Precursor Salts Research Articles

Stacked ZnS multilayers of ZnS(en)0.5 hybrids with enhancing photocatalytic performance for H2 production

Zinc sulfide hybrids with different stacked ZnS multilayers were prepared using a chemical precipitation method in a solvent mixture of Ethylenediamine:Water:Butanol via two routes - nitrate and acetate salt precursors. The impact of butanol solvent contents (30 and 60 vol%) on the formation of orthorhombic-ZnS(en)0.5 hybrid with different stacking of ZnS layers was comprehensively analyzed using X-ray diffraction, Fourier Transform Infrared, X-ray photoelectron spectroscopy, and diffuse reflectance spectroscopy. Scanning electron microscopy was employed to study the influence of the mixture solvent on particle size and morphology of the resulting ZnS(en)0.5 hybrid micro flakes or nanosheets. The photocatalytic response was evaluated through hydrogen production reactions using low photocatalyst load under UV light irradiation, conducted over four reaction cycles. A significant increase in hydrogen production rate (4.6 and 4.0 times more active) was achieved for the exfoliated ultrathin nanosheet ZnS(en)0.5 hybrid prepared with lower butanol contents from the nitrate and acetate route, respectively. This enhancement was attributed to the reduced size of the nanosheets of stacked ZnS multilayers, which resulted from the incorporation of 30 vol% of butanol during the synthesis. Overall, the findings indicate that the Ethylenediamine:Butanol solvent system plays a crucial role in tuning the degree of ZnS stacking layers, the particle size, and morphology of ZnS(en)0.5 hybrids, leading to improved photocatalytic performance in hydrogen production reactions.

Effects of Cobalt Salt Precursors on the Characteristics and photo-Fenton Catalytic Performance of Cobalt Ferrite Nanoparticles Synthesized by the Solvothermal Method

Effects of Cobalt Salt Precursors on the Characteristics and photo-Fenton Catalytic Performance of Cobalt Ferrite Nanoparticles Synthesized by the Solvothermal Method

Biosynthesis of Copper Nanoparticles with Medicinal Plants Extracts: From Extraction Methods to Applications.

Copper nanoparticles (CuNPs) can be synthesized by green methods using plant extracts. These methods are more environmentally friendly and offer improved properties of the synthesized NPs in terms of biocompatibility and functional capabilities. Traditional medicine has a rich history of utilization of herbs for millennia, offering a viable alternative or complementary option to conventional pharmacological medications. Plants of traditional herbal use or those with medicinal properties are candidates to be used to obtain NPs due to their high and complex content of biocompounds with different redox capacities that provide a dynamic reaction environment for NP synthesis. Other synthesis conditions, such as salt precursor concentration, temperature, time synthesis, and pH, have a significant effect on the characteristics of the NPs. This paper will review the properties of some compounds from medicinal plants, plant extract obtention methods alternatives, characteristics of plant extracts, and how they relate to the NP synthesis process. Additionally, the document includes diverse applications associated with CuNPs, starting from antibacterial properties to potential applications in metabolic disease treatment, vegetable tissue culture, therapy, and cardioprotective effect, among others.

Green Synthesis of ZnO/CuO Nanocomposites Using Parsley Extract for Potential In Vitro Anticoccidial Application.

In this study, a simple, low-cost, and environmentally friendly method for the green synthesis of ZnO/CuO nanocomposites (NCs) using parsley extract was developed. The phytochemical components in the parsley leaf extract reacted with precursor salts in solution and yielded ZnO/CuO NCs. The synthesis of the green-synthesized NCs was confirmed via various characterization techniques, including UV-vis spectroscopy, X-ray diffraction (XRD) analysis, energy-dispersive X-ray (EDX), transmission electron microscopy (TEM), and field emission scanning electron microscopy (FE-SEM). Subsequently, the NCs were subjected to rigorous in vitro evaluation of their anticoccidial properties. The results showed that the NCs had a spherical shape within an average particle size of around 70 nm. The green-synthesized NCs were evaluated for their in vitro anticoccidial activity against Eimeria spp. The findings showed that the NCs exhibited a significant anticoccidial effect, with a maximum inhibition of 55.3 ± 0.32% observed at a concentration of 0.5 mg/mL. The exposure to the NCs resulted in notable alterations in the ultrastructure of the oocysts when compared to the control group. The ZnO/CuO NCs synthesized from the parsley leaf extract showed promising potential against coccidiosis and could be used in biomedical applications. Further investigation using an in vivo model is required to ascertain the efficacy of NCs as anticoccidial agents.

Unveiling the formation mechanism of polydisperse iron oxide nanoparticles in coprecipitation route

Coprecipitation is the simplest, fastest, and most inexpensive method for preparing metal oxide nanoparticles (NPs). It is considered one of the most convenient methods for simultaneously precipitating two or more aqueous metal salt precursors (such as chlorides, nitrates, oxychloride, etc.) into NPs in a basic solvent, yielding uniform composition. However, the main drawback of this route is the production of NPs with a broad size distribution (polydispersed particle formation), which limits their use in various applications. The present work addresses the experiments and formation mechanism of polydispersed iron oxide magnetite (Fe3O4) NPs using this route. Experiments involving the drop-wise addition of mixed ferric (Fe3+) and ferrous (Fe2+) chloride salt solutions to NaOH base solution at room temperature resulted in a polydispersed Fe3O4 NP system containing both large and small particles at the end of 30 min of the reaction. A mechanism is proposed to explain the formation of these polydispersed Fe3O4 NPs based on the time scales of different individual particle formation events and the experimental aging time. The mechanism elucidates that the time scales of events such as Fe3O4 nucleation, diffusional-limited and Ostwald ripening growth of small and large particles, and the coagulation of two small particles or a small particle with a large particle are smaller, and completed within the experimentally allowed aging time. Conversely, the coagulation time for two large particles exceeds the experimental time, preventing complete coagulation. As a result, incomplete coagulation of large particles and the completion of all other events lead to the formation of a polydispersed Fe3O4 NP system at the end of the synthesis. The combined experiments and time scale-based mechanism explain the polydispersed NP formation in the coprecipitation route, and the insights gained from this understanding can be beneficial for optimizing synthesis conditions to achieve a controlled size distribution of Fe3O4 and other NP systems.

Comparative Study of Guanidine-, Acetamidine- and Urea-Based Chloroaluminate Electrolytes for an Aluminum Battery.

Aluminum-based batteries are a promising alternative to lithium-ion as they are considered to be low-cost and more friendly to the environment. In addition, aluminum is abundant and evenly distributed across the globe. Many studies and Al battery prototypes use imidazolium chloroaluminate electrolytes because of their good rheological and electrochemical performance. However, these electrolytes are very expensive, and so cost is a barrier to industrial scale-up. A urea-based electrolyte, AlCl3:Urea, has been proposed as an alternative, but its performance is relatively poor because of its high viscosity and low conductivity. This type of electrolyte has become known as an ionic liquid analogue (ILA). In this contribution, we proposed two Lewis base salt precursors, namely, guanidine hydrochloride and acetamidine hydrochloride, as alternatives to the urea-based ILA. We present the study of three ILAs, AlCl3:Guanidine, AlCl3:Acetamidine, and AlCl3:Urea, examining their rheology, electrochemistry, NMR spectra, and coin-cell performance. The room temperature viscosities of both AlCl3:Guanidine (52.9 cP) and AlCl3:Acetamidine (76.0 cP) were significantly lower than those of the urea-based liquid (240.9 cP), and their conductivities were correspondingly higher. Cyclic voltammetry (CV) and linear sweep voltammetry (LSV) showed that all three electrolytes exhibit reversible deposition/dissolution of Al, but LSV indicated that AlCl3:Guanidine and AlCl3:Acetamidine ILAs have superior anodic stability compared to the AlCl3:Urea electrolyte, as evidenced by anodic potential limits of +2.23 V for both AlCl3:Guanidine and AlCl3:Acetamidine and +2.12 V for AlCl3:Urea. Coin-cell tests showed that both AlCl3:Guanidine and AlCl3:Acetamidine ILA exhibit a higher Coulombic efficiency (98 and 97%, respectively) than the AlCl3:Urea electrolyte system, which has an efficiency of 88% after 100 cycles at 60 mA g-1. Overall, we show that AlCl3:Guanidine and AlCl3:Acetamidine have superior performance when compared to AlCl3:Urea, while maintaining low economic cost. We consider these to be valuable alternative materials for Al-based battery systems, especially for commercial production.

Facile green synthesis of highly stable, water dispersible carbohydrate conjugated Ag, Au and Ag-Au biocompatible nanoparticles: Catalytic and antimicrobial activity

Highly stable carbohydrate conjugated silver, gold and bimetallic silver-gold alloy biocompatible and nearly monodisperse nanoparticles (NPs) have been synthesized through bio-reduction of aqueous solution of corresponding metal salt precursors mediated by aqueous extracts of a high altitude lichen, Lobaria retigera. The biomolecule accountable for the reduction, stabilization and capping of the metal nanoparticles is identified to be carbohydrates. The as-synthesized carbohydrate conjugated nanoparticles have excellent dispersibilty in water, phosphate, phosphate-buffered saline, and serum media. The resulting nanoparticles were completely stable for several months in water. The nanoparticles were characterized using UV–visible spectroscopy, TEM, EDX, FT-IR, powder XRD, DLS and CV study. Though mostly spherical in shapes, occasionally truncated triangular and rod shapes were also noted. The average particle sizes of Ag, Au and Ag-Au alloy nanoparticles as determined from TEM analysis are 14.5 nm, 11.7 nm and 16.3 nm, respectively. Cyclic voltammetry pointed to a relatively high electrode potential barrier for the synthesized nanomaterials. The prepared Ag, Au and Ag-Au alloy nanoparticles served as efficient catalysts for the degradation of hazardous pollutant dye, methyl orange (MO) with rate constat of 0.1496 min−1, 0.1049 min−1, and 0.1882 min−1. The bimetallic Ag-Au nanoparticles exhibited the most accelerated reduction with 90.6% degradation efficiency. The reduction kinetics for the reactions followed a pseudo-first order, kAu < kAg< kAu-Ag. The Ag and Ag-Au alloy NPs showed pronounced antimicrobial activity towards selected bacterial strains while AuNPs lacked any such activity.

Sustainable hybrid biocomposite adsorbents for anion-selective or concerted removal of ionic pollutants: Organic dyes to arsenate

The controlled removal of hazardous ionizable compounds ranging from organic dyes from the textile industry to inorganic anions such as fluoride, sulfate or arsenate in aqueous media presents challenges to this day. This study devised a synthetic strategy to enable anion selective or simultaneous adsorption of anionic and cationic species. Therefore, versatile ternary metal composites (TMCs) were prepared with variable aluminum salt precursors: TMC-S for Al2(SO4)3 and TMC-N for Al(NO3)3 with variable Al3+ content from high to low values (S1>S2>S3>S4; N1≫N3) for the respective TMCs. Characterization was achieved through complementary methods: pHPZC, TGA, PXRD, XPS, 27Al/13C NMR and IR spectroscopy. The TMC surface properties were assessed via dye adsorption with methylene blue (MB) as a model cation, whereas methyl orange (MO) and reactive Black 5 (RB5) served as model anion systems. Sulfate, fluoride and arsenate represented a variety of inorganic anion target pollutant species.The maximum equilibrium adsorption capacity of MO decreased (TMC-S1 to TMC-S4; 0.67 to 0.41 mmol/g), whereas the MB adsorption capacity increased from 0.03 to 0.47 mmol/g. The arsenate adsorption capacity also decreased with decreased aluminum concentration during synthesis from 0.71 mmol/g (TMC-S1) to 0.46 mmol/g (TMC-S4). Arsenate and fluoride were chemisorbed onto the Al-centers, in contrast to the dye probes, which undergo physisorption. Additionally, arsenate was selectively removed from saline samples of groundwater with up to 6000 mg/L sulfate species, which contributes to salinity without altering the adsorption properties. This study hereby highlights the unique role of variable aluminum salt during synthesis to enable facile tailoring of the adsorbent structure and selective anion adsorption (TMC-S1) versus a more general (less selective) adsorption of ionic species (TMC-S4) for multi-component pollutant removal.

Iridium Nanosheet Catalysts Supported on Titanium Oxide for Oxygen Evolution Reaction in Polymer Electrolyte Membrane Water Electrolysis

In order to overcome the disadvantage of intermittent production of renewable energy, Polymer electrolyte membrane water electrolysis(PEMWE), which is one of the technologies of producing hydrogen by electrolyzing water, is attracting attention. For the commercialization of PEMWE, it is important to reduce usage of iridium(Ir) for oxygen evolution reaction(OER) in the anode electrode. Many studies have been reported to reduce the amount of iridium used by developing a catalyst with higher performance than the iridium nanoparticle catalyst used as a commercial catalyst. As one of the strategies, the introduction of support materials that can increase the active area of the catalyst is drawing attention. While carbon-based supports are mainly used in other applications, in OER environments, carbon is easily corroded due to high voltage and strong acid conditions. Therefore, it is necessary to use a metal oxide support with high corrosion resistance. In particular, titanium oxide(TiO2) is one of the suitable support candidates because it is a stable material in an acidic OER environment. However, catalysts loaded on TiO2 with nanoparticles cause an electrical contact problem due to the low electrical conductivity of TiO2, which causes a degradation in activity. Many studies have reported doping methods to increase the conductivity of TiO2, but there are also reports that these methods reduce the durability of support. Thus, a new approach to synthesizing a better structure of catalysts is needed to utilize metal oxide support.Herein, we present an approach to iridium nanosheet (NS) catalysts supported on TiO2(Ir NS/TiO2). Ir NSs were synthesized by an facile method by directly annealing a mixture of Ir precursor and alkali salt. Ir NSs were supported on TiO2 to be utilized as a reaction site and also acts as an electron path to compensate for the low electrical conductivity of TiO2. Ir NS/TiO2 showed superior OER activity and stability under acidic conditions. These results showed that Ir NS/TiO2 could be utilized to reduce the amount of precious metal catalyst in PEMWE and increase the stability of OER supported catalysts.

Solvent-free direct salt precursor mechanochemical synthesis of La0.5Sr0.5Ti0.5Mn0.5O3-δ oxide perovskite and its electrocatalytic behavior as oxygen electrode for solid oxide cells

In this work, a solvent-free mechanochemical route is proposed as a direct salt precursor solid state synthesis for the mixed ionic-electronic conducting (MIEC) Lanthanum Strontium Titanium Manganese oxide perovskite (La0.5Sr0.5Ti0.5Mn0.5O3-δ, LSTM). The resulting mechanochemically synthesized powder is structurally and morphologically characterized and is comprised of fine spherical nanostructures in the sub-micron scale (≤100 nm), with low polydispersity and homogeneous morphology, while the obtained perovskite structure is pure single-phase without any precursor residuals or metal oxide phases. For comparison, conventional synthetic routes (sol-gel and precursor calcination) are presented which result in inferior samples of mixed metal oxides and micron-sized particles. Symmetrical solid oxide cells with single-phase LSTM and LSTM-YSZ composite electrodes reveal a mixed conduction behavior in the temperature range of 700–850 °C under flowing synthetic air atmosphere. With a developed current density of 172 mA cm−2 at 850 °C and +2 V overpotential, and an electrode polarization resistance of 7.5 Ω cm2, perovskite LSTM synthesized by the presented solvent-free direct salt precursor mechanochemical synthesis is therefore proposed as a potential candidate for MIEC electrodes in symmetrical reversible solid oxide cells (r-SOCs).

Bamboo-like tubular nitrogen-doped carbon derived from g-C3N4 as an ultra-high performance anode of potassium-ion battery

Carbon materials are still the most widely studied anode materials for potassium ion batteries (PIBs) attributed to their advantages of wide source, controllability, and environmental friendliness. In this paper, a bamboo-like tubular nitrogen-doped carbon material (CNC) was prepared by using g-C3N4 as the precursor and transition metal salt as the catalyst and template. CNC has the advantages of a bamboo-like tubular structure, rich nitrogen content, and large layer spacing. As anode of PIBs, CNC can deliver an impressive initial reversible capacity of 488.6 mAh/g at 0.1 A/g. At a high current density of 1 A/g, CNC still retains a reversible capacity of 291 mAh/g after 1000 cycles. The excellent performance of CNC anode can be due to the porous bamboo-like tubular structure that promotes K ions diffusion and the rich nitrogen content that provides abundant active sites for K ions.

Production of copper nanoparticle-immobilized chitin nanofibers and their role in plant disease control.

Chitin is used in agriculture to improve crop production; however, its use is limited due to difficulties in its handling. A chitin nanofiber (CNF) overcomes this issue and, due to its elicitor activity, has great potential for crop protection. To expand CNF utilization, a copper nanoparticles-based antimicrobic CNF (CuNPs/CNF) was prepared using a chemical reduction method. The formation of CuNPs was confirmed via scanning electron microscopy. Thermogravimetric analysis revealed that the amount of CuNPs on the CNF was dose-dependent on the precursor salt, copper acetate. CuNPs endowed the CNF with strong antimicrobial activity against Alternaria brassicicola and Pectobacterium carotovorum. Moreover, the CuNPs/CNF reduced pathogen infection in cabbage. The antimicrobial activity and disease prevention of the CuNPs/CNF was increased compared to the corresponding CNF or commercial agrochemical Bordeaux treatment. These results indicate that CuNPs conferred antimicrobial activity on the CNF and increased the efficacy of plant disease protection.

WO3·0.33H2O/carbon quantum dots hybrid nanostructures for efficient electrochemical hydrogen evolution reaction

Low-cost electrocatalysts with good catalytic performance are highly desirable for the sustainable production of hydrogen in order to meet the growing global energy crisis. In this work, WO3·0.33H2O/casein-derived carbon quantum dots hybrid nanostructures were synthesized via hydrothermal synthesis route utilizing casein-derived carbon quantum dots and precursor salts of WO3, and its electrochemical performance as an HER electrocatalyst was investigated. XRD, FESEM, TEM, SAED, XPS, FTIR, and Raman analyses confirmed the structural and compositional features of the WO3·0.33H2O/carbon quantum dots hybrid nanostructures. The electrochemical studies showed an efficient HER activity for WO3·0.33H2O/carbon quantum dots hybrid nanostructure with a low overpotential of 197 mV and a small Tafel slope of 101 mV/dec. The synergic effect of the hydrated tungsten oxide and carbon dots enhanced the conductivity and number of accessible active sites, promoting better mass transport, which was responsible for better HER activity. This work presents a cost-effective and green strategy to develop WO3·0.33H2O/carbon quantum dots hybrid nanostructures as a suitable electrocatalyst for hydrogen production.

A novel high activity MnXFe3−XO4 spinel catalyst for selective catalytic reduction of NO using NH3 prepared by a short process from natural minerals for low-temperature sintering flue gas: Effect of X value on catalytic mechanism

The process of smelting and purifying the catalyst precursor salt from minerals is extremely complex, which directly leads to high catalyst costs and serious secondary pollution. In order to achieve energy saving and emission reduction in the catalyst preparation process, in-situ synthesis of catalyst materials from natural minerals is a new research direction. In this study, we firstly explored the optimal X value of MnXFe3-XO4 for the NH3 selective catalytic reduction of NO (NH3-SCR) reaction, i.e., the Mn, Fe ratio, and then prepared a novel highly active mineral-based pure phase MnXFe3-XO4 spinel NH3-SCR catalyst by natural ferromanganese ore fines with iron-red fines (Fe2O3) allotment through in situ solid-phase synthesis and magnetic separation methods according to this ratio. The results show that the X value of 1.5 (Mn1.5Fe1.5O4) is the best for NH3-SCR reaction. Mn1.5Fe1.5O4 nano-particles (201 nm) has nearly 100 % NO conversion (with 5 % H2O(g)) at 125–300 °C. The combination of characterizations and density functional theory (DFT) calculation shows that the catalytic process of Eley-Rideal (E-R) dehydrogenation is enhanced at both the active site Mn site and Fe site, which is a key factor in the acceleration of the NH3-SCR reaction with increasing X value at the MnXFe3-XO4 surface.

Fabrication of rigid polyimide foams with good mechanical and thermal properties

Rigid polyimide foams (PIFs) were successfully fabricated through thermal foaming of polyester ammonium salt precursors (PEASs) with the addition of a pararosaniline base (PA) as a crosslinker. These foams exhibited good mechanical properties and thermal resistance. The construction of crosslinked structure derived from PA could improve melt viscosity and provide cell walls with sufficient strength to prevent shrinkage, which was conducive to elevating compressive properties. PIFBMP-2 (i.e., repeating unit was 2) exhibited optimal compressive strength of 1.76 and 1.25 MPa at room temperature (RT) and 200 °C, which were increased by 6.6 and 7.9 times compared to PIFBM (0.17 MPa (RT) and 0.11 MPa (200 °C)). Furthermore, a relationship between compressive strength and density was established, showing that the compressive strength is proportional to 2.34 and 2.13 powers of density at RT and 200 °C, respectively. Moreover, PIFs owned excellent thermal properties, the 5% weight loss temperature was higher than 458.9 °C in a nitrogen (N2) atmosphere, and the glass transition temperature was up to 291.3 °C. Additionally, the thermal conductivities of the rigid polyimide foams (PIFs) ranged from 0.058 to 0.094 W m−1 K−1, which makes them highly suitable for potential applications in the fabrication of high-temperature resistant multifunctional composites, particularly in aerospace, defense, and transportation industries.

Fast and easy synthesis of silver, copper, and bimetallic nanoparticles on cellulose paper assisted by ultrasound

This work focuses on a systematic method to produce Ag, Cu, and Ag/Cu metallic nanoparticles (MNPs) in situ assisted with ultrasound on cellulose paper. By tuning the concentration of AgNO3 and CuSO4 salt precursors and ultrasound time, combined with a fixed concentration of ascorbic acid (AA) as a reducing agent, it was possible to control the size, morphology, and polydispersity of the resulting MNPs on cellulose papers. Notably, high yield and low polydispersity of MNPs and bimetallic nanoparticles are achieved by increasing the sonication time on paper samples pre-treated with salt precursors before reduction with AA. Moreover, mechanical analysis on paper samples presenting well-dispersed and distributed MNPs showed slightly decreasing values of Young's modulus compared to neat papers. The strain at break is substantially improved in papers containing solely Ag or Cu MNPs. The latter suggests that the elastic/plastic transition and deformation of papers are tuned by cellulose and MNPs interfacial interaction, as indicated by mechanical analysis. The proposed method provides insights into each factor affecting the sonochemistry in situ synthesis of MNPs on cellulose papers. In addition, it offers a straightforward alternative to scale up the production of MNPs on paper, ensuring an eco-friendly method.

Green and sustainable bio-synthesis of gold nanoparticles using Aspergillus Trinidadensis VM ST01: Heterogeneous catalyst for nitro reduction in water

In this study, a gold nanoparticles (GNPs) have been successfully fabricated by the bio reduction route using soil extract Aspergillus trinidadensis (VM ST01’ OL587588) fungi as a reducing and capping agent without any solvent interference. The GNPs were grown and stabilized by a two-step one-pot method, without any influence of chemical reactants. Characteristics of prepared GNPs were investigated using various microscopic and spectroscopic techniques. GNPs were roughly spherical in shape. Water dispersion study of GNPs has shown a stable dispersion in a broad range of 2–12 pH. The stirring and precursor salt concentration has influenced the kinetics involved in the fabrication process. Stoichiometric data has shown 3.5 × 1020 gold atoms per gram of biomass with diameters of around 35 nm, as determined with High-Resolution Transmission Electron Microscopy (HR-TEM). Zeta potential and Powder X-Ray Diffraction (P-XRD) studies have elucidated the crystalline nature of GNPs. Presence of participating functional groups were examined with Fourier Transform Infra-Red Spectroscopy (FT-IR). Synthesized GNPs were analyzed for surface morphology by Scanning Electron Microscope (SEM). The thermal stability of the lyophilized GNPs sample and capping of the particle were evaluated with Thermo-Gravimetric Analysis (TGA) and had a residual mass of 25% at 306 °C. The Aspergillus trinidadensis capped GNPs have been demonstrated as an efficient heterogeneous catalyst (AtGNHC) for the reduction of 4-Nitrophenol as a model substrate in water. An isolated yield (>95%) of the reduced product in 4 h has shown the effectiveness of the prepared catalyst.

Study of morphological aspects in the efficient adsorptive removal of heavy metal ions using graphene oxide-chitosan based magnetic nanocomposite (0.4Fe0x:6x@GCS)

A one pot approach is followed to achieve an optimized synthesis of a benign magnetic nano composite and its applicability is explored in alleviation of toxic heavy metal ions from contaminated water. Untreated industrial effluents are among one of the major contributors in escalating the levels of heavy metals in residual water and soil, hence posing a serious threat to the humankind and the environment. With the motive in mind to treat such effluents, we fabricated a magnetic ternary nano-composite (NC) Fe0x:x@GCS (x:x is the concentration of Fe(II): concentration of NaBH4) aiming to reduce the levels of heavy metal ions (Pd, Cd, Cu & Ni) in polluted water. The initial concentration of Fe (II) precursor salt and the dosage of the reducing agent (NaBH4) were tactically adjusted to get desirable morphological and structural features in ultimate magnetic Fe0x:x@GCS NC with profound effect in eliminating the heavy metals ions from waste water. The effects of varying these two factors on the overall removal efficiency of heavy metal ions of the Fe0x:x@GCS are studied and analyzed. XRD, SEM & EDS techniques are used for the study of morphological and structural aspects of the synthesized materials and their comparative analysis. The reaction kinetics of the removal process of Pb(II) ions by the Fe0x:x@GCS NC was found best fitted to pseudo second order kinetics and the reaction isotherm was found better explained by Langmuir isotherm. Mechanistic aspects of the removal process of Pb (II) ions could be explained by XRD analysis of NC before and after the treatment with polluted water. Furthermore, to simulate the real waste water conditions, a mixture containing Pb (II), Cd (II), Ni (II) and Cu (II) heavy metal ions was also treated with NC which exhibited the removal efficiency of >99% .

Quantitative Measurement of Compositional Inhomogeneity in NMC Cathodes by X-ray Diffraction

A novel XRD analysis technique is described for quantitatively measuring compositional inhomogeneity in Li[NixMnyCoz]O2 (NMC) cathode materials and NMC precursors. Single-phase rock salt precursors with varying degrees of compositional inhomogeneity were prepared by grinding mixtures of Ni, Mn and Co oxides for different times and then heating. These precursors were then heated with lithium to form cathode materials. A modified Williamson-Hall analysis was used to measure the degree of compositional inhomogeneity in the precursors and the final NMC materials. This analysis showed that precursors made with low grinding times had higher compositional inhomogeneity and that this compositional inhomogeneity was amplified in the final NMC, leading to interlayer mixing and poor electrochemical performance. Higher precursor grinding times lead to more compositionally homogeneous NMC, while even higher compositional homogeneity was achieved by NMC made from conventional hydroxide precursors, with correspondingly improved electrochemical performance. The ability described here to measure the degree of compositional homogeneity in NMC precursors and NMC cathode materials by simple XRD measurements presents a powerful tool for the research and development of NMC and other cathode materials.

Binuclear Macrocyclic Silver(I) Complex of a Bis(carbone) Pincer Ligand: Synthesis and Application as a Carbone-Transfer Agent.

A facile synthesis of a binuclear AgI complex 2 of a bis(carbone) ligand L and its application as a carbone-transfer agent for the generation of other transition-metal complexes of AuI (3), NiII (4), and PdII (5) is presented. Complex 2 was synthesized through multiple synthetic routes under mild reaction conditions using the tetracationic [LH4][OTf·Cl]2 precursor salt, the dicationic [LH2][OTf]2 ylide salt, and the free ligand L. The first two synthesis routes require no prior isolation of the air-, moisture-, and temperature-sensitive free ligand L, thus affording complex 2 with high yield and purity. Multinuclear NMR techniques, high-resolution mass spectrometry, and single-crystal X-ray diffraction analysis confirmed the identity of complex 2 as a binuclear AgI complex of L with a molecular formula of [L2Ag2][OTf]2 and a 16-membered-ring metallomacrocyclic structure. During the transmetalation reaction with AuI, the binuclear nature of complex 2 remains intact to give analogous complex 3 ([L2Au2][OTf]2). However, the dimeric structure was disrupted upon the carbone-transfer reaction with NiII and PdII, yielding mononuclear C-N-C pincer-type complexes 4 ([LNiCl][OTf]) and 5 ([LPdCl][OTf]), respectively. These results demonstrated the versatile use of complex 2 as a carbone-transfer agent to other transition metals regardless of the type or size of the metals or the geometry they prefer.