Double Ion Research Articles

High-temperature piezoelectric properties and thermal stability of BF-BT-based ceramics by double A-site ion modification

High-temperature piezoelectric properties and thermal stability of BF-BT-based ceramics by double A-site ion modification

Overall Concept Design of 2.45 GHz ECR Ion Source with Tunable Magnetic Field

The design of the ECR ion source was made for an operating frequency of 2.45 GHz. The ion source is considered to be used for producing protons and double charged helium ions. The source construction as well as the separate components design are presented in the study. The operating modes include both ECR and microwave operating regimes. The extraction system with the beamforming was developed. The beam adjustment is implemented by the longitudinal shifting of the electrodes against the plasma electrode position. The performance of the 2.45 GHz waveguide line to provide the stable power injection into the plasma chamber is considered. The numerical simulation of the waveguide line components was made and optimised.

Effect of stress and irradiation fluence on latent track formation in swift heavy ion irradiation: A case study on TiO2

Swift Heavy Ions (SHI) irradiation, characterized by high kinetic energy ions, induces significant material/structural modification, e.g., latent track. However, the intricate interaction among various physics, i.e., mechanical stress, phase transition, and heat transfer, has been ignored in the continuum-based approaches in favor of simplicity. Here, we developed a two-dimensional coupled phase-field inelastic-thermal spike (PF-iTS) model to investigate the effect of thermal cross-talk, elastic energy, and irradiation fluence on latent track formation and size. The results reveal a shift in the critical electronic stopping energy and a reduced track radius under mechanical stress. Additionally, the study demonstrates the impact of thermal cross-talk between incidents, i.e., simultaneous and delayed double ion impacts, showing potential track merging and variations in track morphology.

Investigating the ions emitted by multiply charged ionic liquids from a porous electrospray ion source

A porous electrospray ion source was tested with three ionic liquids in order to investigate the effects of ionic liquid properties on the sizes of ion clusters emitted by purely ionic electrospray sources. Two of the ionic liquids, bis(1-ethyl-3-methylimidazolium) tetrathiocyanatocobaltate and 1,6-bis(3-methylimidazolium-1-yl)hexane bis(trifluoromethylsulfonyl)amide, were selected due to them having a dication or dianion, which were termed multiply charged ionic liquids due to them containing anions or cations with more than one charge within them. These were selected in order to investigate ionic clustering within electrospray ion emission and were compared against one of the most common ionic liquids, EMI-BF4. The current–voltage data showed that EMI-BF4 emitted similar levels of current to bis(1-ethyl-3-methylimidazolium) tetrathiocyanatocobaltate, even though the latter liquid had significantly lower conductivity and higher viscosity, suggesting an improvement in current speculated to be due to the extra charges contained by the ions. Time-of-flight and retarding potential analysis data are provided, showing all three liquids emitting ions comprising of monomers, dimers, trimers, and quadramers, with some of the 1,6-bis(3-methylimidazolium-1-yl)hexane bis(trifluoromethylsulfonyl)amide data showing heavier species emission. The data also suggested that the multiply charged ionic liquids produced ions that have two anions or cations attached, termed “double ions,” with these ions not been previously reported using porous electrospray sources. Furthermore, it was found that the dimers emitted by both of the multiply charged ionic liquids seemed to be more stable than EMI-BF4 dimers, providing insight into ion cluster formation.

Biomass Valorization through Catalytic Pyrolysis Using Metal-Impregnated Natural Zeolites: From Waste to Resources.

Catalytic biomass pyrolysis is one of the most promising routes for obtaining bio-sustainable products that replace petroleum derivatives. This study evaluates the production of aromatic compounds (benzene, toluene, and xylene (BTX)) from the catalytic pyrolysis of lignocellulosic biomass (Pinus radiata (PR) and Eucalyptus globulus (EG)). Chilean natural zeolite (NZ) was used as a catalyst for pyrolysis reactions, which was modified by double ion exchange (H2NZ) and transition metals impregnation (Cu5H2NZ and Ni5H2NZ). The catalysts were characterized by nitrogen adsorption, X-ray diffraction (XRD), ammonium programmed desorption (TPD-NH3), and scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDS). Analytical pyrolysis coupled with gas chromatography/mass spectrometry (Py-GC/MS) allowed us to study the influence of natural and modified zeolite catalysts on BTX production. XRD analysis confirmed the presence of metal oxides (CuO and NiO) in the zeolite framework, and SEM-EDS confirmed successful metal impregnation (6.20% for Cu5H2NZ and 6.97% for Ni5H2NZ). Py-GC/MS revealed a reduction in oxygenated compounds such as esters, ketones, and phenols, along with an increase in aromatic compounds in PR from 2.92% w/w (without catalyst) to 20.89% w/w with Ni5H2NZ at a biomass/catalyst ratio of 1/5, and in EG from 2.69% w/w (without catalyst) to 30.53% w/w with Ni5H2NZ at a biomass/catalyst ratio of 1/2.5. These increases can be attributed to acidic sites within the catalyst pores or on their surface, facilitating deoxygenation reactions such as dehydration, decarboxylation, decarbonylation, aldol condensation, and aromatization. Overall, this study demonstrated that the catalytic biomass pyrolysis process using Chilean natural zeolite modified with double ion exchange and impregnated with transition metals (Cu and Ni) could be highly advantageous for achieving significant conversion of oxygenated compounds into hydrocarbons and, consequently, improving the quality of the condensed pyrolysis vapors.

Resource utilization of sewage sludge as a nitrogen self-doped carbon quantum dot for specific detection of Fe3+ and Hg2+

With the widespread application of sewage biological treatment technology, a large amount of sewage sludge is generated during the sewage treatment process, which not only poses a threat to the environment but also results in wastage of C and N resources. In this study, the nitrogen self-doped fluorescent carbon dots (N-CDs) with an average particle size of 3.43 nm were synthesized green through a two-stage hydrothermal method. It was found that N-CDs can detect Fe3+ through internal filtration effect (IFE), with a linear detection range of 0–250 μM and a detection limit of 2.207 μM. Furthermore, N-CDs can also serve as a “turn off–on” probe for monitoring Hg2+, with a linear detection range of 2–10 μM and a detection limit of 0.989 μM. Interestingly, oxygen-containing groups were shown to be sensitive to Hg2+, which has been demonstrated for the first time. Moreover, the practical application of N-CDs as a double ion sensor in the detection of Fe3+ and Hg2+ has achieved good results for real power plant wastewater.

The Oscillatory Behaviour of Cu-ZSM-5 Catalysts for N2O Decomposition: Investigation of Cu Species by Complementary Techniques.

Copper-exchanged ZSM-5 (Cu-ZSM-5) is a promising catalyst thanks to the Cu redox pair. A particular feature of this material consists in the presence of spontaneous isothermal oscillations which take place during N2O decomposition reaction, depending on the operating conditions. In the present work, a set of five Cu-ZSM-5 catalysts was synthesised by three procedures and three different copper precursor concentrations: i) wet impregnation, ii) single ion exchange, and iii) double ion exchange. Catalytic tests revealed that the ion-exchanged samples exhibit a low catalytic activity and no oscillatory behaviour, except for the twice-exchanged sample which achieves an average N2O conversion of 26 % at 400 °C. Conversely, the impregnated samples reach higher levels of N2O conversion (66 % for Cu5ZSM5_WI and 72 % for Cu10ZSM5_WI) and demonstrate a similar oscillating pattern. Further investigations disclosed that the most active catalysts, characterised by the presence of oscillatory behaviour, have more abundant and easily reducible copper species (ICP, EDX and H2-TPR) which interact better with the zeolitic support (FT-IR). Catalytic tests under a long time on stream (TOS) suggest that either self-organised patterns or deterministic chaos can be achieved during the reaction, depending on the operating conditions, such as temperature and contact time.

High energy storage properties of (Nb0.5La0.5)4+ complex-ion modified (Ba0.85Ca0.15)(Zr0.10Ti0.90)O3 ceramics

In this work, a traditional solid-state method was adopted to prepare dense Ba[Formula: see text]Ca[Formula: see text][(Zr[Formula: see text]Ti[Formula: see text])[Formula: see text]–(Nb[Formula: see text]La[Formula: see text])x]O3(BCZT–xNL) lead-free relaxation ferroelectrics with excellent energy storage performance (ESP). Remarkably, a large breakdown field strength of BDS ([Formula: see text][Formula: see text]kV/cm) resulting from decreased grain size by double ions doping at the B-site was achieved in BCZT–xNL ceramics. Especially, the BCZT–0.12NL ceramic displays a good recoverable energy density ([Formula: see text]) of 3.1[Formula: see text]J/cm3, a high efficiency of 86.7% ([Formula: see text]) and a superior fatigue resistance, as well as a superior charge–discharge performance ([Formula: see text][Formula: see text]A/cm2, [Formula: see text][Formula: see text]MW/cm3, [Formula: see text][Formula: see text]J/cm3, [Formula: see text][Formula: see text]ns) and good thermal stability. Besides, upon NL doping, the FE to RFE phase transition results in a dielectric behavior traversing the relaxation phase ([Formula: see text]) accompanied by frequency dispersion, which is beneficial to improve ESP. The superior ESP in this work indicates that BCZT–0.12[Formula: see text]NL ceramics are a promising candidate used in energy storage capacitors.

Highly sensitive refractive index sensing based on nanostructured porous silicon interferometers

In this study, we present the experimental evidence demonstrating the utility of electrical double layer (EDL)-induced ion accumulation, using sodium (Na+) ion in water as model substances, on a negatively charged nanostructured surface, specifically thermally grown silicon dioxide (SiO2). This novel approach, termed Ion Surface Accumulation (ISA), aims to enhance the performance of nanostructured porous silicon (PSi) interferometers in optical refractometric applications. The experimental results show that the electrical double layer-induced ion surface accumulation (EDL-ISA) on oxidized PSi interferometers enables remarkable amplification of the interferometer output signal (the spectral interferogram), even when the bulk refractive index variation is below 10-3 RIU. This substantial signal enhancement translates into an increase in sensitivity of up to two orders of magnitude, facilitating the reliable measurement of refractive index variations with both a detection limit (DL) and resolution (R) as low as 10-4 RIU. This achievement elevates the performance of PSi interferometers in photonics and plasmonics-based refractive index platforms.

Self-Charging Aqueous Zn//COF Battery with UltraHigh Self-Charging Efficiency and Rate.

Self-charging zinc batteries that combine energy harvesting technology with batteries are candidates for reliable self-charging power systems. However, the lack of rational materials design results in unsatisfactory self-charging performance. Here, a covalent organic framework containing pyrene-4,5,9,10-tetraone groups (COF-PTO) is reported as a cathode material for aqueous self-charging zinc batteries. The ordered channel structure of the COF-PTO provides excellent capacity retention of 98% after 18 000 cycles at 10 A g-1 and ultra-fast ion transfer. To visually assess the self-charging performance, two parameters, namely self-charging efficiency (self-charging discharge capacity/galvanostatic discharge capacity, η) and average self-charging rate (total discharge capacity after cyclic self-charging/total cyclic self-charging time, ν), are proposed for performance evaluation. COF-PTO achieves an impressive η of 96.9% and an ν of 30mAhg-1 self-charge capacity per hour in 100 self-charging cycles, surpassing the previous reports. Mechanism studies reveal the co-insertion of Zn2+ and H+ double ions in COF-PTO of self-charging zinc batteries. In addition, the C═N and C═O (on the benzene) in COF-PTO are ortho structures to each other, which can easily form metal heterocycles with Zn ions, thereby driving the forward progress of the self-charging reaction and enhancing the self-charging performance.

Near-Zero Energy Consumption Capacitors by Controlling Inhomogeneous Polarization Configuration.

Taking into account the need for energy conservation, achieving near-zero energy loss, namely ultrahigh efficiency (η), in energy storage capacitors with large recoverable energy storage density (Wrec) plays an important role in applications, which is one of the major challenges in dielectric energy storage field. Here, guided by phase-field simulation, inhomogeneous polarization configuration with multiple symmetries and polarization magnitudes is controlled through aliovalent strongly polar double ion design to establish a strongly disordered state. A record-high η of ≈97.4% is realized in lead-free relaxors with a large Wrec of ≈8.6 J cm-3, which also give a giant Wrec of ≈11.6 J cm-3 with an ultrahigh η of ≈96.1% through high-energy ball milling, showing a breakthrough progress in ceramic capacitors with a maximum figure of merit of 330. This work demonstrates that controlling inhomogeneous polarization configuration is an effective avenue to develop new high-performance near-zero energy loss energy storage capacitors.

Reaction of Partially Methylated Polygalacturonic Acid with Iron(III) Chloride and Characterization of a New Mixed Chloride-Polygalacturonate Complex.

We have described a new route for the preparation of partially methylated polygalacturonic acid containing hydrolyzed (acidic) and unhydrolyzed (methyl esterified) carboxylate groups in a ratio of 1:1 (PGA, compound 1), and one of its basic FeIII-salts (compound 2) with a ~1:2 FeIII:GA stoichiometry (GA means galacturonic acid and methylated galacturonic acid units). The partially hydrolyzed pectin was transformed into compound 1 with the use of double ion exchange with a strongly acidic macroreticular sulfonated styrene-divinylbenzene copolymer as a hydrogen ion source. The reaction of compound 1 with FeCl3 resulted in compound 2. Compound 2 has a polymeric nature and contains binuclear FeIII(µ-O)(µ-OH)FeIII core units with two kinds of distorted octahedral iron geometries. The salt-forming acidic and methylated GA units of compound 1 are coordinated to FeIII centers in asymmetric bidentate-chelating and -bridging (via C=O group and glycosidic oxygen) modes, respectively. Two kinds of outer-sphere chloride anions were also detected by XPS in various chemical environments fixed by different sets of hydrogen bonds. We also observed a partial reduction of FeIII into FeII due to the ring-opening of the chain-end GA units of compound 1. This reaction provides a new route to determine the number of chain-ends in compound 2, and with the use of the number of GA units calculated from charge neutrality, the average length of these chains and the average molecular weight were also determined. The average molecular weight of the partially methylated polygalacturonic acid used in the industrial-scale production of commercial anti-anemic iron-polygalacturonate agents was ~50,000 g/mol. Compound 2 was also characterized by IR, Mössbauer, and X-ray photoelectron spectroscopy, and magnetic susceptibility measurements. These results on the structure and average molecular weight of basic iron(III) polygalacturonate provide a tool to design Fe-PGA complexes with tuned iron-releasing properties.

Surface heterojunction based on n-type low-dimensional perovskite film for highly efficient perovskite tandem solar cells.

Enhancing the quality of junctions is crucial for optimizing carrier extraction and suppressing recombination in semiconductor devices. In recent years, metal halide perovskite has emerged as the most promising next-generation material for optoelectronic devices. However, the construction of high-quality perovskite junctions, as well as characterization and understanding of their carrier polarity and density, remains a challenge. In this study, using combined electrical and spectroscopic characterization techniques, we investigate the doping characteristics of perovskite films by remote molecules, which is corroborated by our theoretical simulations indicating Schottky defects consisting of double ions as effective charge dopants. Through a post-treatment process involving a combination of biammonium and monoammonium molecules, we create a surface layer of n-type low-dimensional perovskite. This surface layer forms a heterojunction with the underlying 3D perovskite film, resulting in a favorable doping profile that enhances carrier extraction. The fabricated device exhibits an outstanding open-circuit voltage (VOC) up to 1.34V and achieves a certified efficiency of 19.31% for single-junction wide-bandgap (1.77eV) perovskite solar cells, together with significantly enhanced operational stability, thanks to the improved separation of carriers. Furthermore, we demonstrate the potential of this wide-bandgap device by achieving a certified efficiency of 27.04% and a VOC of 2.12V in a perovskite/perovskite tandem solar cell configuration.

A signal-on photoelectrochemical sensor based on the target-triggered double-ion exchange reaction for Hg2+ under visible light

A photoelectrochemical (PEC) sensor driven by visible light has been developed to detect Hg2+ with a signal output "turn-on" mode on basic of the double ZIF-Cds@Zns@HgS type-II heterojunction formed by a target-triggered double-ion exchange reaction. The type-II heterojunction photocatalysts ZIF-CdS@ZnS were prepared through growing ZnS nanoparticles onto ZIF-CdS hollow nanocages which were innovatively synthesized using ZIF-67 as a template by MOF-engaged directional deposition strategy. An obvious photocurrent amplification effect induced by mercury ions is evident in ZIF-CdS@ZnS modified ITO electrodes, compared to ZIF-CdS or pure ZnS modified electrodes. The ZIF-CdS@ZnS heterojunction would successfully utilize visible light to promote the photoelectric response process due to the synergistic effect of the narrow band gap component and cavity structure. More importantly, the photocurrent can be greatly amplified by the target-triggered double-ion exchange reaction, which results in the generation of double type-II heterostructures HgS@ZnS@CdS, where an electrical field resulting from the unification of the fermi level facilitates the separation of photogenerated charges and increases the output photocurrent. Besides, the target-triggered double ion exchange strategy can provide guidance for the design of signal-on PEC sensors to detect other heavy metal ions sensitively.

A critical review and meta-analysis of xenon-on-carbon sputter yield data

A systematic review and meta-analysis of sputter yield data for xenon ions normally incident on graphite at energies below 2000 eV was undertaken to identify systematic errors, determine the best model parameter values to represent yield as a function of energy, quantify uncertainty, and determine if the data support differences in yields for different types of graphite. A critical examination of the 11 published data sets for high density graphite, pyrolytic graphite, and amorphous carbon showed that, in general, they were carefully controlled to minimize errors. The most significant quantifiable systematic errors were those caused by the neglect of doubly charged ions, chemical erosion, and the impact of secondary electron emission on ion flux measurements. The effects of gas uptake and outgassing on mass loss measurements and unrepresentative surface textures may have biased other experiments, but these effects could not be quantified. The semi-empirical Eckstein model for yield as a function of energy was fit to data for the three graphite types using a hierarchical Bayesian statistical model, producing recommended fit parameters and probability distributions representing uncertainty in yields. The results showed that differences in yield for high density graphite and pyrolytic graphite were not statistically significant. Apparent differences in yield for amorphous carbon disappeared when the single data set available for energies below 150 eV was corrected for reasonable values of double ion content. Recommended procedures to avoid systematic errors and additional experiments and modeling to fill in gaps in our understanding are included.

An insight into REEs recovery from spent fluorescent lamps: Evaluation of the affinity of an NH4-13X zeolite towards Ce, La, Eu and Y

The constantly increasing demand of Rare Earth Elements (REEs) made them to be part of the so-called “critical elements” indispensable for the energy transition. The monopoly of only a few countries, the so-called balance problem between demand and natural abundance, and the need to limit the environmental costs of their mining, stress the necessity of a recycling policy of these elements. Different methods have been tested for REEs recovery. Despite the well-known ion-exchange properties of zeolites, just few preliminary works investigated their application for REEs separation and recycle. In this work we present a double ion exchange experiment on a NH4-13X zeolite, aimed at the recovery of different REEs from solutions mimicking the composition of liquors obtained from the leaching of spent fluorescent lamps.The results showed that the zeolite was able to exchange all the REEs tested, but the exchange capacity was different: despite Y being the more concentrated REE in the solutions, the cation exchange was lower than less concentrated ones (16 atoms p.u.c. vs 21 atoms for Ce and La solutions), suggesting a possible selectivity. In order to recover REEs from the zeolite, a second exchange with an ammonium solution was performed. The analyses of the zeolites show that almost all of Ce and Eu remain in the zeolite, while nearly half of La and Y are released. This, once again, suggests a possible selective release of REEs and open the possibility for a recovery process in which Rare Earths can be effectively separated.

Statistical analysis of overlapping double ion energy dispersion events in the northern cusp

This article presents a statistical analysis of overlapping double ion-energy dispersion events in the northern cusp (“double dispersion”). Double dispersion in either cusp is a phenomenon associated with multiple reconnections occurring on the dayside magnetosphere as a result of its constant interaction with the variable solar wind. Using observations from a low Earth orbiting (LEO) Defense Meteorological Satellite Program (DMSP) satellite, we analyze 138 dayside events selected by the automatic algorithm extended from our previous work. We conducted a correlation study between the number of detected double dispersion events and 1) the month of the year to analyze the seasonal response of the cusp, and 2) solar wind interplanetary magnetic field (IMF) components and clock/cone angles to investigate its relationship with magnetic reconnection. We found that dispersion events occur more frequently during the northern summer months (i.e., when the dipole is tilted Sunward) and when the By component of IMF is positive. In addition, we provide a machine-readable list of the events and the code used to automatically detect the events.

Hidroxiapatita sustituida con estroncio: plataforma para regeneración ósea con actividad antimicrobiana

Hydroxyapatite (HA) is a calcium phosphate with great analogy to biological apatite. Because of that it has demonstrated excellent results in clinical applications for bone tissue replacement. However, there are certain pathologies such as osteopenia or osteoporosis where the natural bone formation capacity is diminished and which may require an extra stimulus to accelerate and guarantee the osseointegration processes. In these cases, doping hydroxyapatite with strontium ions (Sr-HA) has given excellent results. This ion participates in bone metabolism in various ways and, while stimulating osteosynthesis, it inhibits osteoclast to a certain extent, which as a whole promotes the formation of new bone more quickly. Thus, the development of Sr-HA implants has evolved to not only consider substitutes for bone tissue with greater speed of osseointegration, but also to become platforms for the release of other active ingredients that can also counteract different medical conditions. This work delves into the complexity of septic processes associated with prostheses, which justifies the diversity of approaches to this clinical problem from biomedical engineering. In addition, review different formulations based on Sr-HA reported to eradicate septic processes. In particular, it explores new devices carrying antibiotics (Antb/Sr-HA) and new platforms that have been formed from the double ion doping of the HA where one of those ions is strontium and the other is some metallic element with demonstrated antibacterial activity (M/Sr-HA).

Hybrid polyionic complexes as nanoreactors for the synthesis of iron oxide nanoparticles: From size control to modulation of magnetic and catalytic properties

Hybrid polyion complexes (HPICs) obtained from the complexation in aqueous solution of a double hydrophilic block copolymers and metal ions can act as efficient precursors for the controlled synthesis of hybrid nanoparticles. Hence, HPICs based on a mixture of ferrous and ferric ions with poly(ethylene oxide)-block-poly(acrylic acid) were used to initiate, after the addition at 70 °C of a solution of NH4OH, the formation of iron oxide nanoparticles. The careful choice of the molar ratio between polymer and metal ions within HPICs enables to tune the morphology and size of the obtained iron oxide nanoparticles while maintaining the same surface composition. This control of size and composition was further used to highlight the relationship between the size of these particles and their catalytic and magnetic properties.

The synergistic effects of strontium/magnesium-doped calcium silicate cement accelerates early angiogenesis and bone regeneration through double bioactive ion stimulation

Periodontitis-induced alveolar bone defects necessitate the use of bone grafts for optimal therapeutic outcomes. Therefore, synthetic bone grafts exhibiting consistent properties, sufficient amounts, and multiple application forms have been extensively studied. Our previously designed Ca–Si–Mg cement has demonstrated benefits regarding cell proliferation, osteogenesis, and angiogenesis. Similarly, Sr exhibits osteogenic, anti-osteoclastogenic, and angiogenic properties by influencing several intracellular signaling pathways. In this study, we modified the previously established Ca–Si–Mg cement by incorporating Sr, which resulted in the formation of Mg–Sr-calcium silicate (CS) cement. Furthermore, we evaluated its biocompatibility and efficacy in promoting osteogenesis and angiogenesis. The results revealed that the setting time of the cement was extended with the individual incorporation of either Mg or Sr; notably, the setting time of M5S5 (integrating both Sr and Mg in equal proportions) was 2.7 min shorter than that of M5S0 (integrating only Mg). In addition, the presence of Sr enhanced the mechanical strength to an ultimate strength of 1.89 MPa and reduced the biodegradation rate of the Mg-doped CS cement from a weight loss of 13.9 %–11.5 %. Sr and Mg also demonstrated a synergistic effect on cell proliferation, with no observed cytotoxicity in human periodontal ligament cells (hPDLs). Osteogenic markers such as alkaline phosphate, bone sialoprotein, and osteocalcin were significantly expressed in hPDLs under the combined influence of Mg and Sr on osteogenic activity. Similarly, the angiogenesis-related proteins, vascular endothelial growth factor and angiopoietin-1 exhibited considerable enhancement, indicating the angiogenic capability of M5S5. In summary, our in vitro experiments confirmed that M5S5 is a potential candidate for osteogenic substitutes and alveolar bone regeneration, suggesting its potential applicability in clinical practice.