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Green hydrogen is a crucial element in the hydrogen value chain, encompassing hydrogen production, transportation, storage, and application. The production of green hydrogen via NaBH 4 hydrolysis (SBH) entails a high cost. However, the fast kinetics of this process with a catalyst compensate for the substantial cost, especially in specific applications, such as local or intermittent use. Silver is known for its excellent catalytic properties. Its high catalytic activity is a key factor in achieving efficient hydrogen generation from (SBH). In this study, a nanocomposite catalyst composed of silver nanoparticles (AgNPs), CoFe 2 O 4 , and carbon nanotubes (CNT) was investigated to demonstrate an effective catalyst design approach to achieve enhanced hydrogen generation performance. The H 2 production rate in the presence of Ag-based/CoFe 2 O 4 –CNT was 320 mL min−1 g−1, and the apparent activation energy was 14.7 kJ mol−1, superior to that of Ag-based catalysts reported in the literature. Analyses of the observed outcomes revealed that the CNT was decorated with well-dispersed AgNPs and CoFe 2 O 4 nanoparticles. The synergistic effects of AgNPs, CoFe 2 O 4 , and CNT were demonstrated by analyzing the kinetic behaviour of each component based on systematic comparisons. Furthermore, the paramagnetic property of CoFe 2 O 4 enables harvesting of the catalyst using an external magnetic field, and it was verified that the reactivity of the collected catalyst was maintained throughout seven successive cycles. The outstanding catalytic performance of Ag/CoFe 2 O 4 – CNT should be attributed to the uniform dispersion of nanoparticles on the CNT surface. Furthermore, our key approach for developing efficient Ag-based carbon advanced catalysts for SBH in the future is to ensure their suitability for industrial applications. Graphical illustration for the hydrogen production by hydrolysis process. [Display omitted] • A magnetic Ag/CoFe 2 O 4 -carbon nanotube nanocomposite was designed and synthesized. • Highly dispersed CoFe 2 O 4 and AgNPs are evenly embedded on the CNT. • Reaction kinetics followed during hydrogen production under different experimental conditions have been investigated. • The ACC catalyst demonstrated high activity, good recyclability, and low activation energy. [ABSTRACT FROM AUTHOR]

The semi‐hydrogenation of terminal alkynes is achieved with sodium borohydride (NaBH4) as the reductant and palladium nanowires (PdNWs) as the catalysts under ambient conditions. The reaction proceeds smoothly in the presence of only 0.32 mol % of PdNWs, giving the hydrogenated products with up to 98 % overall yields, in which 97 % are semi‐hydrogenated products. Under the optimal reaction conditions, both aromatic and aliphatic terminal alkynes have been successfully converted to the corresponding olefins with high efficiency and good selectivity. This method promotes the hydrogenation of terminal alkynes under mild conditions and opens up a window for the application of metal nanowires in organic syntheses. [ABSTRACT FROM AUTHOR]

HPSB (Hydrolysis Product of Sodium Borohydride) hydrogen storage material is a kind of porous lamellar structural material developed by our research group. Due to the special structure of this material, it can absorb hydrogen at room temperature, hydrogen absorption pressure is 2–4 MPa, and hydrogen absorption time is 2–5 min. The main preparation method used in the experiment is hydrolysis. The main raw material is sodium borohydride, and the reaction temperature is 30 °C. In this experiment, in order to improve the hydrogen storage performance of HPSB hydrogen storage material, Co–B and Sm 2 O 3 were introduced as catalysts during the preparation of HPSB. The results show that the amount of Sm 2 O 3 and the ratio of Sm 2 O 3 to Co–B have obvious influence on the hydrogen storage performance of HPSB. In addition, according to the results of SEM analysis, the amount of Sm 2 O 3 and the ratio of Sm 2 O 3 to Co–B also have obvious effects on the microstructure of HPSB hydrogen storage materials. The sample with a doping amount of 4 wt% and a ratio of Sm 2 O 3 to Co–B of 4:6 can release 2.17 wt% H 2. • The catalyst Co–B/Sm 2 O 3 can improve the hydrogen storage performance of HPSB. • Co–B/Sm 2 O 3 doping 4 wt% and ratio 4:6 shows the best dehydrogenation performance. • The maximum total dehydrogenation amount of the Co–B/Sm 2 O 3 doped sample is 2.17 wt%. [ABSTRACT FROM AUTHOR]

The selection of an appropriate preparation method is crucial to enhance catalytic performance and optimize the resources used in catalyst synthesis. Achieving improvements in conversion rates, desired product yields are essential for increasing interest and competitiveness in the industrial sector. This study aims to analyze the influence of the preparation method of Rh(1%)-Sn(4%)/γ-Al2O3 catalysts on the selective hydrogenation of oleic acid to oleyl alcohol. Results from temperature-programmed reduction (TPR), cyclohexane dehydrogenation (DHC), and X-ray photoelectron spectroscopy (XPS) clearly demonstrate that incorporating sodium borohydride in the preparation process results in a stronger interaction between Rh and Sn. The degree of interaction between Rh and Sn is significantly influenced by the catalyst preparation and activation method, with a strong interaction promoting selectivity towards the formation of oleyl alcohol. [ABSTRACT FROM AUTHOR]

The construction of efficient and durable multifunctional electrodes for industrial‐scale hydrogen production presents a main challenge. Herein, molybdenum‐modulated phosphorus‐based catalytic electrodes (Mo‐NiP@NF) are prepared via mild electroless plating. Heteroatoms doping or heterostructures construction can reconfigure the intrinsic electronic structure of the pre‐catalyst and optimizes the key intermediates adsorption. Moreover, the (hypo/meta‐)phosphite anions (POxδ−) and molybdate ions (MoOxδ−) on the electrode surface of Mo‐NiP@NF afford resistance to chloride (Cl−) corrosion. Mo‐NiP@NF exhibits ultralow overpotentials of 278/550 and 282/590 mV at 1 A cm−2 during the hydrogen/oxygen evolution reaction (HER/OER) in alkaline simulated and real seawater, respectively, whereas catalytic overall seawater splitting (OWS) reach 1 A cm−2 at 1.96 and 1.97 Vcell. Remarkably, Mo‐NiP@NF maintains stable operation for 1500 h in OWS. The scalability of Mo‐NiP@NF allowing the assembly of proton exchange membrane (PEM) electrolyzer powered by photovoltaic energy, simulating a portable hydrogen‐oxygen respirator provides an oxygen/hydrogen flows of 160/320 mL min−1. Expanding further, the trace ruthenium‐loaded Mo‐NiP@NF catalyst sodium borohydride (NaBH4) hydrolysis achieving a hydrogen generation rate (HGR) of 11049.2 mL min−1 g−1. This work provides strategic innovations and optimization solutions for the economical and mild construction of multi‐scenario durable green energy conversion materials at industrial‐scale application. [ABSTRACT FROM AUTHOR]

A facile and practical one‐pot synthesis of hydrobenzoin has been developed from the readily available aromatic aldehydes, under NHC catalysis. Basically, the present research elucidates a novel, sustainable approach for the synthesis of hydrobenzoin, capitalizing on the catalytic prowess of N‐heterocyclic carbene (NHC) and utilizing sodium borohydride (NaBH4) as an effective reducing partner in this one‐pot conversion. By harnessing the unique reactivity of NHCs, this methodology enables the efficient formation of C−C bonds, leading to the streamlined synthesis of hydrobenzoin with high yields while tolerating various functional groups. Furthermore, this catalytic system offers notable advantages in terms of atom economy, mild reaction conditions, and operational simplicity, making it a promising strategy for sustainable chemical synthesis. The detailed mechanistic insights provided herein shed light on the underlying catalytic pathways, facilitating a deeper understanding of the reaction mechanism. Overall, this study underscores the significant potential of NHC catalysis as a versatile tool for the sustainable synthesis of valuable organic compounds, thereby contributing to the advancement of green chemistry principles and the pursuit of environmentally benign chemical processes. [ABSTRACT FROM AUTHOR]

In this study, we report that pectin‐supported ruthenium nanoparticles (pectin@Ru0) can be easily prepared at room temperature by a simple and effective method and that they exhibit outstanding catalytic activity in the hydrolysis of sodium borohydride (NaBH4). The structure, oxidation state, morphology, and thermal studies were analyzed using XRD, XPS, SEM, TEM and TGA analysis. The kinetic performance of pectin@Ru0 biocatalyst was evaluated depending on ruthenium loading, NaBH4 concentration, NaOH concentration, temperature, reusability and storage. The pectin@Ru0 biocatalyst containing 2 wt.% Ru0 metal catalyzed the hydrolysis of 50 mM NaBH4+1 wt.% NaOH with 100 % yield. The activation energy (Ea) and the TOF values of the reaction was estimated as 54.7 kJ mol−1 and 53.1 mol H2 (mol Ru0 min) −1 at 30 °C and this is consistent with other previously reported catalysts, making it a remarkable result in comparison. Reusability and catalytic life studies reported that pectin@Ru0 biocatalyst is also highly active and relatively long‐lived catalyst in the hydrolysis of NaBH4 in a slightly basic solution. [ABSTRACT FROM AUTHOR]

The present work demonstrates a low-cost, single-step route for synthesizing ZnO, CuO, and ZnO–CuO nanomaterials using oxalic acid as a precipitating agent, avoiding using other surfactants. The current research also demonstrates the chemical reduction method for incorporating Ag nanoparticles onto the surface of the synthesized metal oxide nanostructures using sodium borohydride as the reductant. X-ray diffraction studies reveal the phase purity and crystallinity of the nanoparticles, while X-ray Photoelectron Spectroscopy characterizes the chemical states of surface elements. UV–vis spectra of the samples disclose the modifications shaped by Ag nanoparticles in the absorption characteristics and energy band gap of ZnO, CuO, and ZnO–CuO nanomaterials. The catalytic potentials of the synthesized materials are tested by monitoring degradation reactions of hazardous organic pollutants, including methylene blue and methyl orange, within a few minutes. The significant finding of the present study emphasizes the incorporation of Ag nanoparticles to ZnO–CuO nanocomposite and the use of sodium borohydride in photocatalysis effectively to enhance the rates of degradation of pollutant dyes without the use of intense radiation or unique lamps by initiating a three-stage electron transfer mechanism. [ABSTRACT FROM AUTHOR]

Hydrazine and its derivatives have served as a conventional bipropellant fuel for several decades. However, their extremely acute toxicity and carcinogenicity, high volatility, and environmental impact have attracted significant attention. In order to synthesize green bipropellant fuels with high density, high specific impulse, and good thermal stability, three novel N -alkyl-1,2,4-triazole–borane complexes were successfully synthesized by reacting alkylated 1,2,4-triazole coordinated with sodium borohydride in the presence of ammonium sulfate. During the droplet test with white fuming nitric acid, there was a relatively short ignition delay time of 98 ms. Additionally, these hypergolic fuels possessed a high density exceeding 1.10 g cm–3 , and the specific impulse is ranging from 187 to 199 s, and the highest decomposition temperature reaches 153.4 °C. These results demonstrate their great potential as hypergolic fuels or hypergolic ionic liquid additives in the field of hypergolic materials. [ABSTRACT FROM AUTHOR]

Development of heterogeneous catalyst is significant key for achieving high performance of NaBH 4 hydrolysis to produce hydrogen. The stability of sodium borohydride in the presence of suitable catalyst is the efficient method to generate hydrogen. In this work, styrene-imid PIILP, polymer 1 decorated styrene, imidazolium ionic liquid, and cross-coupling is successfully synthesised by AIBN initiated radical polymerisation, then precipitation with 3,3′,3″phosphinetriyltribenzene sulfonate with ratio (1:0.3) to isolate the first styrene-imid- sulphonated PIILP, polymer 2. RuNP@styrene-imid-sulphonated PIILP, RuNPs catalyst 3 was synthesised by impregnation with RuCl 3 , then reduction by NaBH 4. Moreover, several analytical techniques such as, 31P, 1H, 13C solid-state NMR, CHN, IR, XPS, TEM, TGA-DTA, and SEM were examined to explore the obtained catalyst 3. The hydrogen generation from NaBH 4 utilizing catalyst 3 was exhibited the catalytic behaviour studying several parameters such as, temperature, catalytic loading, and NaBH 4 concentrations this work was deducted the activation energy (30.32 kJmol-1), and the turnover frequency (TOF) reached up 134.9, 112.77, and 98.38 moleH 2.mol cat −1.min−1 at 40, 35 and 30 °C. The effectiveness of Ruthenium nanoparticle catalyst 3 for the hydrolysis reaction of NaBH 4 was examined in H 2 O and D 2 O resulting kinetic isotope effect (KIE) k H /k D = 3. In addition, RuNPs demonstrated a promising efficient for reuse catalyst 3 after five cycles for the catalytic hydrolysis. [Display omitted] • RuNPs was synthesised and characterised by 31P and 13C Solid-State NMR, CHN, XPS, TEM, SEM, TGA and FT-IR. • A TOF 134.9 mole H2.mol cat −1.min−1 for RuNPs@styrene-imid-sulphonated PIILP was achieved. • E a of 30.32 for RuNPs@styrene-imid-sulphonated PIILP were achieved. • RuNPs demonstrated a promising efficiency for reuse RuNPs after five cycles for the catalytic hydrolysis. [ABSTRACT FROM AUTHOR]

In this study, hydrogen production through the hydrolysis, ethanolysis, and methanolysis reactions of NaBH4 using adipic acid as a catalyst was investigated for the first time. Adipic acid solutions were prepared with methanol and ethanol at concentrations of 0.1, 0.2, 0.3, 0.4, and 0.5 M. In these reactions, NaBH4-MR (methanolysis) and NaBH4-ER (ethanolysis) reactions were carried out at 30, 40, and 50 °C with NaBH4 concentrations of 1.25%, 2.5%, and 5%. Hydrolysis reactions (NaBH4-HR) were conducted at 0.1 M under the same conditions. In the ethanolysis and methanolysis reactions at 30 °C, total hydrogen conversion was achieved at 0.3 M, 0.4 M, and 0.5 M. However, in the hydrolysis reactions, total hydrogen production was only obtained at 50 °C. It was observed that in the NaBH4-MR and NaBH4-ER reactions, total hydrogen conversion could be achieved within 4–5 s. The utilization of adipic acid as a catalyst for hydrogen production from NaBH4 through ethanolysis and methanolysis reactions is proposed as a highly efficient and fast method, characterized by impressive conversion rates. [ABSTRACT FROM AUTHOR]

The carbon‐carbon bond in three‐membered ring of 2,3‐diaryl aziridines was reductively cleaved to give the corresponding dibenzylamine derivatives by electrocyclic ring opening of N‐Li or N‐Na aziridines followed by reduction of the 2‐azaallyl anion formed with sodium borohydride in ethanol. Hydrocyanation of the 2‐azaallyl anion with trimethylsilyl cyanide gave a secondary amine bearing a cyano group at the benzylic position. The effects of substituents on the electrocyclic ring opening of N‐Li aziridines were also clarified. [ABSTRACT FROM AUTHOR]

Among hydrogen storage chemicals for proton exchange membrane fuel cells (PEMFCs), sodium borohydride stands out for yielding exceptionally pure hydrogen. This study synthesized cobalt-molybdenum catalysts supported on g-C 3 N 4 using an ultrasonic-assisted impregnation method. Various CoMo/g-C 3 N 4 catalysts with different CoMo mass ratios were created, all showing high hydrogen production and complete NaBH 4 conversion under mild conditions. Catalytic activity depends on the cobalt-molybdenum mass ratio, with optimal performance at a 1:1 ratio (w/w), maintaining up to 83% activity over 5 cycles. The effect of operating conditions on hydrogen release was explored, resulting in the rate law: rH 2 = 1.708 × 10-3 [NaBH 4 ]1.25 [Catalyst dosage]1.39 [NaOH]0.44 at 298 K, with a low activation energy of 22.9 kJ mol−1. Molybdenum's promoting effect prevented significant deactivation of the cobalt catalyst, ensuring complete NaBH 4 conversion to H 2 and good stability over multiple cycles. [Display omitted] • CoMo/g-C 3 N 4 synthesized cost-effectively via ultrasonic-assisted impregnation. • 1:1 CoMo/g-C 3 N 4 exhibited high HGR and complete NaBH 4 conversion at mild conditions. • NaBH 4 hydrolysis using CoMo/g-C 3 N 4 presented low energy activation (22.9 kJ mol−1). • 1:1 CoMo/g-C 3 N 4 maintains selectivity for 8 cycles and 83% of activity for 5 cycles. • Molybdenum identified as a promoter reduces cobalt catalyst deactivation. [ABSTRACT FROM AUTHOR]

Sodium borohydride (NaBH 4) hydrolysis is considered as a promising hydrogen production strategy. The key to accelerating NaBH 4 hydrolysis is the development of efficient catalysts. Metal-modified cobalt boride has demonstrated superior catalytic activity for NaBH 4 hydrolysis compared to pure cobalt boride. However, the relationship between the high activity of metal-modified cobalt boride and the modifying metal has not been summarized. In this work, through extensive literature research, the mechanisms of metal modification on the catalytic activity improvement of metal-modified cobalt boride were clarified, the reaction mechanisms of NaBH 4 hydrolysis catalyzed by cobalt boride and metal-modified cobalt boride were compared and analyzed, the challenges metal-modified cobalt boride may encounter in the future study of NaBH 4 hydrolysis were discussed, and our recommendations were provided. This work can provide an important theoretical basis for the design and development of efficient and robust catalysts, as well as for the advancement of hydrogen production technology. • Metal-modified cobalt boride (Co-M-B) for NaBH 4 hydrolysis was overall reviewed. • The mechanism of catalytic activity enhancement of Co-M-B was clarified. • Challenges that Co-M-B may encounter in future development were proposed. [ABSTRACT FROM AUTHOR]

This study focuses on establishing the kinetic parameters for the catalytic dehydrogenation process of NaBH4. This reaction occurs in the presence of a co-catalyst derived from metallic sources of Co and Ni. For this purpose, a heterogeneous catalyst was synthesized using metal-organic frameworks (MOFs) as the supporting material. CoF2 and NiF2 for cobalt and nickel were the active metal sources, respectively. Metal organic framework (MOF), MIL-101 (Cr), was chosen because it has a larger specific surface area than other materials (2504 m2g-1). The reaction rate constants and rate order were calculated via the differential method. As a result, zero-order kinetics was proved by using the experimental data. After that, the activation energy was calculated as 51.06 kJ/mol through the slope of the graph of lnk versus 1/T for the hydrolysis reaction. The dehydrogenation index of NaBH4 was calculated as 2150 mL H2/g NaBH4 according to the amount of NaBH4 in the aqueous solution. There is no doubt MOFs are promising novel materials synthesized for various aims. Here, we tried to indicate its different usage areas in catalytic reactions. [ABSTRACT FROM AUTHOR]

Green synthesis of nanomaterials is advancing due to their ease of synthesis, cheapness, nontoxicity, and renewability. An environmentally friendly biogenic method has been developed for the green synthesis of nickel oxide nanoparticles (NiO NPs) using phytochemical-rich bioextract. They are rich in bioextract phenolics, flavonoids, and berberine. These phytochemicals successfully reduce and stabilize NiNO3 into NiO NPs. In this study, NiO NPs were synthesized by the green synthesis method from Lupinus Albus. Characterization of NiO NPs was carried out by TEM, XRD, SEM, UV, XRF, BET, and EDX analyses. According to XRD analysis, TEM results also support this, where the NiO NPs particle size diameter is 5 nm. It was determined by the Tauc equation that the band energy gap of NiO NPs is 1.69 eV. It was determined that the BET surface area of NiO NPs was 49.6 m2/g. NiO nanoparticles synthesized from Lupinus Albus extract by the green synthesis method were used as catalysts in the photocatalytic reduction of methylene blue with NaBH4. In the photocatalytic reduction of methylene blue with NaBH4, it was determined that there was no color change in 48 h without a catalyst, and in the presence of NiO nanoparticle catalyst, methylene blue was reduced by 97% in 8 min. The kinetics of the photocatalytic reduction of methylene blue with NaBH4 is a pseudo-first-order kinetic model and the kinetic rate constant is determined as 0.66 min−1, indicating that the catalytic effect of NiO NPs is very high at this value. NiO NPs were used five times in the photocatalytic reduction of methylene blue with NaBH4 and it was determined that the reduction of methylene blue was over 90% in each use. NOVELTY STATEMENT: NiO nanoparticles were synthesized from Lupinus Albus extract by green synthesis, which is an easily applied, cost-effective, and environmentally friendly method. The synthesized NiO nanoparticles were characterized using various characterization techniques. NiO nanoparticles have a high catalytic effect in the photocatalytic reduction of methylene blue with NaBH4. Photocatalytic reduction of methylene blue with uncatalyzed NaBH4 could not be achieved, and 97% reduction of methylene blue was completed in 8 min in the presence of NiO nanoparticle catalyst. [ABSTRACT FROM AUTHOR]

Platinum and ruthenium nanoparticles stabilised by an amine modified polymer immobilised ionic liquid (MNP@NH2-PEGPIILS, M = Pt, Ru) catalyse the hydrolytic liberation of hydrogen from dimethylamine borane (DMAB), ammonia borane (AB) and NaBH4 under mild conditions. While RuNP@NH2-PEGPIILS and PtNP@NH2-PEGPIILS catalyse the hydrolytic evolution of hydrogen from NaBH4 with comparable initial TOFs of 6,250 molesH2.molcat−1.h−1 and 5,900 molesH2.molcat−1.h−1, respectively, based on the total metal content, RuNP@NH2-PEGPIILS is a markedly more efficient catalyst for the dehydrogenation of DMAB and AB than its platinum counterpart, as RuNP@NH2-PEGPIILS gave initial TOFs of 8,300 molesH2.molcat−1.h−1 and 21,200 molesH2.molcat−1.h−1, respectively, compared with 3,050 molesH2.molcat−1.h−1 and 8,500 molesH2.molcat−1.h−1, respectively, for PtNP@NH2-PEGPIILS. Gratifyingly, for each substrate tested RuNP@NH2-PEGPIILS and PtNP@NH2-PEGPIILS were markedly more active than commercial 5wt % Ru/C and 5wt% Pt/C, respectively. The apparent activation energies of 55.7 kJ mol−1 and 27.9 kJ mol−1 for the catalytic hydrolysis of DMAB and AB, respectively, with RuNP@NH2-PEGPIILS are significantly lower than the respective activation energies of 74.6 kJ mol−1 and 35.7 kJ mol−1 for its platinum counterpart, commensurate with the markedly higher initial rates obtained with the RuNPs. In comparison, the apparent activation energies of 44.1 kJ mol−1 and 46.5 kJ mol−1, for the hydrolysis NaBH4 reflect the similar initial TOFs obtained for both catalysts. The difference in apparent activation energies for the hydrolysis of DMAB compared with AB also reflect the higher rates of hydrolysis for the latter. Stability and reuse studies revealed that RuNP@NH2-PEGPIILS recycled efficiently as high conversions for the hydrolysis of DMAB were maintained across five runs with the catalyst retaining 97% of its activity. [ABSTRACT FROM AUTHOR]

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Complex hydrides, such as sodium borohydride (NaBH4), are attractive materials for hydrogen storage because of their high hydrogen capacity. However, practical application of these materials is limited because of their unfavorable hydrogen thermodynamics and poor kinetics. Herein, it is demonstrated that the inclusion of BF4− in NaBH4 results in remarkable Na+ conductivity of 1.5 × 10−3 S cm−1, which is 10 000 times higher compared to pure NaBH4 (7.0 × 10−8 S cm−1) at 115 °C. The ionic conductivity is also comparable to values reported for some of the best borohydride‐based conductors reported to date. More remarkably, this improvement of ionic conductivity is found to be correlated to lower hydrogen release temperatures for BF4−‐modified NaBH4 releasing hydrogen at a temperature of 200 °C instead of 510 °C in the case of pristine NaBH4. Nudged elastic band calculations based on density functional theory reveal that partial substitution of the [BH4]− groups in NaBH4 by BF4− may lead to the formation of distortions within the NaBH4 crystal lattice with favorable channels for Na+ mobility enabling the release of hydrogen at low temperatures. [ABSTRACT FROM AUTHOR]

(1) Reduced glutathione (GSH) is considered the first line of antioxidant defense. During oxidative stress, it is oxidized to glutathione disulphide (GSSG). (2) A simple and quick spectrophotometric method based on sodium borohydride (NaBH4) as a reductant to measure the total and reduced GSH in porcine saliva was analytically validated and evaluated in two situations in this species: (a) in a physiological situation, involving sows during the late lactation and post-weaning periods, and (b) in a situation of sepsis in pigs experimentally induced by LPS administration. (3) The results of the analytical validation showed that the assay was precise and accurate in the porcine saliva samples. Higher total GSH and GSSG and lower reduced GSH were observed in the saliva of sows during the post-weaning period, as well as in pigs with experimentally induced sepsis. (4) In conclusion, the validated assay showed adequate analytical results and could be used to evaluate the GSH system of porcine saliva, as demonstrated during the clinical performance. [ABSTRACT FROM AUTHOR]

The synthesis of small heterocycles under neat mechanochemical conditions is of great interest in the field of drug design because most of the commercially available drugs contain at least one heterocyclic unit. The sodium borohydride (NaBH4) promoted reductive cyclization to fused dihydrofuran under grinding technique is one of the compendium additions for the clean future. The development of chemoselective reduction under silica‐gel supported conditions represents significant progress in organic synthesis, offering a versatile and efficient method for selective reduction of specific functional groups within complex molecules. Synthesis of isoindole derivatives from the chemoselective reduce product via a sustainable short synthetic pathway is another significant process of our newly developed protocol. Finally, antileishmanial investigations of our synthesized compounds establish a soft bridge between biology and chemistry. [ABSTRACT FROM AUTHOR]

For the first time, oxide (TiO2, CeO2, ZnO, Al2O3) supported Cu catalysts, prepared by the aqueous reduction method using sodium borohydride, were employed for the acceptorless dehydrogenation of 2‐octanol and various C4–C8 polyols. The method used to prepare the catalysts enabled the formation of small Cu particles in the range of 14–36 nm, depending on the point of the zero charge of the support. We showed that the conversion increased with Cu surface area, where Cu/TiO2 led to the highest conversion of 2‐octanol (>99.9%). The selectivity depends on the support and conversion. Up to 80% conversion, the selectivity to 2‐octanone was between 83% and 90% when using Cu/TiO2. In this study, we also report for the first time the acceptorless dehydrogenation of 1,3‐butanediol, 2,3‐butanediol, 1,2‐pentanediol, and 1,5‐pentanediol in liquid phase. While metal active sites promoted the dehydrogenation reaction, the presence of acidic and basic sites favored the formation of by‐products, mainly resulting from dehydration reactions, pinacol rearrangements, and aldol and retro‐aldol condensations. In addition to value‐added chemicals, all the reactions also released molecular hydrogen. [ABSTRACT FROM AUTHOR]

Hydrogen (H2) storage is one of the most problematic issues regarding the widespread use of hydrogen, and solid-state hydrogen storage materials are promising in this regard. Hydrogen storage by sodium borohydride (NaBH4) takes attention with its advantages and idiosyncratic properties. In this study, potentials and challenges of sodium borohydride are evaluated considering storage conditions, safety, hydrogen purity, storage capacity, efficiency, cost, and the maturity. Moreover, marine use of NaBH4 is demonstrated, and the pros and cons of the NaBH4 hydrogen storage method are stated. According to evaluations, whereas advantages can be sorted as fuel availability, fuel recyclability, mild storage conditions, exothermicity of reaction, pressure flexibility, and H2 purity, challenges can be sorted as high costs, catalyst deactivation, regeneration, and practical/technical implementation issues. The great potential of NaBH4 marine use (against road/aerial vehicles) is water availability, no need to carry all the required water for the entire journey, and reduced system weight/volume by this way. [ABSTRACT FROM AUTHOR]

This study explores the use of sebacic acid, a catalyst not previously examined in the literature, for hydrogen production from NaBH4 through methanolysis and ethanolysis reactions. Solutions of sebacic acid with concentrations ranging from 0.1 M to 0.4 M were prepared and tested. At a concentration of 0.3 M, 90% of the hydrogen from a 0.33 M NaBH4 solution was released within 3 s, and full release was achieved in 4 s. Hydrogen production rates reached 4500 mL/min for ethanolysis and 4845 mL/min for methanolysis, with methanolysis reactions proving faster. The activation energies for methanolysis and ethanolysis were calculated as 7.17 kJ/mol and 52.3 kJ/mol, respectively. These results demonstrate that sebacic acid enables rapid and efficient hydrogen production, offering a new approach that significantly advances current hydrogen production methods. [ABSTRACT FROM AUTHOR]

The compound p-Nitrophenol (p-NP) is widely recognized as a highly toxic nitro-aromatic substance that urgently requires emission control. Reducing p-NP to p-aminophenol (p-AP) not only decreases its toxicity and mineralization properties in nature but also provides a key raw material for the chemical and pharmaceutical industries. The study used coal fly ash (CFA) as a catalyst carrier for synthesizing the p-NP reduction catalyst. Using CFA as an alternative option not only reduces costs but also achieves the objective of treating waste with waste compared to utilizing commercial solid materials for synthesizing catalysts. By employing hydrochloric acid and sodium hydroxide pretreatment methods, the physicochemical properties of CFA are significantly improved, enhancing the dispersion of palladium (Pd) nanoparticles. The structural features of the prepared samples were characterized using various surface analysis techniques, and both intermittent and continuous modes were experimentally tested for the model catalytic reaction involving the sodium borohydride (NaBH4)-mediated reduction of p-NP. The results demonstrate that CFA has potential in wastewater treatment. [ABSTRACT FROM AUTHOR]

The reaction of berberine derivatives containing at the O-9 position N,N-disubstituted acetamide fragments with sodium borohydride in methanol at 0 °C leads to a mild reduction of the "C" cycle with the formation of corresponding tetrahydroberberine derivatives with moderate to good yields. [ABSTRACT FROM AUTHOR]

Silver nitrate (AgNO3), trisodium citrate dihydrate (C6H5Na3O7 · 2H2O), sodium borohydride (NaBH4), and L-ascorbic acid (C6H8O6) were combined in distilled water to create a triangular silver nanoprism particle (AgNPRP) solution. UV-visible (UV-vis) spectroscopy at wavelengths of 350–460 nm and 580–700 nm was observed, and as a result of them, the successful formation of the triangular AgNPRPs was confirmed. The prepared silver nanoprism particles were characterized by X-ray diffraction(XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy(SEM), and transmission electron microscopy(TEM) and employed for the colorimetric detection of platinum(IV) ions in an aqueous solution containing Pt4+ ions. The color of the aqueous silver nanoprism particle solution, containing Pt4+ ions, changed from blue to light brown before turning colorless. Using UV-vis spectrophotometry, the detection limit of the Pt4+ ion concentration was determined to be 6.23 μM in an aqueous solution of silver nanoprism particles. The proposed method was applied for detecting Pt4+ ions in tap water samples. [ABSTRACT FROM AUTHOR]

In this study, a natural zeolite supported Co-B catalyst (Co-B/Zeolite) with a Co content of 10 wt.% was prepared by impregnation and chemical reduction method to release hydrogen gas from an alkaline sodium borohydride (NaBH4) solution. The synthesized catalyst was characterized with various characterization techniques, including X-ray diffraction (XRD), X-ray fluorescence (XRF), inductively coupled plasma mass spectroscopy (ICP-MS), Brunauer–Emmett–Teller (BET), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), Fourier transform infrared (FTIR), and X-ray photoelectron spectroscopy (XPS), etc. It was found that the BET specific surface area of Co-B/Zeolite (26.03 m2 g−1) was roughly double that of the zeolite (13.12 m2 g−1). The Co ratio in the catalyst was found to be 12.02 wt.% by EDX analysis. ICP-MS examination of the catalyst revealed a B/Co atomic ratio of 0.64. No peaks associated with Co-B were observed in the XRD pattern of the catalyst, indicating the amorphous nature of the component. Parameters that have significant effects on the hydrolysis reaction, such as catalyst amount, sodium hydroxide and sodium borohydride concentrations, and reaction temperature, were investigated. The hydrogen generation rate (HGR) was found to be 1732 mL min−1 gcat−1 in the presence of 100 mg of Co-B/Zeolite in 5 wt.% NaOH and 5 wt.% NaBH4 solution at 50 °C. The experimental results were well fitted to the zero-order kinetic model (k0 = 0.0296–0.1619 mol min−1 gcat−1 for 20–50 °C). The activation energy (Ea) of the catalytic reaction was found to be 44.98 kJ mol−1. Meanwhile, the reusability evaluations showed that the catalyst preserves high stability and can still sustain 73% of its initial activity after 5 catalytic cycles. [ABSTRACT FROM AUTHOR]

Sodium borohydride induces the oxidative expansion of the imine derived from isatin and phenylethylamine to form 3-phenethylquinazoline-2,4(1H,3H)-dione. It has been proposed that this transformation occurs by in situ formation of hydroperoxyl anions by a reaction between sodium borohydride and atmospheric oxygen. To contribute to understanding this oxidative expansion, the reaction between the imine derived from isatin and phenylethylamine with hydrogen peroxide was studied in this work. From this reaction, 3-phenethylquinazoline-2,4(1H,3H)-dione was isolated and two by-products were identified: N-phenethyl-2-(3-phenethyl-ureido)-benzamide and methyl(2-(phenethylcarbamoyl)phenyl)carbamate. This article analyses the structure of these by-products and proposes a mechanism that explains the reaction. It was established that the reaction of the imine derived from isatin and phenylethylamine with hydrogen peroxide produces a mixture of three compounds: 3-phenethylquinazoline-2,4(1H,3H)-dione, N-phenethyl-2-(3-phenethyl-ureido)-benzamide and methyl(2-(phenethylcarbamoyl)phenyl)carbamate. A reaction mechanism is proposed that explains this behaviour [ABSTRACT FROM AUTHOR]

A disordered sodium borohydride (NaBH4) environment to facilitate Na+ mobility was achieved by partially hydrolyzing NaBH4 and this significantly improved Na+ ionic conductivity to 10−3 S cm−1 at 75 °C. The reaction rate of NaBH4 self-hydrolysis, however, is determined by several parameters, including the reaction temperature, the molar ratio between NaBH4 and H2O, and the pH value; but these factors are hard to control. In this paper, poly(ethylene oxide) (PEO), capable of retaining H2O through hydrogen bonding, was used in an attempt to better control the amount of H2O available for NaBH4 self-hydrolysis. This strategy led to the ionic conductivity of 1.6 × 10−3 S cm−1 at 45 °C with a Na+ transference number of 0.54. The amorphous nature of the PEO matrix in hydrolyzed NaBH4 is also believed to provide a conduction path for fast Na+ conduction. [ABSTRACT FROM AUTHOR]

Schematic presentation of synthesis of Cu- BDC MOF nanosheets and rGO/ Cu- BDC MOF nanosheets. [Display omitted] • Two-dimensional rGO/Cu-BDC MOF nanocomposites were successfully synthesized. • An efficient catalytic reduction of 4-NP to 4-AP is accomplished using rGO/Cu-BDC MOF. • The synergy between Cu-BDC MOF and rGO enhances both the 4-nitrophenol reduction and electrochemical properties. Two-dimensional nanosheets, with their distinct characteristics, are widely used in various applications such as water splitting, supercapacitors, catalysis etc. In this research, we produced Cu-BDC MOF nanosheets by using Cu 2 O nanotubes for metal ions and H 2 BDC as the organic linker. We combined these Cu-BDC MOF nanosheets with reduced graphene oxide (rGO) to form a nanocomposite. The collaboration between Cu-BDC MOF and rGO boosts both the catalytic reduction of 4-nitrophenol and the electrochemical capabilities. The conversion of 4-nitrophenol to 4-aminophenol is achieved using sodium borohydride as both a reducing agent and a catalyst. The study explores the impact of different concentrations of 4-nitrophenol and sodium borohydride on catalytic efficiency. The increase in sodium borohydride concentration enhances catalytic efficiency by providing more BH 4 − ions and electrons for the reduction process. The catalytic reduction process adheres to the Langmuir–Hinshelwood mechanism with apparent pseudo-first-order kinetics. Specifically, Cu-BDC MOF and rGO/Cu-BDC MOF exhibit specific capacities of 468.4 mA h/g and 656.4 mA h/g at a current density of 2 A/g, respectively, while also enhancing the operating voltage window. Therefore, electrodes based on rGO/Cu-BDC MOF nanosheets present a novel approach for environmental remediation and energy storage applications across various fields. [ABSTRACT FROM AUTHOR]

In this study, carbon nanotube (CNT) supported M(Bi, Cu, Fe, Nb) catalysts were prepared by the sodium borohydride (SBH) reduction method for hydrazine electro-oxidation. The structural and morphological surface analyses of the 3% Cu/CNT catalyst were characterized by X-Ray diffraction (XRD) and scanning electron microscopy-energy dispersive X-Ray (SEM-EDX) and mapping analyses. The catalytic activities of the catalysts were investigated by cyclic voltammetry (CV) analysis. The 3% Cu/CNT catalyst exhibited the best catalytic activity compared to other catalysts, with a specific activity of 34.7 mA/cm2 . The electrocatalytic performance of the 3% Cu/CNT catalyst was investigated with different scan rates. It was also found to have the best resistance by electrochemical impedance spectroscopy (EIS) analysis. It has the potential to be a promising anode catalyst for direct hydrazine fuel cells (DHYPs). [ABSTRACT FROM AUTHOR]

Two chiral ferrocenylamine alcohols of (R)-[Fe(η5-C5H5){η5-C5H4CH2NHCH(iPr)(CH2OH)}] (1) and (R)-[Fe(η5-C5H5){η5-C5H4CH2NHCH(C6H5)(CH2OH)}] (2) were synthesized by condensation reaction of ferrocenylformaldehyde and chiral aminoalcohols followed by the reduction with sodium borohydride. The crystal structures of the two compounds were determined by single crystal X-ray diffraction. Compound 1 crystallizes in the orthorhombic space group P21212 with a = 16.600(8) Å, b = 28.990(14) Å, c = 6.531(3) Å, and Z = 8. Compound 21.13H2O crystallizes in the monoclinic space group I2 with a = 22.671(4) Å, b = 6.2481(10) Å, c = 22.112(4) Å, β = 96.763(12)°, and Z = 8. [ABSTRACT FROM AUTHOR]

Hydrogen (H2) storage is one of the most problematic issues regarding the widespread use of hydrogen, and solid-state hydrogen storage materials are promising in this regard. Hydrogen storage by sodium borohydride (NaBH4) takes attention with its advantages and idiosyncratic properties. In this study, potentials and challenges of sodium borohydride are evaluated considering storage conditions, safety, hydrogen purity, storage capacity, efficiency, cost, and the maturity. Moreover, marine use of NaBH4 is demonstrated, and the pros and cons of the NaBH4 hydrogen storage method are stated. According to evaluations, whereas advantages can be sorted as fuel availability, fuel recyclability, mild storage conditions, exothermicity of reaction, pressure flexibility, and H2 purity, challenges can be sorted as high costs, catalyst deactivation, regeneration, and practical/technical implementation issues. The great potential of NaBH4 marine use (against road/aerial vehicles) is water availability, no need to carry all the required water for the entire journey, and reduced system weight/volume by this way.

In the present study, silver nanoparticles were synthesized via green synthesis using fenugreek (Trigonella foenum‐graecum L.) seeds of variety HM 425. The AgNPs were characterized by using UV‐Visible spectroscopy, Particle size analyzer, Field emission scanning electron microscopy coupled to Energy dispersive X‐ray spectroscopy, XRD, High resolution transmission electron microscopy and Fourier Transform Infrared Spectroscopy. The AgNPs were spherical and had an average particle size of 28 nm. The reduction of cationic dyes Methylene blue, Rhodamine B, and an anionic azo dye Methyl Orange by Sodium borohydride was used as a model reaction to investigate the catalytic ability of AgNPs. The results demonstrated an efficient catalytic dye degradation of methylene blue (95.81 %, 25 min, 0.1737±0.01 min−1), Rhodamine B (90.23 %, 15 min, 0.1388±0.01 min−1) and methyl orange (83.63 %, 39 min, 0.0412±0.002 min−1). The synthesized AgNPs had an excellent detection limit of 12.50 μM for Hg2+, making them excellent solid bio‐based sensors for mercury sensing. [ABSTRACT FROM AUTHOR]

This work investigated in‐situ synthesis of porous silica‐nickel‐ruthenium composite catalysts for hydrolysis of ammonia borane. The precursors were prepared with an anionic surfactant, sodium dodecyl sulfate (SDS), to form porous structure in the precursor particles, and the precursors was treated in aqueous solution including sodium borohydride and ammonia borane for in‐situ process to parallelly activate and use the catalysts for hydrolysis of ammonia borane. The result of TEM and nitrogen sorption measurements suggested that the primary particle size of the in‐situ synthesized catalysts decrease with increasing the amount of SDS and sodium chloride as the additive for controlling the primary particle size probably because of the effect of sodium ions to inhibit nuclei growth of the primary particles. From the EDS analyses, the composition of active nickel and ruthenium contents increased with increasing the amount of SDS and sodium chloride except for the highest amount of SDS probably because of adsorption of the metal cations with the excess amount of the surfactant anion to decrease the amount of the metal cations including the catalyst. The in‐situ synthesized catalyst including small size primary particles and high nickel and ruthenium content tended to exhibit high activity for hydrolysis of ammonia borane. [ABSTRACT FROM AUTHOR]

In the present study, silver nanoparticles were synthesized via green synthesis using fenugreek (Trigonella foenum‐graecum L.) seeds of variety HM 425. The AgNPs were characterized by using UV‐Visible spectroscopy, Particle size analyzer, Field emission scanning electron microscopy coupled to Energy dispersive X‐ray spectroscopy, XRD, High resolution transmission electron microscopy and Fourier Transform Infrared Spectroscopy. The AgNPs were spherical and had an average particle size of 28 nm. The reduction of cationic dyes Methylene blue, Rhodamine B, and an anionic azo dye Methyl Orange by Sodium borohydride was used as a model reaction to investigate the catalytic ability of AgNPs. The results demonstrated an efficient catalytic dye degradation of methylene blue (95.81 %, 25 min, 0.1737±0.01 min−1), Rhodamine B (90.23 %, 15 min, 0.1388±0.01 min−1) and methyl orange (83.63 %, 39 min, 0.0412±0.002 min−1). The synthesized AgNPs had an excellent detection limit of 12.50 μM for Hg2+, making them excellent solid bio‐based sensors for mercury sensing. [ABSTRACT FROM AUTHOR]

Aliphatic/aromatic nitrogen-substituted ligands have a very important role in ruthenium chemistry. Polydentate ligands with N-substituted pyridine rings are notable for their ability to easily modify the electronic and steric properties of ruthenium. In this study, the catalytic and biological activities of the [RuCl 2 (NNN)(CH 3 CN)] (NNN: 2,6-di(1H-pyrazol-3-yl)pyridine)) complex were examined for two different applications. Firstly, the superb Ru(II) complex was used to catalyze the methanolysis of NaBH 4 , and its initial rate was calculated as 69360 mLH 2 min−1g cat −1. Secondly, the biological activities of the superb Ru(II) complex were examined. Accordingly, it was determined that this homogeneous complex showed anti-microbial activity on all bacteria used in the study, among the Gram-positive bacteria used in the study, the best result belongs to the Bacillus cereus EMC 19 bacterium with 8 mm, while among the Gram-negative bacteria, the best zone diameter belongs to the Pseudomonas aeruginosa DSM 50071 bacterium with 5 mm. However, it was observed that zone diameters varied between 8 mm and 3 mm. Compared to the control group, it was determined that 0.25 mg/mL concentration had 94.87%, 0.5 mg/mL concentration 96.10%, 1 mg/mL concentration 96.50%, and 2 mg/mL concentration 97.09% cytotoxic activity on the SH-SY5Y cell line. it was determined that all doses of the superb Ru(II) complex used in the study showed anti-cancer activity, but the anticancer activity shown at low doses was statistically more significant at the p < 0.05 level. [Display omitted] • Use of homogeneous superb ruthenium(II) complex during methanolysis of NaBH 4. • Kinetic studies for the superb Ru(II) complex catalyzing the methanolysis of NaBH 4. • Calculation of activation parameters for catalytic the methanolysis reaction. • Investigation of anti-cancer and anti-microbial properties of superb Ru(II) complex. [ABSTRACT FROM AUTHOR]

Enhancing the hydrolysis reaction of NaBH 4 for efficient hydrogen production requires the development of effective catalysts. In this study, the solution particles used for nanoparticles synthesized using the ultrasonic spray (US) method were produced for the first time in N 2 at room temperature in the gas and liquid intermediate phases. It also brings a new approach to synthesizing low-cost and efficient catalysts using ultrasonic spray technology. The proposed method involves US the CoCl 2 solution into the NaBH 4 solution to reduce cobalt, producing catalysts for hydrogenation. This innovative approach pioneers a gas-liquid interface reaction for metal reduction. The resulting catalysts were characterized using SEM, XRD, XPS, TEM, BET and FT-IR analysis. The influence of NaOH/NaBH 4 concentration, solution temperature, and catalyst amount on hydrogen production rate was investigated, and kinetic parameters were analyzed to understand the reaction kinetics better. The hydrogen production rates of US-Co and reduction method (RM) Co catalysts under the same conditions were calculated as 3995 ml H2 /min.g cat and 1245 ml H2 /min.g cat , respectively. The activation energy values calculated for the NaBH 4 hydrolysis of the US-Co catalyst using the nth-order and Langmuir-Hinshelwood kinetic models are 46.75 kJ/mol and 46.87 kJ/mol, respectively. Therefore, it can be concluded that the Langmuir-Hinshelwood kinetic model is consistent with the nth-order kinetic model. Experimental results showed that the ultrasonic spray method is very effective in producing active metal catalysts, offering promising opportunities for catalytic advances. [Display omitted] • A novel method of ultrasonic spray was improved for Co NPs pioneering a gas and liquid interface reaction. • The US-Co is highly active for NaBH 4 with an H 2 production rate of 3995 ml H2 /min.g cat at 30 °C. • The activation energy was calculated to be 46.75 kJ/mol with US-Co NPs. [ABSTRACT FROM AUTHOR]

This work looks at the effects of a varying concentration, soak time, pH and temperature on the sorption of tetraammineplatinum(II) chloride (Pt-Ammine) in Nafion-117 films in the context of the electroless plating of ionic polymer–metal composites (IPMCs). Sorption is characterised by atomic absorption spectroscopy. A definitive screening design carried out determined all four factors to be significant for further analysis using response surface modelling. A duplicated central composite design (CCD) was utilised to characterise how the four factors affect the sorption amount and efficiency. Regression models for both responses were of poor fit. Nevertheless, key insights were obtained on the effects of the process parameters on sorption behaviour. The results indicate that above 0.5 g/L Pt-Ammine sorption, the platinisation of 10 × 50 mm IPMC samples through sodium borohydride reduction becomes redundant by the surface resistance metric. IPMCs with surface resistance values of approximately 2.5 Ω/square were obtained through only one round of chemical reduction. Varying surface morphologies and electrode thicknesses were analysed under a scanning electron microscope. The CCD parameter settings were validated. Recommended settings for optimised Pt-Ammine sorption in 10 × 50 mm Nafion-117 films were identified as follows: 1.0 g/L Pt-Ammine concentration, 24 h soak time, pH of 3 and temperature of 20 °C. [ABSTRACT FROM AUTHOR]

NiO nanoparticles were synthesized from pine cone extract by green synthesis method, which is a simple, cost-effective, environmentally friendly and sustainable method. The particle size of NiO nanoparticles was determined to be in the range of 10–25 nm by X-diffraction differential and transmission electron microscope analysis, and the bandgap energy of NiO nanoparticles was determined to be 2.66 eV. The catalytic effect of NiO nanoparticles in both microwave-assisted sodium borohydride hydrolysis and photocatalytic reduction of methylene blue was examined and it was determined that they had a high catalytic effect in both applications. It was determined that the hydrogen production rate in sodium borohydride hydrolysis was 1135 mL/g/min. The activation energy of sodium borohydride hydrolysis is 29.69 kJ/mol and 29.59 kJ/mol for the nth-order and Langmuir Hinshelwood kinetic models, respectively. In the photocatalytic reduction of methylene blue with NaBH4, it was determined that the reduction did not occur in the absence of a catalyst, but in the presence of the catalyst, the reduction occurred 98% in 3 min. It was determined that NiO nanoparticles were used five times in the photocatalytic reduction of methylene blue and the reduction efficiency for the fifth time was 93%. It was determined that the photocatalytic reduction of methylene blue was pseudo-first order and the rate constant was 1.63 s−1. It was determined that NiO nanoparticles synthesized by the environmentally friendly green synthesis method can be used as catalysts for two different applications. NiO nanoparticles were synthesized from pinecone extract in a simple, cost-effective, and green method. The synthesized NiO nanoparticles were characterized using various characterization techniques. NiO nanoparticles have high activity both in the photocatalytic reduction of methylene blue and in the hydrolysis of sodium borohydride, and they are catalysts with high activity in two different applications. Photocatalytic reduction of methylene blue with uncatalyzed NaBH4 was not achieved and was completed in 3 min in the presence of NiO nanoparticle catalyst. It was determined that the hydrogen production rate in sodium borohydride hydrolysis was 1135 mL/g/min. NiO nanoparticle catalysts have low activation energy for sodium borohydride hydrolysis. [ABSTRACT FROM AUTHOR]

The presented studies aimed to evaluate the peripheral coordinating properties of a novel porphyrinoid family representative preceded by its synthesis for potential sensing purposes. Two synthetic pathways were employed to a obtain maleonitrile derivative, further used as a starting material in the cyclotetramerization reaction. In the first one, DAMN was used in sequential double-reductive alkylation with 2-thiophene-carboxyaldehyde and sodium borohydride. In the second, DAMN was used in a one-pot reaction with 2-thiophene-carboxyaldehyde in the presence of a 5-ethyl-2-methylpyridine borane complex in methanol and acetic acid. Following the Linstead approach, the cyclization reaction led to a novel symmetrical magnesium(II) octaaminoporphyrazine with methyl(2-thiophenylmethylene) substituents. The macrocycle's electrochemical properties were assessed by cyclic and differential pulse voltammetries revealing one reduction and two oxidation peak potentials. The additional spectroelectrochemical measurements showed formation of a cationic form of the macrocycle at an applied potential of 0.6 V. The coordinating properties due to the palladium ion of novel porphyrazines were measured with the use of titration combined with UV–vis spectrometry. The titration of Pd2+ revealed the good sensing activity of porphyrazine in the range of 0.1 to 5 palladium molar equivalents. In addition, Pd2+ ions coordination was also assessed by electrochemical studies, indicating the peak potential shift of 0.1 V in the presence of metal cations. DFT calculations showed the good agreement between theoretical and experimental data in the UV–vis and 1H NMR studies. [ABSTRACT FROM AUTHOR]

Co–B/Chi, which is made up of highly distributed Co–B particles, was synthesized by impregnation and chemical reduction methods. Scanning electron microscopy, energy-dispersive spectroscopy, X-ray diffraction, Brunauer–Emmett–Teller adsorption and Fourier transform infrared spectroscopy analyses were used to describe the morphology and microstructure of Co–B/Chi. The synthesized catalyst showed high catalytic activity in the hydrolysis reaction of NaBH4. The unsupported Co–B samples were compared with the chitin-supported Co–B catalyst, and the result showed that higher catalytic activity and good cycling stability for NaBH4 hydrolysis were obtained with the chitin-supported catalyst. The reaction conditions were investigated to achieve high hydrogen production. The maximum rate of hydrogen production was obtained at 40 °C and 20 mg catalyst amount. At ideal conditions, the hydrolysis reaction's activation energy was determined to be 51.65 kJ mol−1. It is indicate that Co–B/Chi is a viable low-cost catalyst for the hydrolysis of NaBH4 for hydrogen production. [ABSTRACT FROM AUTHOR]

The kinetics of sodium borohydride catalytic hydrolysis with cobalt catalysts Co3O4/ZnO, Co/ZnO, Co3O4/zeolite, Co/zeolite, Co(OH)2, Co3O4, and Co–B was studied, and the kinetic characteristics of the process were compared with the same characteristics of the catalytic hydrolysis of ammonia borane. The concentrations of sodium borohydride and NaOH in aqueous solution in all cases were 0.064 and 0.06 M, respectively. The apparent activation energy and the rate of hydrogen evolution during the sodium borohydride hydrolysis in the temperature range of 35–80°C were determined in each case. The kinetic data were processed using zero-order, first-order, and Langmuir–Hinshelwood reaction models. The apparent activation energies for the sodium borohydride hydrolysis ranged from 37.0 for Co3O4 to 72.6 kJ/mol for Co3O4/ZnO. These values exceeded similar values for the ammonia borane hydrolysis, which were in the range of 26.0–47.4 kJ/mol. A higher rate of hydrogen evolution was observed during the sodium borohydride hydrolysis compared to ammonia borane when using these catalysts, except for Co–B and Co/ZnO catalysts. The maximum rates of hydrogen evolution 3510 and 3140 mL of H2 (g cat)–1 min–1 were observed when using Co(OH)2 and Co–B catalysts, respectively. [ABSTRACT FROM AUTHOR]

At present, the chemical activation method is used to prepare activated carbon from poplar sawdust. Co/activated carbon (Co/AC) is synthesized by the sodium borohydride (SBH, NaBH 4) reduction method. The catalysts are characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy-X-ray energy dispersion (SEM-EDX) analytical techniques. The catalytic activity, stability, and resistance of the Co/AC catalysts are determined by electrochemical analyses such as cyclic voltammetry (CV), chronoamperometry (CA), and electrochemical impedance spectroscopy (EIS), respectively. The 1 % Co/AC catalyst exhibits the highest catalytic activity at a specific activity of 3.964 mA/cm2 compared to other catalysts. Furthermore, it has shown long-term stability and low resistance. The effect of the catalyst, sodium borohydride and methanol amounts, and temperature parameters on the initial hydrogen generation rate are determined. The initial hydrogen generation rate of the 1 % Co/AC catalyst is obtained as 26053.2 mL/min.gcat at optimum parameters such as 0.025 g catalyst, 0.15 g NaBH 4 , 6 mL methanol, and 60 °C temperature. As a result, 1 % Co/AC catalyst is promising both as an anode electrode material and catalyst for sodium borohydride methanolysis. • The activated carbon (AC) is prepared by the chemical activation method with phosphoric acid (H 3 PO 4) of poplar sawdust. • AC-supported Co catalysts are successfully synthesized by the NaBH 4 reduction method. • The characterization results reveal that the desired structure has been formed. • Co/AC catalyst exhibits the highest catalytic activity (3.964 mA/cm2) and the initial HGR (26053.2 mL/min.gcat). [ABSTRACT FROM AUTHOR]

In this work, aqueous sodium borohydride and ammonia solution as dual precipitating reagents were explored one after another via one-pot synthesis to develop Ce-based three different luminescent materials. The borate, i.e., (Y, Al) BO 3 , and mixed borate-oxide, i.e., YBO 3 -YAG, were obtained at 1000 °C and 1200 °C, respectively. The mixed borate-oxide was stable up to 1400 °C with increased YAG phase. However, the oxide-based materials consisting of YAG with secondary phases Al 2 O 3 and CeO 2 were confirmed at 1500 °C. The emission behavior confirmed that the borate/mixed borate-oxide showed a deep blue. Further, broad emissions centered at 380/420 nm and 533 nm for the mixed borate-oxide calcined at 1400 °C exhibited lighter blue. However, the color of the oxide, i.e., YAG-based material, showed near white emission due to the equal contribution of these broad emissions. The color of mixed borate-oxide and oxide-based materials was further altered to greenish yellow by switching the excitation wavelength from 354 nm to 425 nm. The electroluminescence behavior further confirmed the generation of white light for epoxy-containing YAG-based powders over a blue LED. The emission behavior of one-pot synthesized different luminescent materials may be explored in illumination, anticounterfeiting, security, fraud deterrent, and the like. [ABSTRACT FROM AUTHOR]

In this study, trimethylolpropane triglycidyl ether/diethylenetriamine (TD) and glutaraldehyde/diethylenetriamine (GD) polymer particles are synthesized as catalysts for hydrogen production from NaBH4 methanolysis and NaBH4 electrooxidation. SEM, FT‐IR and TGA characterization methods are applied to determine the surface morphologies, chemical structures, thermal stability and decomposition of the synthesized polymer particles. The parameters affecting the hydrogen generation rate on NaBH4 methanolysis are investigated and optimum conditions are determined. Under optimum conditions, the hydrogen generation rates of TD and GD polymer particles are obtained as 34903.2 and 97998 mL/min.gcat, respectively. The activation energies of TD and GD polymer particles are also calculated as 16.86 and 18.14 kJ/mol, respectively. The catalytic activities of polymer particles as anode catalysts in NaBH4 electrooxidation are determined by CV, CA, EIS analyses. The specific activities of TD and GD polymer particles are acquired as 0.54 and 0.64 mA/cm2, respectively. These results indicate that the synthesized polymer particles are promising catalysts for electrooxidation and methanolysis of sodium borohydride. [ABSTRACT FROM AUTHOR]

One of the biggest issues affecting the entire world currently is water contamination caused by textile industries' incapacity to properly dispose their wastewater. The presence of toxic textile dyes in the aquatic environment has attracted significant research interest due to their high environmental stability and their negative effects on human health and ecosystems. Therefore, it is crucial to convert the hazardous dyes such as methyl orange (MO) azo dye into environmentally safe products. In this context, we describe the use of Copper Nitroprusside Chitosan (Cu/SNP/Cts) nanocomposite as a nanocatalyst for the chemical reduction of azodyes by sodium borohydride (NaBH4). The Cu/SNP/Cts was readily obtained by chemical coprecipitation in a stoichiometric manner. The X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared (FT-IR) spectroscopy were applied to investigate chemical, phase, composition, and molecular interactions. Additionally, Scanning electron microscope (SEM) was used to examine the nanomaterial's microstructure. UV–vis spectroscopy was utilized for studying the Cu Nitroprusside Chitosan's catalytic activity for the reduction of azodye. The Cu/SNP/Cts nanocomposite demonstrated outstanding performance with total reduction time 160 s and pseudo-first order constant of 0.0188 s−1. Additionally, the stability and reusability study demonstrated exceptional reusability up to 5 cycles with minimal activity loss. The developed Cu/SNP/Cts nanocomposite act as efficient nanocatalysts for the reduction of harmful Methyl orange azodye. [ABSTRACT FROM AUTHOR]

In this study, the applicability of a Co2+-doped catalyst [(Co-Ver) cat ] fabricated from clay vermiculite ore for the synthesis of hydrogen from sodium borohydride was investigated. FT-IR, XRD, SEM, Brunauer-Emmett-Teller (BET) analysis, and X-ray fluorescence (XRF) studies were used to characterize the synthesized (Co-Ver) cat. After activation with 1 M HCl, 0.15 g the 30% Co2+-doped catalyst (7% NaOH, 2.5% NaBH 4 , 30 °C process temperature) produced the maximum catalytic activity. Under these conditions, the hydrogen generation rate of 1991,39 ml g Co −1 min−1was achieved with the (Co-Ver) cat. The NaBH 4 hydrolysis reaction had an activation energy of 43.58 kJ mol−1 and a reaction rate order (n) of 0.18. It was also determined that the prepared (Co-Ver) cat exhibited good reusability. The reusability of the (Co-Ver) cat prepared from vermiculite ore was high, and 91.78% of the expected hydrogen amount was obtained as a result of its 10th use. • A cobalt doped catalyst was prepared from raw vermiculite ore for NaBH 4 hydrolysis. • The hydrogen generation rate was calculated as 1991.39 ml g Co −1 min−1 at 30 °C. • The activation energy for NaBH 4 hydrolysis was founded 43.58 kJ mol−1 [ABSTRACT FROM AUTHOR]

Sodium borohydride (NaBH 4) has been generally studied as a source of hydrogen (H 2) due to its important advantages with the development of support materials and catalysts for H 2 release in the energy sector. In this context, we carry out molecular dynamics (MD) simulations by using extended tight-binding (xTB) model Hamiltonian based on density functional theory (DFT) and analyze the Ca 12 Al 14 O 33 functional material doped X metals (X = Co, Ru, Rh) as a catalyst with [Co(III)(N 3) 3 (C 9 H 8 N 2) 2 ] as complex compound with amine ligand from NaBH 4 hydrolysis for H 2 production. The use of a functional material doped by X metals causes to the high rate in H 2 production when compared to without functional material doped by X metals. The increase of complex compound with amine ligand facilitates H 2 production. Rh on the functional material displays the best catalytic performance compared to Ru and Co to increase the H 2 production rate. Also, the increment of temperature has a positive effect on the H 2 production rate with functional material doped Co, Ru and Rh metals. Thus, Ca 12 Al 14 O 33 support material doped with noble metals appears promising as an innovative catalyst for H 2 production. [Display omitted] • X metals on the Ca 12 Al 14 O 33 functional material and complex compound are designed. • Addition of complex compound with amine group leads to increase of 13% on H 2. • Addition of Rh catalyst on the Ca 12 Al 14 O 33 supplies the H 2 increasing of 25%. • Rh-doped Ca 12 Al 14 O 33 increases 6 times to H 2 production rate. • MD simulations confirm the formation of H 2 bonding using the NABH 4 hydrolysis. [ABSTRACT FROM AUTHOR]