR]

The substitution of fluorine atoms for oxygen atoms/hydroxyl groups has emerged as a promising strategy to enhance the physical and chemical properties of oxides/hydroxides in fluorine chemistry. However, distinguishing fluorine from oxygen/hydroxyl in the reaction products poses a significant challenge in existing characterization methods. In this study, we illustrate that terahertz (THz) spectroscopy provides a powerful tool for addressing this challenge. To this end, we investigated two fluorination reactions of boric acid, utilizing MHF2 (M=Na, C(NH2)3) as fluorine reagents. Through an interplay between THz spectroscopy and solid‐state density functional theory, we have conclusively demonstrated that fluorine atoms exclusively bind with the sp3‐boron but not with the sp2‐boron in the reaction products of Na[B(OH)3][B3O3F2(OH)2] (NaBOFH) and [C(NH2)3]2B3O3F4OH (GBF2). Based on this evidence, we have proposed a reaction pathway for the fluorinations under investigation, a process previously hindered due to structural ambiguity. This work represents a step forward in gaining a deeper understanding of the precise structures and reaction mechanisms involved in the fluorination of oxides/hydroxides, illuminated by the insights provided by THz spectroscopy. [ABSTRACT FROM AUTHOR]

The development of novel photocatalysts, both visible and UV-responsive, for water decomposition reactions is of great importance. Here we focused on the application of the borates as photocatalysts in water decomposition reactions, including water splitting reaction, hydrogen evolution half-reaction, and oxygen evolution half-reaction. In addition, the rates of photocatalytic hydrogen evolution and oxygen evolution by these borate photocatalysts in different water decomposition reactions were summarized. Further, the review summarized the synthetic chemistry and structural features of existing borate photocatalysts for water decomposition reactions. Synthetic chemistry mainly includes high-temperature solid-state method, sol-gel method, precipitation method, hydrothermal method, boric acid flux method, and high-pressure method. Next, we summarized the crystal structures of the borate photocatalysts, with a particular focus on the form of the B-O unit and metal-oxygen polyhedral in the borates, and used this to classify borate photocatalysts, which are rarely mentioned in the current photocatalysis literature. Finally, we analyzed the relationship between the structural features of the borate photocatalysts and photocatalytic performance to discuss the further challenges faced by the borate photocatalysts for water decomposition reactions. [ABSTRACT FROM AUTHOR]

The effect of ultrasound energy on hydrothermal synthesis of metal borates and on the characteristic features of synthesized copper borates was investigated. In ultrasonic-assisted hydrothermal synthesis, the reaction parameters such as boron source, reaction temperature and time were optimized. The synthesis was achieved in the modest conditions of 60°C—2.5 min and 70°C—15 min for the boron sources borax and tincalconite, respectively. The obtained phases were identified as the compound of copper borate (Cu(BO2)2) with the powder diffraction file no. 00-001-0472. The reaction yields were also increased from 48 to 75% with modification of experimental procedure. The observed characteristic stretchings in spectral analyses proved the functional groups of three and four coordinated boron to oxygen bands. In the morphological analyses, less agglomerates were observed at the samples produced by using the boron source of borax than tincalconite. The results exhibited the beneficial effects of probable usage of the ultrasound energy on both the practical synthesis and the increase of characteristics. [ABSTRACT FROM AUTHOR]

TbGa3(BO3)4 crystals were grown using the Bi2Mo3O12:B2O3:Tb2O3 flux, which decreases contamination of Bi in the resulting crystal. The produced compound crystallizes in the R32 space group with unit cell parameters: a = 9.4512(4) Å, c = 7.4532(2) Å. A strong green emission of the luminescence is primarily dominated by the 5D4 to 7F5 transition in Tb3+. Annealing these crystals in a hydrogen atmosphere at 800 °C causes a reduction in the luminescence efficiency. On the other hand, annealing in air results in the increment of QY up to the value of 38%. [ABSTRACT FROM AUTHOR]

Addressing periprosthetic infections, which present significant healing challenges that often require revision surgeries, necessitates the development of novel antibacterial materials and implants. Current research focuses on creating materials that hinder bacterial adhesion, colonization, and proliferation in surrounding tissues. Boron (B)-containing compounds are known for their antibacterial properties and potential in bone metabolism for regenerative medicine. In this study, we synthesized B-containing tricalcium phosphate (0.3B-TCP) with 1.1 wt.% B content via precipitation from aqueous solutions and sintering at 1100 °C. X-ray diffraction confirmed the ceramic's primary crystalline phase as β-TCP, with B evenly distributed according to energy-dispersive spectroscopy data. Electron paramagnetic resonance (EPR) data verified stable paramagnetic borate anions, indicating successful BO33− substitution for phosphate groups. The microstructural properties of 0.3B-TCP ceramic were assessed before and after soaking in a saline solution. Its bending strength was approximately 30 MPa, and its porosity was about 33%. 0.3B-TCP ceramic demonstrated significant antimicrobial efficacy against various bacterial strains and a fungus. Cytotoxicity evaluation using equine adipose tissue-derived mesenchymal stem cells and osteogenic differentiation assessment were conducted. The combination of antibacterial efficacy and good cytocompatibility suggests 0.3B-TCP ceramic as a promising bone substitute material. [ABSTRACT FROM AUTHOR]

This investigation involved an ab initio and Density Functional Theory (DFT) analysis of the hydrolysis mechanism and energetics in a borate network. The focus was on understanding how water molecules interact with and disrupt the borate network, an area where the experimental data are scarce and unreliable. The modeled system consisted of two boron atoms, bridging oxygen atoms, and varying numbers of water molecules. This setup allows for an exploration of hydrolysis under different environmental conditions, including the presence of OH− or H+ ions to simulate basic or acidic environments, respectively. Our investigation utilized both ab initio calculations at the MP2 and CCSD(T) levels and DFT with a range of exchange–correlation functionals. The findings indicate that the borate network is significantly more susceptible to hydrolysis in a basic environment, with respect to an acidic or to a neutral pH setting. The inclusion of explicit water molecules in the calculations can significantly affect the results, depending on the nature of the transition state. In fact, some transition states exhibited closed-ring configurations involving water and the boron–oxygen–boron network; in these cases, there were indeed more water molecules corresponding to lower energy barriers for the reaction, suggesting a crucial role of water in stabilizing the transition states. This study provides valuable insights into the hydrolysis process of borate networks, offering a detailed comparison between different computational approaches. The results demonstrate that the functionals B3LYP, PBE0, and wB97Xd closely approximated the reference MP2 and CCSD(T) calculated reaction pathways, both qualitatively in terms of the mechanism, and quantitatively in terms of the differences in the reaction barriers within the 0.1–0.2 eV interval for the most plausible reaction pathways. In addition, CAM-B3LYP also yielded acceptable results in all cases except for the most complicated pathway. These findings are useful for guiding further computational studies, including those employing machine learning approaches, and experimental investigations requiring accurate reference data for hydrolysis reactions in borate networks. [ABSTRACT FROM AUTHOR]

We report on the synthesis, structure determination, and characterization of a new series of compounds LnCdB6O10(OH)3 (Ln = Sm–Er). Syntheses were carried out in a Walker-type multianvil device at 7 GPa and 650 °C. Structure determinations revealed the coexistence of an orthorhombic and a monoclinic polymorph, depending on the ionic radius of the lanthanoid cation. The orthorhombic structural variants crystallize non-centrosymmetrically in the space group Pna21 (no. 33), while the monoclinic modifications crystallize in space group P21/c (no. 14). Both modifications display a layered crystal structure built up by a repeating [B6O13]8− building block as their main structural feature. [ABSTRACT FROM AUTHOR]