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To monitor the reaction between Ce4+ ion and Cl– ion at the electron level, an electrochemical experiment was designed in this work. Herein, the intermediate and final products that may be produced during the redox reaction are directly tracked by using cyclic voltammetry, and the influences of Ce4+ ion concentration, temperature and F– ion on the reduction peak potential of Ce4+ ion were investigated. The results show that Ce4+ ion reacts with Cl– ion through an irreversible reaction without any intermediate products, and the rate-determining step of the reaction is diffusion during the electrode reaction. The effects of temperature (20–40 °C) and Ce4+ ion concentration (0.04–0.12 mol/L) on the reduction peak potential of Ce4+ ion can be ignored, but the higher the molar ratio of F– to Ce4+ (0–3 mol/mol), the more easily the reduction of Ce4+ ion to Ce3+ ion occurs. Additionally, the Ce4+ ions are preferentially reduced by thiourea when thiourea is added in the HCl solution, and thiourea inhibits the oxidation of Cl– ions to Cl2 by forming a complex with Cl– ions. This work provides a theoretical basis for the role of thiourea in inhibiting Cl2 production and offers a new way to find new reductants.

Rare earth elements (REE) are strategic resources and the recycling of REE in alternative resources is urgent and gets increasingly attention. However, the separation of REE in these alternative resources is still a challenge due to the low concentration of REE and multi coexisted ions in acidic system. In this study, the species distribution of REE within the pH 0 to 8.0 was calculated. The SBA-15 originated from coal fly ash was modified by two steps with (3-Aminopropyl) triethoxysilane (APTES) and diethylenetriaminepentaacetic dianhydride (DTPADA) to obtain DTPADA-SBA-15 adsorbent, which was applied to the selective adsorption of REE. The results showed that DTPADA-SBA-15 possessed excellent adsorption performance on the selective adsorption of REE, including Eu, Gd, Tb, Nd and Sm, in acidic solution (pH 2) with multi competing ions. The FT-IR and Zeta potential characterization verified that the chemical adsorption through the coordination of O in DTPADA-SBA-15 with REE was dominant at lower pH value. The study of adsorption kinetics indicated that the adsorption of rare earth metal ions followed pseudo-second-order kinetic, of which the adsorption process followed the Langmuir isotherm model.

The development of uranyl ion detection technology has exhibited its significance in public security and environmental fields for the radioactivity and chemical toxicity of uranyl ion. The WHO standard of uranyl ion makes it necessary to develop highly sensitive uranyl rapid warning system in drinking water monitoring. Herein, a visualized rapid warning system for trace uranyl ion is carried out based on electrochemiluminescence (ECL) imaging technology to give an ultra-low limit of detection (LOD) and high selectivity. Amidoxime, a bi-functional group with both uranyl ion capturing and co-reactive functions, is modified on a conjugated polymer backbone with strong ECL signal to be prepared into three-in-one polymer nanoparticles (PNPs) with self-enhanced ECL property. The captured uranyl ion can enhance the ECL signal of PNPs via resonance energy transfer process to give the LOD as 0.5 ng/L, which is much lower than the known luminescent uranyl sensors. Furthermore, ECL imaging technology is introduced into realizing visualized uranyl rapid warning, and can be successfully applied on natural water samples. This study provides a novel strategy for uranyl rapid warning, and shows its potential meaning in public security and environmental fields.

Bastnaesite is an important rare earth mineral and is usually beneficiated by flotation. Sodium silicate is commonly used to depress calcium-bearing gangue minerals, however it can also depress bastnaesite when Ca2+ ions exist in the pulp. In this study, the effect of Ca2+ ions and sodium silicate individually or in combination on bastnaesite flotation was studied through micro-flotation, zeta potential, fluorescence spectroscopy and X-ray photoelectron spectroscopy (XPS) measurements. Micro-flotation results show that the combination of Ca2+ ions and sodium silicate depresses bastnaesite more severely due to their synergistic effect. Zeta potential results show that the combination renders the surface potential of bastnaesite negatively shifted more significantly. Fluorescence spectroscopy shows that the combination decreases the surface hydrophobicity of bastnaesite more severely. XPS shows that the combination increases the adsorption of sodium silicate on bastnaesite by forming hydrophilic Ca-SiO3 precipitate, which causes more serious depression on bastnaesite flotation.

In this work, six energetic complexes were prepared and used as promoters for the hypergolic reaction of 1-ethyl-3-methylimidazolium cyanoborohydride [EMIM][BH3CN] and 90% H2O2. The structures of these compounds were studied by FT-IR spectroscopy, powder XRD, and single crystal X-ray diffraction. The results revealed that all the compounds were iso-structural and each metal centre was coordinated with four organic ligands and two counter ions. The decomposition temperatures of these compounds ranged from 169.6-255.9 °C. After adding 10 wt.% of prepared complexes to an ionic liquid, [EMIM][BH3CN], the shortest ignition delay time achieved was 94 ms. Moreover, the formed homogenous catalytic fuels had similar densities, thermal stabilities, as well as specific impulses similar to that of pure [EMIM][BH3CN]. The simple preparation method, excellent yield, as well as high performance of these compounds make them promising promoters for use in green hypergolic bipropellants.

Aims Copper ion is widespread in wastewater and threatens the condition and human health. Micro-organisms have unique advantages to remove heavy-metal ions from water, but are rarely reported in the removal of copper ion. This aims to develop micro-organisms that can remove copper ion in water, characterize their properties and analyse their potential application in practice. Methods and Results Sewage sludge was used as the source to isolate wild bacteria that can remove copper ion in water. The most efficient strain was screened out from 23 obtained isolates, identified as Bacillus pseudomycoides and coded as C6. The properties of C6 in the removal of copper ion in water were investigated in the aspects of reaction conditions, reaction groups, reaction dynamic and the application in oat planting. The reaction at pH 7 within 10 min yielded the highest removal rate of copper ion, 83%. The presence of lead ion in the reaction system could promote the removal rate of copper ion. Carboxyl groups and amidogen of C6 biomass were mainly involved in the removal of copper ion. The removal of copper ion was in accord with single-layer adsorption and Langmuir adsorption isotherm model. In application, C6 biomass reduced the copper content in the oat seedlings grown in copper ion containing water by more than seven times. Conclusions B. pseudomycoides C6 can efficiently remove copper ion in water and inhibit it from entering plants. Significance and Impact of Study This is the first time to report the capability of B. pseudomycoides to remove copper ion in water, which is also more efficient than the currently reported chemical and biological methods.

Owing to the rising concern of global warming, lithium-ion batteries have gained immense attention over the past few years for the development of highly efficient electrochemical energy conversion and storage systems. In this study, alpha-phase VOPO4·2H2O with nanosheet morphology was prepared via a facile hydrothermal method for application in high-performance lithium-ion batteries. The X-ray diffraction and scanning electron microscopy (SEM) analyses indicated that the obtained sample had an alpha-2 (αII) phase, and the nanosheet morphology of the sample was confirmed using SEM. The lithium-ion battery with VOPO4·2H2O as the anode exhibited excellent long-term cycle life and a high capacity of 256.7 mAh g−1 at room temperature. Prelithiation effectively improved the specific capacity of pristine VOPO4·2H2O. The underlying electrochemical mechanisms were investigated by carrying out AC impedance, rate capability, and other instrumental analyses.

Solid-state NMR (ssNMR) spectroscopy is a powerful technique for characterizing the surface sites of solid acids and organic intermediates formed during the acid catalyzed reaction. As a very useful probe molecule, ammonia is often utilized to determine the density of solid acids’ surface sites by ssNMR spectroscopy. The present mini-review summarizes some of the latest research developments on the quantitative characterization of the acid sites and carbenium ions during the zeolite catalytic reaction by ammonia probe-assisted ssNMR spectroscopy.

A once overlooked source of electrolyte degradation incurred by dissolved manganese (II) species in lithium-ion batteries has been identified recently. In order to deactivate the catalytic activity of such manganese (II) ion, 1-aza-12-crown-4-ether (A12C4) with cavity size well matched manganese (II) ion is used in this work as electrolyte additive. Theoretical and experimental results show that stable complex forms between A12C4 and manganese (II) ions in the electrolyte, which does not affect the solvation of Li ions. The strong binding effect of A12C4 additive reduces the charge density of manganese (II) ion and inhibits its destruction of the PF6− structure in the electrolyte, leading to greatly improved thermal stability of manganese (II) ions-containing electrolyte. In addition to bulk electrolyte, A12C4 additive also shows capability in preventing Mn2+ from degrading SEI on graphite surface. Such bulk and interphasial stability introduced by A12C4 leads to significantly improved cycling performance of LIBs.

It is highly important to design and develop appropriate insoluble anodes for industrial Cu electroplating to lower the amount of organic additives that this process consumes. Conventionally, this rapid consumption of additives (e.g., brighteners, suppressors, or levelers) is known to be due to the active radical species (e.g., OH) formed during oxygen evolution. In this study, we found that trace amounts of chloride ions present in the electroplating bath are the source of the active chlorine species that accelerate the breakdown at the insoluble anode. A sacrificial, perfluorinated polymer coating effectively decreased the emission of active chlorine species from the electrode, thereby lowering the consumption of the brightener. This study reveals that the suppression of chlorine evolution at the anode can be an effective approach for decreasing brightener consumption during Cu electrodeposition.

Mixed-anion compounds, in which multiple anions such as O2−, N3−, and H− are contained in the same compound, have recently attracted attention. Because mixed-anion compounds have a unique crystal s...

This work is devoted to the study of the features of ismorphism in compounds of the Ca-Na-Bi-P-O-F system, which have a crystalline structure of the mineral apatite, as well as its effect on the biocompatibility of substances in relation to human cells in an in vitro model. The Ca10-2xBixNax(PO4)6F2 system (x = 0,1,2,3,4,5) is characterized by continuous isomorphism, which follows from the minimum deviations of the unit cell parameters from the Vegard and Rotgers rules. The refinement of the crystal structure showed that the cations are unevenly distributed between the 4f and 6h positions of the crystal structure of apatite: bismuth ions are predominantly localized in the 6h position, while sodium ions are concentrated in the 4f position. The standard MTT test showed the biocompatibility of compounds with x = 1,2,3,4, and at x = 1 an anomaly was found in the form of an increased relative cell growth rate. The paper discusses the possible crystal-chemical and morphological reasons for this phenomenon.

The binary In ? Li system is a promising Li-ion battery anode material as well as a part of the important ternary Ge ? In ? Li system. The thermodynamic descriptions of metallic systems are widely used to retrieve information necessary for alloy applications. In this work, a thermodynamic model of a binary indium ? lithium system prepared by the Calphad approach is proposed. The liquid phase was described by an associate model, and the solid phases determined by the ab-initio calculation were included in the thermodynamic modeling. The obtained set of self-consistent thermodynamic parameters well reproduces the available experimental data and enables further calculations of multi-component systems. A good agreement between the calculations and the available experimental data was found. The proposed model can be used for further descriptions of ternary systems.

One-step solid-state method has been used to synthesize Li2ZnTi3O8 (LZTO) co-doped by Mo6+ and P5+ ions (LZM7TP3O). The structure stability, pore size and specific surface area have been improved via the strategy. In addition, LZM7TP3O has high ionic and electronic conductivities, and small transfer resistance. So, co-doping strategy tremendously enhances the electrochemical performance of LZM7TP3O in the wide temperature range. Cycling for 600 cycles at 25 °C, no capacity fading occurs for LZM7TP3O based on the 2nd cycle at 1 A g-1. 180.5 mAh g-1 is still kept at 3 A g-1 for the 120th cycle. Cycling for 100 cycles at 55 °C, no capacity decay occurs for LZM7TP3O relative to the 2nd cycle at 1 A g-1. At 0 °C, cycling for 1000 cycles at 0.5 A g-1, no capacity loses relative to the 2nd cycle. At 0.5 C, the initial discharge specific capacity of the LiNi0.5Mn1.5O4/LZM7TP3O full cell can reach 214.3 mAh g-1 in 2-4.55 V, when LZM7TP3O is used as the anode of the full cell. Moreover, the full cell can power red, green and blue light emitting diode (LED) bubbles. The results indicate that LZM7TP3O is an appealing anode of lithium-ion batteries.

Aqueous lithium/magnesium ion battery was assembled with Li0.21MnO2·H2O (LMO) as the cathode and VO2 as the anode.

We design a simple and cost-effective strategy to construct a large–scalable nitrogen-rich sulfur-doped porous carbon material as a high-performance anode material for lithium-ion batteries.

This article highlights the design and synthesis of Schiff base of veratraldehyde based organosilatranes and organosilocanes (3a-3c) and these were meticulously characterized with the aid of NMR (1H and 13C) and mass spectroscopic techniques. Moreover, the compound VBS (3a) was fabricated over silica nanoparticles by one-pot method which was enrichly authenticated by IR, XRD, EDX, TGA, and FE-SEM analysis. The colorimetric and fluorimetric detection of VBS and its hybrid silica nanoparticles (V-NPs) revealed their significant sensorial ability towards Cu2+ and Fe3+ over other relevant competitive metal ions. Interestingly, the binding of sensor VBS and V-NPs with Cu2+ and Fe3+ ions manifested an instant color change from yellow to light green and colorless, respectively in day light which is detectable by “naked-eye” and fluorescent turn-off response in UV-light. The results demonstrated that the organic-inorganic nanohybrids exhibited better sensitivity, greater affinity and lower limit of detection leading to better response time than the parent VBS towards Cu2+ and Fe3+ ions. The computational analysis using DFT approach was annotated to get an insight into the complexation mode of VBS with Cu2+ ion and Fe3+ ion. In addition to this, anti-oxidant properties were also investigated for compounds 3a-3c. Altogether, these findings paved the way for the design and synthesis of dual metal ion sensor.

A novel organic receptor based on isocyanate ions was developed and converted into its organic nanoparticles. The organic nanoparticles (ONPs) developed were of size 15–20 nm characterized via DLS and TEM. A recognition study was carried out to examine the response of ONPs towards different TBA salts of anions. Electrochemical studies were performed and from CV and DPV plots it was observed that among all the tested anions, ClO4- ions showed selective response. To confirm the selectivity, titration studies were carried out and a calibration curve was drawn which depicts the high sensitivity of ONPs towards ClO4- ions and 3 sigma method was utilized for calculating the detection limit and was obtained to be 7.9 nM. The real time applications of the synthesized sensor were explored and the accuracy of the analysis was found to be greater than 95%.

This study proposes the comparison of raw and alkali metal ion free banana peel as potential adsorbent for the removal of Hg2+ ions from aqueous solution. The alkali metal ions from banana peel was removed by protonation process with the help of HCl as protonation agent. Batch adsorption investigations were adopted in order to standardise the batch variables. The equilibrium data and kinetic data tend to fit well with Langmuir and pseudo second order kinetic models. The maximum loading capacity of the adsorbents was found to be 46.8 and 52.2 mg g−1 respectively. Desorption of Hg2+ ions was successfully achieved with the protonating agent used in this study. These investigations suggest that the protonation step enhances the removal efficiency of Hg2+ ions from aqueous solutions.

The multiple probable oxidation states of actinide elements can lead to their molecular anions to result in complicated yield patterns from a Cs+ sputter ion source. For actinides AMS, two methods can be practiced in order to concentrate the yields into just one or two anion species. The present common practice has been to avoid excessive oxygen reactions in the sputter targets, so that the mono-oxide anions can be produced with good or applicable ionization efficiencies. However, this method requires the typical 860-type Cs+ sputter ion sources to be operated with relatively high Cs+ fluxes, a condition that not all such sources in use can be operated with lasting stability. On the contrary, with low Cs+ fluxes, good or applicable ionization efficiencies can also be achieved for producing element-specific polyatomic oxide, oxyfluoride, or fluoride anions of actinides, if the sputter targets are aided with dominantly oxidizing or fluorinating matrices. This paper describes a systematic study of such phenomena using ZnO and FeF3 to form the respective oxidizing and fluorinating matrices. It was found that using the chosen set of polyatomic fluoride anions and the FeOxHy + FeF3 sputter targets, not only all rare actinides could be measured with low backgrounds matching those using mono-oxides, but also with the available ionization efficiencies fully utilized within a shorter time. A few additional merits are also noted.

A series of trinuclear complexes, [MnII2YIII(L)2(HL)2(NO3)3][YIII(NO3)5]·7H2O (1'), [MnII2GdIII(HL)4(NO3)4]2[MnII2GdIII(L)(HL)3(NO3)4][GdIII(NO3)5]4·2(o-Xy)·12H2O (2') and [MnII3(L)(HL)2(NO3)4](NO3)·1.25(p-Xy) (3'), were synthesized by using a β-diketone ligand HL (HL = 1,3-bis(pyridin-2-yl)propane-1,3-dione). X-ray structural analyses revealed each complex has a trinuclear core with a Mn(II)-M-Mn(II) arrangement (M = YII (1), GdIII (2), and MnII (3)). In 1' with a diamagnetic Y(III) ion, negligible antiferromagnetic interactions between terminal Mn(II) ions are operative. On the other hand, 2' shows ferromagnetic interactions between Mn(II) and Gd(III) ions, affording spin ground state of ST = 17/2. The homometallic Mn(II)3 complex of 3' has ST = 5/2 spin ground state resulting from the antiferromagnetic interactions between neighboring Mn(II) ions. Maximum magnetic entropy change (-ΔSm) of 1' - 3' was estimated to be 12.3, 24.8, and 8.0 J kg-1 K-1, respectively.

The fluorescent probe fluorescein hydrazide was designed for mercury sensing by fluorescence assay. The probe was color less and non-fluorescent in the absence of Hg2+ ions and highly fluorescent and green colored in the presence of Hg2+ ions. The probe is highly specific to Hg2+ ions under pH 12 buffer conditions. No other ions interfered during fuolrimetric analysis of the Hg2+ ions. The fluorescence assay was done at excitation wavelength of 502 nm and emission wavelength at 520 nm. The emission wavelength measured at 520 nm is proportional to the concentration of Hg2+ ions in the assay solution. The developed fluorescence assay protocol based on fluorescein hydrazide as fluorescent probe was used for mercury speciation in lead acid battery samples successfully.

Since the breakthrough findings of Goodenough et al. in 1997, extensive research was carried out on olivine-type LiMPO4 (M: Transition metal) cathode materials for lithium ion batteries. This study reports the synthesis of five compounds LiFe1-xMnxPO4 (x = 0, 0.4, 0.6, 0.65, and 1) using sol–gel method at 800 °C. The crystal structure and the electrochemical properties of LiFe1-xMnxPO4 versus Li+/ Li were investigated. LiFe1-xMnxPO4 materials crystallize in the orthorhombic system with Pnma as space group. Moreover, a slight increase in the cell volume was noticed with the increasing amounts of Mn due to its large ionic radii (where Fe2+ ions (0.78 A) and Mn2+ ions (0.80 A). LiFe0.4Mn0.6PO4 shows the best electrochemical performances delivering a reversible discharge capacity of 110 mAh g−1 for 10 cycles at C/20 although no effective carbon coating was performed on the particles of this phosphate.

Symmetrical non-aqueous organic redox flow batteries are highly promising systems for electrochemical energy storage. A higher solubility and energy density of a previously described robust ROM was obtained by straightforward nitration of its core.

ZnTiO3 and ZnTiO3-CeO2 microspheres with a particle size about 100~300 nm was synthesized by a simple solvothermal process following by a calcination for the first time. The result indicates that the CeO2 modification does not alter the morphology of modification. The ZnTiO3-CeO2 (0, 3%, 6%, and 9 wt%) show an initial charge (discharge) capacity of 171.01(253.2), 204.6(507.5), 213.4(451.6) and 126.2(367.2) mAh g-1 at 500 mA g−1, respectively. After 500 cycles, the corresponding charge (discharge) capacities are 191.1(192.3), 298.7(300.3), 322.4(328.5) and 211.2(212.3) mAh g-1, respectively. Obviously, the charge (discharge) capacities of ZnTiO3-CeO2 composites are superior to the pristine ZTO, which demonstrates that the Li storage performance of the CeO2 modified ZTO electrodes is improved. The CeO2 shell provide a well electric contact between ZnTiO3 andCeO2, and then decrease charge transfer resistance and facilitate the charge transportation of ZnTiO3-CeO2 composite. In addition, the formed phase interfaces between CeO2 and ZnTiO3 may provide more active sites of electrochemical reaction, and then improve the reversibility of Li-ion intercalation and decrease the electrochemical polarization during cycling, especially at high current densities. Therefore, such ZnTiO3-CeO2 microspheres can be regarded as hopeful candidates of anode materials for Li-ion battery.

Organic cations are essential components of locally concentrated ionic liquid electrolytes (LCILEs), but receive little attention. Herein, we demonstrate their significant influence on the electrochemical performance of lithium metal batteries via a comparison study of two LCILEs employing either 1‑butyl‑1-methylpyrrolidinium cation (Pyr14+) or 1-ethyl-3-methylimidazolium cation (Emim+). It is demonstrated that the structure of the organic cation in LCILEs has only a limited effect on the Li+- bis(fluorosulfonyl)imide anion (FSI−) coordination. Nonetheless, the coordination of FSI− with the organic cations is different. The less coordination of FSI− to Emim+ than to Pyr14+ results in the lower viscosity and faster Li+ transport in the Emim+-based electrolyte (EmiBE) than the Pyr14+-based electrolyte (PyrBE). Additionally, the chemical composition of the solid-electrolyte interphase (SEI) formed on lithium metal is affected by the organic cations. A more stable SEI growing in the presence of Emim+ leads to a higher lithium plating/stripping Coulombic efficiency (99.2%). As a result, Li/EmiBE/LiNi0.8Mn0.1Co0.1O2 cells exhibit a capacity of 185 mAh g−1 at 1C discharge (2 mA cm−2) and capacity retention of 96% after 200 cycles. Under the same conditions, PyrBE-based cells show only 34 mAh g−1 capacity with 39.6% retention.

The fluorescence intensity ratio (FIR) technique is widely adopted in thermometric phosphor materials, but the improvement of relative sensitivity is normally limited by the fixed energy gap between two thermally-couped emitting levels of luminescent ions. Herein, LnAl3(BO3)4:Cr3+ (LnAB:Cr3+, Ln = Gd, Y, Lu) phosphors are found to simultaneously show 4T2 and 2E emissions of Cr3+, and their FIR is sensitive to temperature and suitable for fluorescence thermometric applications. Moreover, the energy gap between 4T2 and 2E levels of Cr3+ is tunable and the relative sensitivity can be greatly improved by modifying the host composition. Structural analysis and spectroscopic data confirm that the enhanced crystal-field of Cr3+/Al3+ sites caused by incorporating smaller Ln3+ ions into the host contributes to the improvement of relative sensitivity. The work would provide new insights for the development of novel FIR thermometric materials with high-sensitivity.

A series of solid-solution phosphates germanates Ca8+0.5xZnEu(PO4)7–x(GeO4)x (x = 0, 0.2, 0,4, 0.6, 0.8, 1, 1.2, 1.4) with β-Ca3(PO4)2-type structure have been synthesized by solid-state reactions. The limit of existence of a single-phase solid solution has been determined by X-ray diffraction patterns, and it was found at x = 1. The heterovalent substitution tetrahedral [PO4]3– → [GeO4]4– substitution requires a charge compensation according to the scheme: [PO4]3– + ½ □  [GeO4]4– + ½ Ca2+. The additional amount of Ca2+ ions in the crystal structure was detected in the M4 site during Rietveld refinement. It was shown that in compounds with the β-TCP-type the charge balancing is not provided by the randomly distributed oxygen vacancies, but only due to the partial occupancy of the M4 site. The presence of Ca2+ in the M4 site leads to polar structure with the space group R3c, and it was confirmed by the SHG test for all single-phase samples. It was shown, that Ge4+ ion occupies preferably T3 site in structure, which is connected through common oxygen with cationic M1-M5 sites. The analysis of the similarity of previously reported Ca9La(GeO4)0.75(PO4)6 compound reveals an unexpectedly high value. The same evaluation of the structure similarity for studied compound Ca8.1EuZn(PO4)6.8(GeO4)0.2 in the present work with the initial model gives a very small value which indicates a good match between initial and under consideration structures. Luminescent properties of Eu3+ were investigated in the point of view of crystal structure and anionic substitution. The integral intensity was increased linearly with [PO4]3– → [GeO4]4– substitution. It can be concluded that anionic substitution on Ge4+ can improve luminescence characteristics. The present study includes new data on the anionic substitution based on accurate crystal structure refinement.

N,Nʹ-dialkylimidazolium-ion liquids is one of the important ionic liquids with a wide range of application as conductive electrolyte and in electrochemistry. The modified electrodes create a new view in fabrication of electroanalytical sensors. Many modifiers have beeen suggested for modification of electroanalytical sensor since many years ago. Over these years, ionic liquids and especially room temperature ionic liquids have attracted more attention due to their wide range of electrochemical windows and high electrical conductivity. N,Nʹ-dialkylimidazolium-ion liquids are one of the main important ionic liquids suggested for modification of bare electrodes and especially carbon paste electrodes. Although many review articles have reported onthe use of ionic liquids in electrochemical sensors, no review article has been specifically introduced so far on the review of the advantages of N,Nʹ-dialkylimidazolium ionic liquid. Therefore, in this review paper we focused on the introduction of recent advantages of N,Nʹ-dialkyl imidazolium ionic liquid in electrochemistry.

We recently reported the synthesis of three high-silica (Si/Al ∼ 10) zeolites with new framework structures (i.e., PST-21, PST-22, and PST-30) via an excess fluoride approach which uses synthesis mixtures with HF/OSDAn+ = 2/n (n = 1 or 2). However, the use of toxic and corrosive fluoride ions should be avoided for the green manufacturing of zeolites. Here we examine the structure-directing abilities of eight diazolium-based mono- and dications in hydroxide media which could crystallize PST-21, PST-22, or PST-30 under excess fluoride conditions. Among them, 1,1′-(1,4-butanediyl)bis(2,4-dimethyl-1H-pyrazol-2-ium) (14DMP-C42+) and 1,1′-(1,4-butanediyl)bis(2,5-dimethyl-1H-pyrazol-2-ium) ions were found to direct the synthesis of PST-22 and PST-30 in the presence of Na+ ions, respectively. Powder X-ray diffraction and Rietveld analyses of as-made PST-22 reveal that while the pyrazolium moieties in 14DMP-C42+ are located near the center of t-pww cages, the tetramethylene chain runs through a 10-ring window connecting two t-pww cages. The proton forms of PST-22 and PST-30 synthesized here exhibit better performance in 1-butene skeletal isomerization than H-ferrierite, one of the most selective catalysts for this reaction.

Hypophosphite hybrid perovskites have recently received a widespread of attentions due to their diverse structural, magnetic, negative thermal expansion and photoluminescence behaviour. Herein, we report two new three-dimensional hybrid perovskites containing unusually large organic cations, pyrrolidinium and 2-hydroxyetylammonium. We report crystal structures of these new manganese-hypophosphite frameworks as well as their magnetic and optical properties. We also report magnetic and optical properties of two previously discovered analogues, dimethylammonium and imidazolium manganese hypophosphites. Both new compounds crystallize in a monoclinic structure, space group P21/n, with ordered organic cations at room temperature. Magnetic studies show that all studied compounds are examples of canted antiferromagnets but the weak ferromagnetic contribution and the ordering temperature are significantly modulated by type of organic cation located in the cavity of the framework. We discuss origin of this behaviour. Upon ultraviolet excitation, all compounds exhibit broadband photoluminescence associated with the 4T1g(G)→ 6A1g(S) transition of octahedrally coordinated Mn2+ ions. Position of the PL band depends on the type of organic cation, being the most blue-shifted for the imidazolium analogue (646 nm) and the most red-shifted for the pyrrolidinium counterpart (689 nm). The most interesting properties of the studied hypophosphites is, however, strong temperature dependence of the photoluminescence intensity, suggesting possible application of these compounds for non-contact optical thermometry.

In this study, a series of 1-alkyl-3-methylimidazolium ionic liquids with bis(nonafluorobutylsulfonyl)imide anion ([NNf2]-anion) was synthesized. Their physicochemical properties and surface behaviours were analysed and compared to the widely used 1-alkyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imides ([NTf2]-anion) ionic liquids. For the [NNf2]-ionic liquids, a dominating influence of the anion on physical properties such as thermal transitions, viscosity and polarity than the [NTf2]-IL was observed. With the high-precision drop shape analysis (HPDSA) approach static and dynamic wetting behaviours on both hydrophilic and hydrophobic substrates were characterised and compared to water and imidazolium ionic liquids with perfluoroalkyl-bearing cations. The [NNf2]-ionic liquids exhibited only minor differences of their static wetting properties, but showed noticeable differences of their dynamic wetting properties. It is shown that the wetting properties strongly depend on the degree and position of the fluorous side chain (for both in the cation and anion), but only slightly depend on the elongation of the alkyl side chain.

In this paper, two novel organic-inorganic hybrid supramolecule compounds {[Cu·L1’·H2O]·(α-Mo8O26)0.5}n 1 and compound {[Cu·L2’·H2O]·(α-Mo8O26)0.5}n 2 have been synthesized [L1’ = 1, 3-bis (4-carboxylpyridine) propane dibromide, L2’ = 1, 4-bis (4-carboxylpyridine) butane dibromide]. Compounds 1 and 2 have been expressly confirmed by PXRD, IR, X-ray single crystal diffraction and TG. Last, the study found that compounds 1 and 2 have obvious adsorption effects on MB and RhB organic dyes, and compound 2 has high adsorption capacity for MB.

The key to developing new infrared nonlinear optical (NLO) materials is balancing second-order nonlinear optical effects and the laser-induced damage threshold (LIDT). In this paper, a new polymorph of HgBr2 (P212121) was synthesized by a "halogen-ion-induced effect" in solution, which features a crystal structure different from that of the original phase (Cmc21) and exhibits better NLO properties. Its powders show a strong SHG effect (9 × KDP), a high LIDT (30 × AgGaS2), a wide infrared transparent range, and stability in air, making it a prospective NLO material in the IR region. In addition, the above excellent NLO characteristics are well illustrated in DFT theoretical calculations. More importantly, experimental results show that the new infrared NLO polymorph with excellent comprehensive properties could be controllably obtained by using the halogen-ion-induced strategy.

Among the solid electrolytes studied for all-solid-state sodium batteries (ASSBs), Na3SbS4 (NAS) appears particularly promising due to its unique combination of high ionic conductivity and compatib...

In this article, we propose high-performance colorimetric detection of Hg+2 using silver nanoprisms. The spherical and triangular AgNPs were synthesized using varied concentration of NaBH4. Pristine AgNPs without any further modification were used for the detection of various metal ions including Hg2+, Pb2+, Cl−, Cd2+, Co2+, Cu2+, Ba2+, Pb2+, Cr3+, Cr2O2−7 , Fe2+, Fe3+ etc. AgNPs were not only selective in detecting the ions of Cl− and Hg+2 ions but also highly sensitive. Minimum detection limit was observed to be as low as 10−7 ppm for both Hg+2 and Cl−. Water samples collected from various locations detected for the presence of various heavy metals. Silver nanoprisms owing to their surface plasmon resonance exhibit highly selective tendency towards detection against Hg+2.

Originating from “rocking‐chair concept”, lithium‐ion batteries (LIBs) have become one of the most important electrochemical energy storage technologies, which have largely impacted our daily life. The utilization of electrolyte additives in small quantities (≤5% by wt or vol) has been long viewed as an economical and efficient approach to regulate the properties of electrolyte and electrode–electrolyte interphases and consequently improve the cycling performance of LIBs. Among all the kinds of electrolyte additives, sulfur‐containing compounds have gained significant attention due to their unique features in building stable electrode–electrolyte interphases and protect battery cells from overcharging. In this work, advances and progresses of sulfur‐containing additives used in LIBs are overviewed, with special attention paid to the working mechanisms of these electrolyte additives. Particularly, four representative sulfur‐containing compounds (i.e., 1,3‐propane sultone, prop‐1‐ene‐1,3‐sultone, 1,3,2‐dioxathiolane‐2,2‐dioxide, and ethylene sulfite) are comparatively discussed concerning their impact on electrode–electrolyte interphases and cell performances. Future work on the development of sulfur‐containing compounds as functional electrolyte additives is also provided. The present review is anticipated to be not only a base document to access the status quo in this research domain but also a guideline to select specialized additives and electrolytes for practical applications.

The work discusses about the synthesis of indium-alizarin red S complex followed by its application toward the sensing of F¯ ion. At first, the interaction between indium and alizarin red S dye was studied at three different pH medium, pH 4, 7 and 9, of which pH 7 gave the best result. The indium-alizarin red S complex so obtained was then utilized for the ratiometric sensing of fluoride ion using absorption spectroscopy with variation of temperature. The lowest limit of detection (0.040 mM) was obtained at 313 K. The mechanism for the sensing of F¯ ion was then investigated using isothermal titration calorimetry. The endothermic nature of the interaction between F¯ ion with indium-alizarin red S complex shows temperature dependence on the sensing experiment. At the end, the utility of the technique toward natural sample was also examined. The present work reports a simple, rapid and efficient detection of fluoride anion in environmental water samples.

A synthetic method is described to produce some chromenone-pyrazole derivatives through a one-pot multicomponent reaction using SrFe12O19 as a magnetic catalyst. This method provides quite a few merits, including the use of an effective and easy separable nanocatalyst, high yields of products, short reaction time, and easy work-up. Two of the products showed fluorescence properties, which have detected mercury ions without any interference with other ions. They can detect a tiny amount of mercury ions, which were comparable with other chemosensors. The detection limit is 4 × 10-7 and 3 × 10-8 M, respectively, for the compound I and II, respectively, which were considered very low amounts. The effect of mercury on health and environmental pollution is essential in medical science.

An O3 type Li0.6[Li0.2Mn0.8]O2 lithium-rich material has a high reversible capacity due to the synergistic oxidation and reduction of anion and cation. However, the anion oxidation reaction that compensates the charge leads to a partial release of oxygen and the collapse of the structure inevitably. Here, we improve the structural stability of Li0.6[Li0.2Mn0.8]O2 by simultaneously introducing Al ions and B ions. Al ions and B ions randomly occupy octahedral and tetrahedral positions, hindering the migration of Mn ions and expanding the unit cell, resulting in a stable structure and promoting Li+ migration. The co-doped sample has better electrochemical performance than the bare material, and the capacity retention increases from 62.48% to 82.48% after 80 cycles at 0.1C rate, and still provides a capacity of 226 mAh g−1 between 2 and 4.8 V.

Single-molecule magnets (SMMs) are expected to be promising candidates for the applications of high-density information storage materials and quantum information processing. Lanthanide SMMs have attracted considerable interest in recent years due to their excellent performance. It has always been interesting but not straightforward to study the relaxation and blocking mechanisms by embedding 3d ions into 4f SMMs. Here we report a family of air-stable 3d-4f ion-pair compounds, YFe (1), DyCr (2), DyFe (3), DyCo (4), and Dy0.04Y0.96Fe (5), composed of pentagonal bipyramidal (D5h) LnIII cations and transition metallocyanate anions. The ion-pair nature makes the dipole-dipole interactions almost the only component of the magnetic interactions that can be clarified and analytically resolved under proper approximation. Therefore, this family provides an intuitive opportunity to investigate the effects of 3d-4f and 4f-4f magnetic interactions on the behavior of site-resolved 4f SMMs. Dynamic magnetic measurements of 1 under a 4 kOe external field reveal slow magnetic relaxation originating from the isolated [FeIII]LS (S = 1/2) ions. Under zero dc field, compounds 2-5 show similar magnetic relaxation processes coming from the separated pentagonal bipyramidal (D5h) DyIII ions with high Orbach barriers of 592(5), 596(4), 595(3), and 606(4) K, respectively. Comparatively, both compounds 3 and 5 exhibit two distinct relaxation processes, respectively from the [FeIII]LS and DyIII [Ueff = 596(4) K for 3 and 610(7) K for 5] ions, under a 4 kOe dc field. The dipolar interactions between the neighboring TMIII (TM = transition metal, CrIII or [FeIII]LS) and DyIII ions were revealed to have little effect on the thermal relaxation in compounds 2, 3, and 5, or the coexistence of the two separate relaxation processes in compounds 3 and 5 under a 4 kOe dc field, but they significantly affect the quantum tunneling of magnetization and the magnetic hysteresis behavior of 2 and 3 at low temperatures compared to those of 4.

Nowadays, numerous studies have focused on the newly developed technologies for the thorough removal of tetracyclines (TCs). The efficient removal of trace-amount pollutants requires the development of improved materials with higher adsorption capacity and increased adsorption selectivity. Zn(II)-mediated chitosan nonwoven fabric (Zn-CSNW) adsorbent with coordination capability was explored for the effective and selective removal of TC. The adsorption of TC to Zn-CSNW could reach equilibrium in about 30 min with a maximum adsorption capacity of 195.9 mg/g. It exhibited high anti-interference performance for TC adsorption at low concentrations, with good regeneration and effective reuse. Except for citrate, organic materials similar in structure to TC or common ions in aqueous solutions did not show obvious competition for the adsorption of low concentrations of TC. Additionally, the inherent fluorescence of chitosan and the fluorescence sensitization effect of Zn2+ for TC enabled function of Zn-CSNW as an indicator of the adsorption of TC by changes in fluorescence color and intensity under UV light (365 nm). It can indicate the saturation state of the Zn-CSNW, which will bring convenience to the use of the adsorbent. The Zn(II)-mediated coordination interaction plays a vital role in both the selective recognition of TC and the fluorescence sensing of adsorption amount, demonstrating an affordable and effective strategy for the treatment of water containing low amounts of antibiotics.

The series of Gd3-xCexGa3Al2O12 nanopowders doped with different concentrations of Ce3+ ions were prepared by Pechini (sol-gel) and combustion methods. The structure and morphology of the powders were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. It was found that the synthesis method has a great impact on the morphology and, consequently, spectroscopic properties of the powders. Optical properties of the powders were examined using excitation, emission, and luminescence kinetic measurements. For all powders, persistent luminescence and emission decay processes were studied. The most intense luminescence was observed for the powder with 0.5 mol % of Ce3+ synthesized using the combustion method and 1 mol % in the case of the sol-gel sample. The longest and brightest persistent luminescence was observed for the powders doped with 0.1 mol % (combustion) and 0.2 mol % of Ce3+ ions (sol-gel). The thermoluminescence measurements were done for the powders prepared using different methods to understand the impact of the synthesis conditions on the number and depths of the traps involved in persistent luminescence. On the basis of spectroscopic measurements, the mechanism of persistent luminescence was constructed and discussed.

The ability of rhodamine cations to form cation-anionic associates with tetraphenylborate-anion in an aqueous solution has been studied. The thermodynamic values of the equilibrium association constants Kasт were determined spectrophotometrically. The values of a number of properties of dye molecules (surface area, effective volume, hydrophobicity index log P, standard enthalpy of hydration ΔНohydr) were calculated using the QSAR model. The possibility of dependence of the value of Kasт on these factors has been reviewed. It was shown that changes in lg Kasт in the series of rhodamine associates are consistent with changes in the parameters log P and ΔНohydr.

This study describes the evaluation of orange peel waste (OPW) to remove Co(II) ions from aqueous solutions. First, parameters such as pH, initial metal ion concentration, and contact time, which affect the adsorption efficiency, were studied. It was determined that the best initial Co(II) ion concentration, the adsorption contact and the solution pH were 125 mg/L, 100 min and 5.47, respectively. The surface properties of the orange peel were investigated using SEM, energy-dispersive spectroscopy, scanning and FTIR. The results showed that the isotherm data fit the Langmuir isotherm model, which corresponds to chemisorption and possible irreversibility of the process. The adsorption capacity for Co(II) was calculated to be 4.257, 4.491 and 5.128 mg/g at 298, 308 and 318 K, respectively. As a result of the adsorption kinetic data, it was determined that the adsorption of Co(II) metal ion conformed with the second-order kinetic model. Thermodynamic studies showed that the adsorption of Co(II) ion on orange peel is spontaneous and exothermic. It was shown that OPW can be used as an effective and alternative material in the removal of Co(II) ions from aqueous media due to its high capacity, easy availability and low cost.