OH Anions Research Articles

A self-supplied hydrogen peroxide and nitric oxide-generating nanoplatform enhances the efficacy of chemodynamic therapy for biofilm eradication

Bacterial biofilms present a profound challenge to global public health, often resulting in persistent and recurrent infections that resist treatment. Chemodynamic therapy (CDT), leveraging the conversion of hydrogen peroxide (H2O2) to highly reactive hydroxyl radicals (•OH), has shown potential as an antibacterial approach. Nonetheless, CDT struggles to eliminate biofilms due to limited endogenous H2O2 and the protective extracellular polymeric substances (EPS) within biofilms. This study introduces a multifunctional nanoplatform designed to self-supply H2O2 and generate nitric oxide (NO) to overcome these hurdles. The nanoplatform comprises calcium peroxide (CaO2) for sustained H2O2 production, a copper-based metal–organic framework (HKUST-1) encapsulating CaO2, and l-arginine (l-Arg) as a natural NO donor. When exposed to the acidic microenvironment within biofilms, the HKUST-1 layer decomposes, releasing Cu2+ ions and l-Arg, and exposing the CaO2 core to initiate a cascade of reactions producing reactive species such as H2O2, •OH, and superoxide anions (•O2–). Subsequently, H2O2 catalyzes l-Arg to produce NO, which disperses the biofilm and reacts with •O2– to form peroxynitrite, synergistically eradicating bacteria with •OH. In vitro assays demonstrated the nanoplatform’s remarkable antibiofilm efficacy against both Gram-positive Methicillin-resistant Staphylococcus aureus and Gram-negative Pseudomonas aeruginosa, significantly reducing bacterial viability and EPS content. In vivo mouse model experiments validated the nanoplatform’s effectiveness in eliminating biofilms and promoting infected wound healing without adverse effects. This study represents a breakthrough in overcoming traditional CDT limitations by integrating self-supplied H2O2 with NO’s biofilm-disrupting capabilities, offering a promising therapeutic strategy for biofilm-associated infection.

Effect of chemical abrasion of zircon on SIMS U–Pb, δ18O, trace element, and LA-ICPMS trace element and Lu–Hf isotopic analyses

Abstract. This study assesses the effect of chemical abrasion on in situ mass spectrometric isotopic and elemental analyses in zircon. Chemical abrasion improves the U–Pb systematics of SIMS (secondary ion mass spectrometry) analyses of reference zircons, while leaving other isotopic systems largely unchanged. SIMS 206Pb/238U ages of chemically abraded reference materials TEMORA-2, 91500, QGNG, and OG1 are precise to within 0.25 % to 0.4 % and are within uncertainty of chemically abraded TIMS (thermal ionization mass spectrometry) reference ages, while SIMS 206Pb/238U ages of untreated zircons are within uncertainty of TIMS reference ages where chemical abrasion was not used. Chemically abraded and untreated zircons appear to cross-calibrate within uncertainty using all but one possible permutation of reference materials, provided that the corresponding chemically abraded or untreated reference age is used for the appropriate material. In the case of reference zircons QGNG and OG1, which are slightly discordant, the SIMS U–Pb ages of chemically abraded and untreated material differ beyond their respective 95 % confidence intervals. SIMS U–Pb analysis of chemically abraded zircon with multiple growth stages is more difficult to interpret. Treated igneous rims on zircon crystals from the S-type Mount Painter Volcanics are much lower in common Pb than the rims on untreated zircon grains. However, the analyses of chemically abraded material show excess scatter. Chemical abrasion also changes the relative abundance of the ages of zircon cores inherited from the sedimentary protolith, presumably due to some populations being more likely to survive the chemical abrasion process than others. We consider these results from inherited S-type zircon cores to be indicative of results for detrital zircon grains from unmelted sediments. Trace element, δ18O, and εHf analyses were also performed on these zircons. None of these systems showed substantial changes as a result of chemical abrasion. The most discordant reference material, OG1, showed a loss of OH as a result of chemical abrasion, presumably due to dissolution of hydrous metamict domains or thermal dehydration during the annealing step of chemical abrasion. In no case did zircon gain fluorine due to exchange of lattice-bound substituted OH or other anions with fluorine during the HF partial dissolution phase of the chemical abrasion process. As the OG1, QGNG, and TEMORA-2 zircon samples are known to be compositionally inhomogeneous in trace element composition, spot-to-spot differences dominated the trace element results. Even the 91500 megacrystic zircon pieces exhibited substantial chip-to-chip variation. The light rare earth elements (LREEs) in chemically abraded OG1 and TEMORA-2 were lower than in the untreated samples. Ti concentration and phosphorus saturation ((Y + REE) / P) were generally unchanged in all samples.

On the Mechanism and Quantum Tunneling of the CO2 + OH Anion Reaction in Ice: A Computational Study

On the Mechanism and Quantum Tunneling of the CO₂ + OH Anion Reaction in Ice: A Computational Study

Structure Elucidation of a Novel Polysaccharide Isolated from Euonymus fortunei and Establishing Its Antioxidant and Anticancer Properties.

Euonymusfortunei polysaccharides (EFPs) have not been extensively investigated yet in terms of their extraction and biological activity. The orthogonal experimental design was employed in this study to evaluate the optimum yield of EFPs. A maximum yield of 2.63 ± 0.23% was attained using material-liquid ratios of 60 mL/g, extraction temperature of 80°C, ultrasonic power of 144 W, and extraction time of 75 mins. The polysaccharide content reached 53.47 ± 0.31% when deproteinized thrice. An analysis of monosaccharide composition revealed that these polysaccharides consist of Gal, Glc, Man, Fuc, and Rha with a molar ratio of 7.14 ∶ 23.99 ∶ 6.29 ∶ 6.55 ∶ 1.00, respectively, in EFPs. Subsequently, the in vitro scavenging capacities of 2,2-diphenylpicrylhydrazyl (DPPH) and ·OH and superoxide anion radicals, along with the reducing power of EFPs, were studied. Results revealed that EFPs have higher antioxidant activity, particularly ·OH scavenging, as well as reducing power, as compared to Astragalus polysaccharides (ASPs) and Lycium barbarum polysaccharides (LBPs). The Cell Counting Kit-8 (CCK-8) method was used to evaluate the effects of different concentrations of polysaccharides on SKOV3 cell proliferation, and the results revealed their inhibition at concentrations in the range of 200-800 μg/mL. In addition, findings from flow cytometry further confirmed that EFPs blocked the cell cycle at G0/G1 and S phases and induced SKOV3 cell apoptosis. In a word, EFPs could be exploited and used further based on the experimental results from this study.

Extraction and Biological Activity of Lignanoids from Magnolia officinalis Rehder & E.H.Wilson Residual Waste Biomass Using Deep Eutectic Solvents.

Lignanoids are an active ingredient exerting powerful antioxidant and anti-inflammatory effects in the treatment of many diseases. In order to improve the efficiency of the resource utilization of traditional Chinese medicine waste, Magnolia officinalis Rehder & E.H.Wilson residue (MOR) waste biomass was used as raw material in this study, and a series of deep eutectic solvents (ChUre, ChAce, ChPro, ChCit, ChOxa, ChMal, ChLac, ChLev, ChGly and ChEG) were selected to evaluate the extraction efficiency of lignanoids from MORs. The results showed that the best conditions for lignanoid extraction were a liquid-solid ratio of 40.50 mL/g, an HBD-HBA ratio of 2.06, a water percentage of 29.3%, an extract temperature of 337.65 K, and a time of 107 min. Under these conditions, the maximum lignanoid amount was 39.18 mg/g. In addition, the kinetics of the extraction process were investigated by mathematic modeling. In our antioxidant activity study, high antioxidant activity of the lignanoid extract was shown in scavenging four different types of free radicals (DPPH, ·OH, ABTS, and superoxide anions). At a concentration of 3 mg/mL, the total antioxidant capacity of the lignanoid extract was 1.795 U/mL, which was equal to 0.12 mg/mL of Vc solution. Furthermore, the antibacterial activity study found that the lignanoid extract exhibited good antibacterial effects against six tested pathogens. Among them, Staphylococcus aureus exerted the strongest antibacterial activity. Eventually, the correlation of the lignanoid extract with the biological activity and physicochemical properties of DESs is described using a heatmap, along with the evaluation of the in vitro hypoglycemic, in vitro hypolipidemic, immunomodulatory, and anti-inflammatory activity of the lignanoid extract. These findings can provide a theoretical foundation for the extraction of high-value components from waste biomass by deep eutectic solvents, as well as highlighting its specific significance in natural product development and utilization.

Assessing Permutationally Invariant Polynomial and Symmetric Gradient Domain Machine Learning Potential Energy Surfaces for H3O2.

The singly hydrated hydroxide anion OH-(H2O) is of central importance to a detailed molecular understanding of water; therefore, there is strong motivation to develop a highly accurate potential to describe this anion. While this is a small molecule, it is necessary to have an extensive data set of energies and, if possible, forces to span several important stationary points. Here, we assess two machine-learned potentials, one using the symmetric gradient domain machine learning (sGDML) method and one based on permutationally invariant polynomials (PIPs). These are successors to a PIP potential energy surface (PES) reported in 2004. We describe the details of both fitting methods and then compare the two PESs with respect to precision, properties, and speed of evaluation. While the precision of the potentials is similar, the PIP PES is much faster to evaluate for energies and energies plus gradient than the sGDML one. Diffusion Monte Carlo calculations of the ground vibrational state, using both potentials, produce similar large anharmonic downshift of the zero-point energy compared to the harmonic approximation of the PIP and sGDML potentials. The computational time for these calculations using the sGDML PES is roughly 300 times greater than using the PIP one.

Extending Unique 1D Double-Chains to 2D Layers with Birefringent Gain by Introducing a Hydroxyl Group.

It remains a significant hurdle for discovering birefringent materials in the deep ultraviolet (DUV, λ < 200 nm). It is well-known that the OH anions are recognized for their capability to eliminate the dangling bonds from terminal oxygen atoms, promoting the ultraviolet (UV) cutoff edge blueshift and regulating the crystal structure. Here, two new barium hydroxyborates, Ba3B11O18(OH)3(H2O) (BaBOH) and Na2BaB10O16(OH)2(H2O)2 (NaBaBOH), were designed and synthesized while displaying different dimensions. Remarkably, BaBOH presents novel one-dimensional (1D) [B22O37(OH)6]∞ double-chains formed by a new fundamental building block (FBB)[B11O21(OH)3]. NaBaBOH possesses a 2D [B10O16(OH)2]∞ layer with a less common FBB [B10O19(OH)2]. They enrich the structural diversity of hydroxyborates. Moreover, NaBaBOH exhibits a broad transparent window within the DUV spectral range (<190 nm) and possesses a favorable birefringence of 0.064. Furthermore, detailed summaries and structural comparisons have been implemented for all hydroxyborates containing alkali and alkaline-earth metals. This reveals that the OH group modulation strategy can be appropriately employed for the structural design.

Novel Cerium (IV) Oxide -Ti3C2- titanium dioxide heterostructure photocatalyst for pharmaceutical pollutants removal: Photocatalyst characterization, process optimization and transformation pathways

Tetracycline (TC) is a widely applied antibiotic recognized for its potential negative consequences on human health and ecological balance. In this study, a novel photocatalyst, Cerium (IV) oxide -Ti3C2- titanium dioxide (CeMXT), was synthesized through sonochemical and impregnation techniques, subsequently subjected to comprehensive characterization employing diverse methods including XRD, SEM, TEM, HR-TEM, Raman, XPS, and BET. The optimization of TC degradation was pursued using the Response Surface Methodology (RSM), encompassing variables such as initial TC concentration, irradiation duration, photocatalyst dosage, and pH. The degradation efficacy was investigated through free radical trapping experiments, revealing the pivotal roles of OH and superoxide anion radicals. Remarkable degradation efficiency, reaching 94.70 %, was achieved under specific parameter conditions: 22.19 mg/L TC concentration, 104.13 min irradiation, 0.65 g/L photocatalyst dosage, and pH 4.72. This exceptional performance could be attributed to the elevated generation of oxidant species facilitated by the Z-scheme electron transfer heterojunction. Furthermore, LC-Mass analysis was employed to delineate the intermediates formed during TC photodegradation, culminating in proposing a conceivable degradation pathway. The impressive proficiency of the CeMXT photocatalyst underscores its potential application for effective large-scale treatment of persistent organic pollutants in wastewater treatment facilities. Additionally, comparative analysis with a recently developed photocatalyst highlights its promise as a viable alternative for the remediation of such contaminants in aquatic ecosystems.

Intimate coupling of gC3N4/CdS semiconductor on eco-friendly biocarrier loofah sponge for enhanced detoxification of ciprofloxacin

Ciprofloxacin is one of the antibiotics predominantly used to treat bacterial infections, however excess usage, and release of antibiotic from various sources to the environment can cause severe risks to human health since it was considered as emerging pollutant. This study deals with the intimately coupled photocatalysis and biodegradation (ICPB) of ciprofloxacin using gC3N4/CdS photocatalytic semiconductor and eco-friendly renewable loofah sponge as biocarrier in the ICPB. The photocatalyst gC3N4/CdS was prepared and their synergistic photocatalytic degradation of ciprofloxacin were assessed and the results shows that gC3N4/CdS (20%) exhibit 79% degradation efficiency in 36 h. Further ICPB exhibited enhanced ciprofloxacin degradation 95% at 36 h. The 62.4% and 81.1% of chemical oxygen demand (COD) removal was obtained in the photocatalysis and ICPB respectively. Enhanced degradation of ciprofloxacin and COD removal was due to the synergetic photoelectrons generated from the gC3N4/CdS (20%) transferred to the bacterial communities which intensely mineralize the degradation products produced from the photocatalysis process. Furthermore, production of hydroxyl •OH and superoxide radical anion O2• were identified actively involved in the degradation of ciprofloxacin. The biocarrier loofah sponge provided favourable environment to the bacterial communities for the formation of biofilm and production of extracellular polymeric substances (EPS). Excess quantity of EPS production in the ICPB helps in the prevention of toxicity of photocatalyst to bacterial communities as well as facilitate the extracellular electron transfer process. This work provides a novel path for enhanced degradation of ciprofloxacin using eco-friendly, low cost and renewable biocarrier loofah sponge in the ICPB system.

Hierarchically bread-derived carbon foam decorated with defect engineering in reduced graphene oxide/carbon particle nanocomposites as electrode materials for solid-state supercapacitors

The rational design of defective sites and atomic structure of electrode materials for energy storage devices still remains a challenge. Herein, hierarchically activated carbon foam (ACF) from bread has been developed. The density functional theory (DFT) calculation reveals that oxygen defects can form in the reduced graphene oxide/carbon particle (rGO/CP) derived from graphene oxide frameworks (GOFs) by adding the reducing agent. The synergistic effects of the internal porous architecture of ACF and external interface coupling formed by the defect-rich rGO/CP nanocomposites can provide more electrons to adsorb -OH anions resulting in superior electrochemical energy storage performance. Therefore, the ACF-rGO/large-scale carbon particle (ACF-rGO/LCP) electrodes show ultrahigh specific capacitance (521 F g−1) at a current density of 0.5 A g−1 and outstanding cycling stability with capacitance retention of 96.4 % over 12,000 cycles. Furthermore, the assembled binder-free supercapacitor using KOH/polyvinyl alcohol (PVA) as a gel electrolyte, displays a high energy density of 27.5 W h kg−1 with a power density of 472 W kg−1, and a capacitance retention of 95.2 % after 12,000 cycles. This work provides a novel pathway to prepare high-performance supercapacitors via the treatment of food waste and the recycling of carbohydrate resources.

In-situ hydrogen peroxide formation and persulfate activation over banana peel-derived biochar cathode for electrochemical water treatment in a flow reactor

Electrochemical advanced oxidation processes (EAOPs) are effective for the removal of organic contaminants from groundwater. The choice of an affordable cathode material that can generate reactive oxygen species (ROS) such as hydrogen peroxide (H2O2) and hydroxyl radicals (•OH) will increase practicality and cost effectiveness of EAOPs. Carbon enriched biochar (BC), which is derived from pyrolysis of biomass, has emerged as an inexpensive and environmentally-friendly electrocatalyst for removing contaminants from groundwater. In this study, a banana peel-derived biochar (BP-BC) cathode packed in a stainless steel (SS) mesh was used in a continuous flow reactor to degrade the ibuprofen (IBP), as a model contaminant. The BP-BC cathodes generate H2O2 via a 2-electron oxygen reduction reaction, initiate the H2O2 decomposition to generate •OH, adsorb IBP from contaminated water, and oxidize IBP by formed •OH. Various reaction parameters such as pyrolysis temperature and time, BP mass, current, and flow rate, were optimized to maximize IBP removal. Initial experiments showed that H2O2 generation was limited (∼3.4 mg mL−1), resulting in only ∼ 40% IBP degradation, due to insufficient surface functionalities on the BP-BC surface. The addition of persulfate (PS) into the continuous flow system significantly improves the IBP removal efficiency via PS activation. The in-situ H2O2 formation and PS activation over BP-BC cathode results in concurrent generation of •OH and sulfate anion radicals (SO4•−, a reactive oxidant), respectively, which collectively achieve ∼ 100% IBP degradation. Further experiments with methanol and tertiary butanol as potential scavengers for •OH and SO4•− confirm their combined role in complete IBP degradation.

N-doped porous polymer with protonated ionic liquid sites for efficient conversion of CO2 to cyclic carbonates

A N-doped porous polymer with protonated ionic liquid sites was fabricated by a solvent-free self-assembly synthesis of resorcinol/formaldehyde resin, followed by modification with hydrobromic acid (HBr) to introduce ionic sites. Compared with the parent polymer PIP-HP, polymer PIP-HP-HBr maintains a high specific surface area after ion site construction, and the elevated activity was also acquired under metal/solvent/cocatalyst-free conditions with up to 99% yield of cyclic carbonates. Furthermore, the PIP-HP-HBr as a heterogeneous catalyst can be readily recovered and demonstrate excellent cycling stability. In addition, a plausible catalytic mechanism had been proposed that the high catalytic activity originates from the synergistic effect of hydrogen bond donor –OH and nucleophilic anion Br−.

Selectivity for intercalated ions in MXene toward a high-performance capacitive electrode

The intercalation of foreign ions has been demonstrated to be one of the effective methods to improve the electrochemical performance of Ti3C2Tx MXene. However, whether different intercalated ions have diverse impacts on the MXene structure and electrochemical properties is not well understood. Herein, we comprehensively investigated the structural features and electrochemical performances of a series of ions, including Li+, Na+, K+, Cs+, Zn2+, Mg2+, SO42−, and OH− intercalated MXenes. Different ions are observed to exhibit variations in the intercalation effect because of the differences in their sizes, charge numbers, and chemical features. Among the investigated intercalation agents, CsOH composed of monovalent Cs+ with a large size and strong base anion OH− exhibits a superior intercalation effect, where a large interlayer space accommodating a large amount of free water, a high oxidation state of Ti and a preferred surface with more O-containing functional groups for redox reaction is created, intensifying the pseudocapacitive H+ intercalation. Therefore, CsOH-treated MXene exhibits a significant enhancement in gravimetric capacitance (i.e., approximately 725% of the original) and more than 100% capacitance retention over 20,000 cycles. This paper provides a guideline for the rational design and construction of high-capacitance MXene and MXene-based hybrid electrodes in aqueous electrolytes.

Insights into the Role of Electrolyte Ionophore on Electrochemical Reduction of CO2

Electrochemical reduction of carbon dioxide (CO2) to value-added chemicals and fuels offers a sustainable route to utilize CO2 by exploiting renewable energy source. The electrolyte plays a significant role by taking advantage of the interaction between electrocatalytic surface and electrolyte. In this work, we present a CO2 conversion flow cell with an external compartment for a reference electrode (AgCl/Ag) to investigate the effect of alkaline electrolyte composition on the direct conversion of CO2 to fuels and commodity chemicals under ambient conditions. In this flow cell, a catalytic Ag-based gas diffusion electrode (GDE) was employed for CO2 reduction reaction, while an anode electrode was prepared with a RuO2 catalytic GDE. The gaseous products generated from the cell were analyzed with a Gas Chromatography (GC), while the liquid products were analyzed with Nuclear Magnetic Resonance Spectroscopy (NMR). Electrolytes with various cations (Li+, Na+, K+) and anions (OH-, HCO3 -, CO3 2-) were investigated. With a KOH electrolyte (combination of the cation K+ and anion OH-), high faradaic efficiency (~ 97%) was achieved at -1.115 V vs SHE toward the formation of syngas (CO + H2) and ~ 60% faradaic efficiency was obtained toward the product of ethanol. The overall energy conversion efficiency could be up to ~ 45%. In consideration of faradaic efficiency, energy conversion efficiency, and the production of CO and ethanol, the preferable option of anions followed the order of OH- > HCO3 - > CO3 2-, while the option for cations was in the order of K+ > Na+ > Li+.

Phytochemical Analysis and Evaluation of Antimicrobial, Antioxidant, Anti-inflammatory and Antiangiogenic activities of Methanol extract of Urochloa ramosa

Urochloa ramosa is a plant of the wet, seasonally dry and semi-arid tropics. It is also known as Bracharia ramosa or Brown top millet. Qualitative analysis of phytochemicals in methanol extracts were performed by standard methods. Partially purified phenolics from the methanol extract of leaf sample was subjected for different biological activities. In vitro antimicrobial activity was executed on Bacillus subtilis, Staphylococcus epidermidis and Staphylococcus aureus (Gram positive) and Proteus, Salmonella and Escherichia coli (Gram negative) bacteria and Candida albicans (yeast type fungi). Minimum inhibitory concentration was calculated by Resazurin method. In-vitro antioxidant assay was conducted by DPPH radical, NO. radical, superoxide anion radical scavenging assays and OH radical scavenging activity by DNA protection assay using BHT as the reference compound. IC50 value of methanol extract for each of these assays was calculated. Albumin denaturation assay, antiproteinase activity and membrane stabilization were performed to test the anti-inflammatory potential at various concentrations of methanol extract of U.ramosa. In vivo anti-angiogenesis activity was carried out by shell less chick chorioallantoic membrane assay. In the antimicrobial activity we found that Staphylococcus aureus showed considerable susceptiblity with the MIC value of 145μg and Staphylococcus epidermidis is the most resistant with the MIC value of 378μg/ml. IC50 of 10.10µg/ml, IC50 of 17.32µg/ml and IC50 of 25.12µg/ml demonstrated antioxidant activities of methanol extract of U. ramosa by scavenging DPPH, NO. and superoxide anion radicals respectively. At 100µg/ml concentration, methanol extract significantly protected DNA against the effect of hydroxyl radicals. Protein denaturation was protected between concentrations 100-500µg/ml of methanol extract, maximum proteinase inhibitory activity was significantly found at 500µg/ml concentration and even haemolysis (heat and hypotonicity induced) was prevented considerably at 500µg/ml of methanol extract. Inhibition of proliferation of capillaries was observed in chorioallantoic membrane assay proving methanol extract’s antiangiogenic property. The leaves of Urochloa ramosa are basically enriched with natural phenolics with multitudinous biological potencies that can represent a promising class as bioactive molecules.

MgO coated magnetic Fe3O4@SiO2 nanoparticles with fast and efficient phosphorus removal performance and excellent pH stability

A regenerable MgO-coated magnetic Fe3O4@SiO2 (FSM) composite effectively avoided the agglomeration of nano-MgO, which was resoundingly used for efficient and rapid phosphorus removal from aqueous solutions. Based on an initial screening of synthesized FSM with different Mg/citric acid molar ratios in terms of phosphorus adsorption capacity, an FSM composite with a Mg-citric acid molar ratio of 1:1 (FSM-1:1) was determined as the optimal choice. Scanning electron microscope (SEM), Fourier transform infrared (FTIR) and X-ray diffraction (XRD) showed that the prepared Fe3O4 was triumphantly loaded and the nano-MgO nanoparticles were evenly distributed on the surface of magnetic mesoporous silica. N2 adsorption-desorption experiments manifested that FSM-1:1 had a large specific surface area of 124.3 m2/g and the pore size distribution calculated based on the BJH model was centered at 9.36 nm. Furthermore, FSM-1:1 not only exhibited fast adsorption kinetics (60 min) but also had a high maximum theoretical adsorption capacity of 223.6 mg P/g, which was superior to all the other Mg-based adsorbents. Remarkably, due to the coating of MgO, FSM-1:1 exhibited ultra-high stability in the pH range of 3–11, a wider range than many other Mg-modified sorbents. Our adsorbents also showed excellent selectivity for phosphate anions even in the presence of various coexisting anions (e. g. NO3−, Cl− and SO42−) with varying ionic strengths (0.01 and 0.1 M), good recyclability, the removal rate of phosphate still reached 89.0% after three cycles. Electrostatic attraction, Lewis acid-base interaction and the ligand exchange between Mg–OH and phosphate anions were responsible for the phosphate adsorption mechanisms.

Double‐Modification Oriented Design of a Deep‐UV Birefringent Crystal Functionalized by [B12O16F4(OH)4] Clusters

Polarization modulation of deep-UV light is of great significance to the current technologies, and to this end, birefringent crystal has emerged as an invaluable material as it allows for the effective light modulation. Herein, double-modification strategy driven by F and OH anions that makes double effects towards the critical property enhancement of deep-UV birefringent crystals is proposed. This leads to the discovery of a new hydroxyborate (NH 4 ) 4 [B 12 O 16 F 4 (OH) 4 ] with unprecedented giant cluster as a deep-UV birefringent crystal with large birefringence (Δ n exp. = 0.12@546 nm). Such a birefringence sets a record among inorganic hydroxyborates with experimentally measured birefringence. The [B 12 O 16 F 4 (OH) 4 ] cluster in near-plane arrangement is enabled by the hydrogen-bonding interactions; and it is theoretically confirmed to be optical-active for large birefringence and band gap, in which the π-conjugated modules, [BO 3 ] and [BO 2 (OH)], are the main sources of large optical anisotropy.

Double‐Modification Oriented Design of a Deep‐UV Birefringent Crystal Functionalized by [B12O16F4(OH)4] Clusters

AbstractPolarization modulation of deep‐UV light is of significance to current technologies, and to this end, the birefringent crystal has emerged as an invaluable material as it allows for effective light modulation. Herein, a double‐modification strategy driven by F and OH anions that makes double effects towards the critical property enhancement of deep‐UV birefringent crystals is proposed. This leads to a new hydroxyborate (NH4)4[B12O16F4(OH)4] with giant cluster as a deep‐UV birefringent crystal with large birefringence (Δnexp.=0.12@546.1 nm). This birefringence is a record among inorganic hydroxyborates with experimentally measured birefringence. Structural analysis shows that the near‐plane arrangement of [B12O16F4(OH)4] cluster is responsible for the large optical anisotropy. Theoretical calculations indicate that its π‐conjugated [BO3] and [BO2OH] units are the main source of this large optical anisotropy.

Adsorption and electric field assisted activation of ammonia -borane over BC3 sheet: A computational study

Using first-principles calculation within density functional theory (DFT), we studied the adsorption behavior of ammonia-borane (H3BNH3, AB) molecule on BC3 sheet in four different solvents. We concentrated on the activation of AB adsorbed on BC3 sheet in aqueous solutions of AB with and without an external electric field (E-field). The results show that the BC3 sheet has a better activation effect on the B–H bond of AB in alkaline aqueous solutions than in a neutral aqueous solution. Compared with the metal cation (Na+ or K+), anion OH− is more conducive to the activation of the B–H bond, which is more obvious in the case of an external E-field. Under the external E-field (0.004 a.u.), the B–H bond is elongated by about 12% compared with that of AB molecule in a free state, even if the metal cations are considered, the B–H bond is still elongated by about 10.6%. This study offers a new research method for the release of H atom in AB molecule facilitating H2 production.

Ability ofB12N12fullerene like nano‐cage for sensing and improving the antioxidant activity of juglone and its derivative: Density functional theory investigation

AbstractTheoretical chemistry calculations were used to investigate the ability of the B12N12fullerene like nano‐cage for sensing juglone (Jug) and one of its derivative (JugOH) in gas phase, pentyl ethanoate (PE) and water. Results obtained at DFT/M05‐2X‐D3/6‐311+G(d,p) level of theory showed that B12N12is able to adsorbed Jug preferentially by binding to one of the O‐atom of its carbonyl groups. Based on natural bond orbital analysis, a charge transfer from the oxygen atoms of Jug and JugOH to the anti‐bonding orbital of B was revealed. Quantum theory of atoms in molecule analysis showed that the B12N12Jug and B12N12JugOH complexes are stabilized by a partially covalent BO bond in addition to attractive non covalent interactions. The ability ofJug,JugOHas well as their complexesAandAOHto scavenge HO●radical has been investigated via the usual hydrogen atom transfer mechanism in the three media of study previously stated. Theoretical evaluation of pH effect on this radical scavenging activity revealed that in water, the anionic forms ofJugOH(86%) andAOH(96%) are dominant and mainly transfer their remaining H‐atom to HO●via a spontaneously reaction, the complex presenting the lowest Gibbs free energy. These results provide fundamental knowledge for the development of new antioxidant delivery careers.