High-resolution Electron Microscopy Images Research Articles

Tailoring Structural, Microstructural, Dielectric and Gas Sensing Properties of SnO2 Nanoparticles: Size Matters

This manuscript reports on the characteristics of SnO2 nanoparticles (NPs) prepared using the conventional sol-gel technique and showcases the effect of calcination temperature on crystal structure, size, and gas-sensing properties. Rietveld refinement of diffraction profiles of SnO2 NPs calcined at 400 °C [SnO2@400] and 600 °C [SnO2@600] showed that both the samples possess tetragonal phase having space group P 4 / 2 mnm . FESEM microimages of SnO2@400 and SnO2@600 were subjected to morphological analysis using an image processing method. The results showed that the grains exhibited swelling as the calcination temperature increased as per the Ostwald ripening process. High-resolution transmission electron microscopic (HRTEM) image depicted (110) lattice plane orientation with d = 0.34 nm consistent with XRD studies. Thus, the dielectric constant ε ′ was increased from 38 to 56 as the temperature rose to 600 °C from 400 °C. Simultaneously, electrical resistance increased from 0.77 × 106 Ω to 1.27 × 106 Ω with rise in the calcination temperature of SnO2 NPs from 400 °C to 600 °C. The investigation on sensing acetone gas revealed that the SnO2@600 sample possessed the maximum sensing response along with a shorter recovery time compared with SnO2@400.

High-resolution electron microscopy imaging of MOFs at optimized electron dose

Electron dose thresholds were analyzed for pristine and metalated PCN-222 MOFs. RiCOM images from low-dose 4D-STEM experiment data sets, reveal structural details, allowing investigation of local features while minimizing beam-induced damage.

Clerodendrum japonicum (Thunb.) Sweet leaf extract supported nanosilver particles: Characterization, antioxidant and antibacterial activity

Silver nanoparticles have been synthesized in numerous ways, due to their diverse applications, including green procedures that used an extract of plants for the reduction of metal ions. This study delineates the green synthesis and characterization of silver nanoparticles (AgNPs) from the leaf extract of Clerodendrum japonicum (Thunb.) Sweet (CJ) and assesses the antioxidant as well as antibacterial characteristics. The biosynthesis of AgNPs was accomplished by reacting the aqueous leaf extract of the plant with a solution of silver nitrate (AgNO3). The creation of AgNPs was indicated by the visual colour change of the reaction concoction from golden to deep brown and the absorption peak at 442 nanometer (nm) in the ultraviolet-visible spectroscopy. The Field Emission Scanning Electron Microscope (FESEM) and the High-Resolution Transmission Electron Microscope (HRTEM) images have revealed the generated AgNPs as spherical and oblate in shape which is 20-40 nm in size, whereas X-Ray power Diffraction evaluation revealed the crystalline feature. The existence of functional groups of synthesized AgNPs was detected by the Fourier Transform Infra-Red (FTIR) spectrum. The synthesized AgNPs showed free radical scavenging activity using 2, 2-Diphenyl-1-picryl hydrazyl assay with IC50 value, 7.02±1 μg/mL. The antibacterial assay showed an effective activity towards E. Coli and S. aureus by developing a well-defined zone of inhibition. The results of this study accentuate the biomedical potential of the above-mentioned plant, though further research is needed to implement it in clinical practice.

On the long-term storage of tissue for fluorescence and electron microscopy: lessons learned from rat liver samples

Occasionally, tissue samples cannot be processed completely and are stored under varying conditions for extended periods. This is particularly beneficial in interinstitutional studies where a given research setting may lack the expertise or infrastructure for sample processing, imaging and data analysis. Currently, there is limited literature available on the controlled storage of biological tissues in primary fixatives for fluorescence and electron microscopy. In this contribution, we mimicked various tissue storage scenarios by taking different fixation conditions, storage temperatures and storage durations into account. Rat liver tissue was used for its well-known diversity of cellular ultrastructure and microscopy analysis. Fluorescent labelling of actin, DNA and lipids were employed in conjunction with high-resolution electron microscopy imaging. Herein, we tested three different fixative solutions (1.5% glutaraldehyde, 0.4% glutaraldehyde and 4% formaldehyde and 4% formaldehyde) and stored samples for 1–28 days at room temperature and refrigerator temperature. We found that liver tissue can be stored for up to 2 weeks in a 0.4% glutaraldehyde + 4% formaldehyde fixative solution, while still enabling reliable fluorescent labelling and ultrastructural studies. Ultrastructural integrity was eminent up to 1 month using either glutaraldehyde or formaldehyde fixation protocols. When liver tissue is fixed with a mixture of 0.4% glutaraldehyde and 4% formaldehyde and stored at 4 °C, it retains its capacity for electron microscopy analysis for several years, but loses its capacity for reliable fluorescent labelling studies. In conclusion, we demonstrated that liver tissue can be stored for extended periods enabling profound structure–function analysis across length scales.

Structural characterization of cage clusters assembled borophene and implication for cathode electrocatalysts in Li–O2 batteries

The successful fabrication of quasi-freestanding bilayer borophene in experiments, combined with its superior metallic character, has propelled it to a rising star among two-dimensional materials, making it highly promising for applications in micro-electronic devices. Using first-principles calculations, we comprehensively explore and characterize cage cluster assembled borophenes through various methods for experimental references. The simulated scanning tunneling microscope (STM) images under diverse bias voltages exhibit distinct morphologies and closely associated with the partial densities of states (PDOS) of the surface boron atoms. High-resolution and large-scale simulated transmission electron microscope (TEM) images are investigated to detect the internal crystal structures, facilitating better identification of non-monolayer borophenes. The partial densities of states, electronic localization functions and Mulliken bond populations have been calculated to analyze the differences of morphology in STM and TEM images. Furthermore, simulated X-ray diffraction (XRD), Raman, and infrared (IR) spectra are characterized to further assist in distinguishing the phases of borophene. In light of ultrahigh stability and excellent metallic character, cluster assembled borophene of P3¯m1 symmetry act as cathode materials of Li-O2 battery with lower overpotential in oxygen evolution reaction (OER) than oxygen reduction reaction (ORR) processes. The overpotential is closely related to the adsorption strength of LiO2 and Li2O2 intermediates on surface of boron sheets. These theoretical results offer crucial guidance for the experimental identification of borophenes and suggest that the new type of cluster assembled systems might be suitable for the cathode materials of future Li-O2 batteries.

Engineering Delocalized Polarizations in Metal Oxide Electrodes with Conducting Polymers for Efficient and Durable Water-Splitting.

Oxygen evolution reaction is a pivotal anodic reaction for electrolysis, however, it remains the obstacle from its sluggish reaction kinetics originating from multiple electron transfer pathways at electrochemical interfaces. Especially, it remains a challenge to achieve stable operation at elevated current densities as electrodes suffer oxidative environment in corrosive conditions. Herein, we report that the conducting polymer polypyrrole electrodeposited Pr0.7Sr0.3CoO3 perovskite oxides for durable oxygen evolution electrodes. We found that the conducting polymer electrodeposited oxides exhibited a highly durable electrochemical oxygen evolution performance maintaining >99 % of initial activities during the accelerated durability test. Meanwhile, bare metal oxides presented significant performance drops (<6 % of initial activities) over the consecutive 20,000 accelerated durability test. High-resolution transmission electron microscope images identified the maintenance of high crystallinity of the heterostructure, suggesting that the electrodeposited pPy clusters can effectively delocalize highly polarized electrodes preventing material corrosion. The overall water electrolysis experiments further demonstrated that the heterostructure showed excellent stability at the high current density of 100 mA cm-2 over 700 hours. This marks the first report of the delocalized polarization benefiting from conducting polymers for durable oxygen evolution for perovskite oxides, suggesting great potential for scalable water electrolysis.

CsPbBr3-PbSe Perovskite-Chalcogenide Epitaxial Nanocrystal Heterostructures and Their Charge Carrier Dynamics.

Lead halide perovskite and chalcogenide heterostructures which share the ionic and covalent interface bonding may be the possible materials in bringing phase stability to these emerging perovskite nanocrystals. However, in spite of significant successes in the development of halide perovskite nanocrystals, their epitaxial heterostructures with appropriate chalcogenide nanomaterials have largely remained unexplored. Keeping the importance of these materials in mind, herein, epitaxial nanocrystal heterostructures of CsPbBr3-PbSe are reported. The shape remained rhombic dodecahedral-tetrahedral, and the phase retained orthorhombic-cubic for CsPbBr3 and PbSe nanocrystals, respectively. These are synthesized following the standard classical approach of heteronucleations of chalcogenide PbSe with CsPbBr3 perovskite nanostructures and characterized with high-resolution electron microscopic imaging. With an ultrafast study, the hot charge transfer from CsPbBr3 to PbSe is also established. As these are first of its kind nanostructures which are obtained with heteronucleation and growth of chalcogenides on halide perovskites, this finding is expected to open the roadmap for designing other heterostructures which are important for catalysis and photovoltaic applications.

From two segments and beyond: Investigating the onset of regeneration in Syllis malaquini.

Annelids feature a diverse range of regenerative abilities, but complete whole-body regeneration is less common, particularly in the context of the head and anterior body regeneration. This study provides a detailed morphological description of Syllis malaquini regenerative abilities. By replicating previous experiments and performing diverse surgical procedures, we explored the capacity of this species for whole-body regeneration. We detailed the precise timing of regeneration of particular structures such as the eyes, proventricle, pharyngeal tooth, nuchal organs, and body pigmentation after amputation. Our high-resolution scanning electron microscopy and confocal laser-scanning microscopy images provide details of the blastema region, revealing that while anal opening remains in connection to the exterior environment, oral opening is formed "de novo" during blastema differentiation. Additionally, we performed amputations to isolate fragments consisting of one, two, and three segments from the intestinal trunk region. We found that S. malaquini requires at least two to three segments to successfully regenerate the whole body. In addition, we verified a variable capacity to regenerate depending upon the gut region, with structures of the foregut greatly impairing some steps of the regenerative process. Our work notably addresses the gap in knowledge concerning gut formation and its impact on regenerative capabilities. Ongoing research is crucial to unravel the role of gut tissue specificity and plasticity during regeneration in annelids, and particularly in syllids.

Size-Resolved Shape Evolution in Inorganic Nanocrystals Captured via High-Throughput Deep Learning-Driven Statistical Characterization.

Precise size and shape control in nanocrystal synthesis is essential for utilizing nanocrystals in various industrial applications, such as catalysis, sensing, and energy conversion. However, traditional ensemble measurements often overlook the subtle size and shape distributions of individual nanocrystals, hindering the establishment of robust structure-property relationships. In this study, we uncover intricate shape evolutions and growth mechanisms in Co3O4 nanocrystal synthesis at a subnanometer scale, enabled by deep-learning-assisted statistical characterization. By first controlling synthetic parameters such as cobalt precursor concentration and water amount then using high resolution electron microscopy imaging to identify the geometric features of individual nanocrystals, this study provides insights into the interplay between synthesis conditions and the size-dependent shape evolution in colloidal nanocrystals. Utilizing population-wide imaging data encompassing over 441,067 nanocrystals, we analyze their characteristics and elucidate previously unobserved size-resolved shape evolution. This high-throughput statistical analysis is essential for representing the entire population accurately and enables the study of the size dependency of growth regimes in shaping nanocrystals. Our findings provide experimental quantification of the growth regime transition based on the size of the crystals, specifically (i) for faceting and (ii) from thermodynamic to kinetic, as evidenced by transitions from convex to concave polyhedral crystals. Additionally, we introduce the concept of an "onset radius," which describes the critical size thresholds at which these transitions occur. This discovery has implications beyond achieving nanocrystals with desired morphology; it enables finely tuned correlation between geometry and material properties, advancing the field of colloidal nanocrystal synthesis and its applications.

A machine learning–based framework for mapping hydrogen at the atomic scale

Hydrogen, the lightest and most abundant element in the universe, plays essential roles in a variety of clean energy technologies and industrial processes. For over a century, it has been known that hydrogen can significantly degrade the mechanical properties of materials, leading to issues like hydrogen embrittlement. A major challenge that has significantly limited scientific advances in this field is that light atoms like hydrogen are difficult to image, even with state-of-the-art microscopic techniques. To address this challenge, here, we introduce Atom-H, a versatile and generalizable machine learning-based framework for imaging hydrogen atoms at the atomic scale. Using a high-resolution electron microscope image as input, Atom-H accurately captures the distribution of hydrogen atoms and local stresses at lattice defects, including dislocations, grain boundaries, cracks, and phase boundaries. This provides atomic-scale insights into hydrogen-governed mechanical behaviors in metallic materials, including pure metals like Ni, Fe, Ti and alloys like FeCr. The proposed framework has an immediate impact on current research into hydrogen embrittlement and is expected to have far-reaching implications for mapping "invisible" atoms in other scientific disciplines.

Controllable growth of large 1T-NbTe2 nanosheets on mica by chemical vapor deposition and its magnetic properties

Two-dimensional (2D) magnetic materials have recently attracted broad attention for their potential technological applications. Here, we report controllable growth of NbTe2 nanosheets on mica substrate by atmospheric chemical vapor deposition. Different from the SiO2/Si substrates, dangling bonds on the surface of the mica are absent, which induces low nucleation density and higher lateral growth rate. As a result, the lateral size of NbTe2 nanosheets on mica substrates can be significantly larger than those on SiO2/Si substrates. Large single crystal NbTe2 nanosheets with a lateral size of up to 151 µm were fabricated on a mica. High-resolution transmission electron microscope image, XRD patterns and Raman spectra reveal the NbTe2 nanosheets adopt the single crystal with 1T phase. Furthermore, the NbTe2 nanosheets on mica demonstrate ferromagnetic properties with a Curie temperature of up to 162 K. Our work paves the way for the atmospheric chemical vapor deposition growth and applications of many more 2D magnets.

Emerging 2D nanoscale metal oxide sensor: semiconducting CeO2nano-sheets for enhanced formaldehyde vapor sensing.

Herein, we fabricated nanoscale 2D CeO2sheet structure to develop a stable resistive gas sensor for detection of low concentration (ppm) level formaldehyde vapors. The fabricated CeO2nanosheets (NSs) showed an optical band gap of 3.53 eV and cubic fluorite crystal structure with enriched defect states. The formation of 2D NSs with well crystalline phases is clearly observed from high-resolution transmission electron microscope (HRTEM) images. The NSs have been shown tremendous blue-green emission related to large oxygen defects. A VOC sensing device based on fabricated two-dimensional NSs has been developed for the sensing of different VOCs. The device showed better sensing for formaldehyde compared with other VOCs (2-propanol, methanol, ethanol, and toluene). The response was found to be 4.35, with the response and recovery time of 71 s and 310 s, respectively. The device showed an increment of the recovery time (71 s to 100 s) with the decrement of the formaldehyde ppm (100 ppm to 20 ppm). Theoretical fittings provided the detection limit of formaldehyde ≈8.86 ± 0.45 ppm with sensitivity of 0.56 ± 0.05 ppm-1. The sensor device showed good reproducibility with excellent stability over the study period of 135 d, with a deviation of 1.8% for 100 ppm formaldehyde. The average size of the NSs (≈24 nm) calculated from HRTEM observation showed lower value than the calculated Debye length (≈44 nm) of the charge accumulation during VOCs sensing. Different defect states, interstitial and surface states in the CeO2NSs as observed from the Raman spectrum and emission spectrum are responsible for the formaldehyde sensing. This work offers an insight into 2D semiconductor-based oxide material for highly sensitive and stable formaldehyde sensors.

Achieving high sheet resistance and near-zero temperature coefficient of resistance in NiCr film resistors by Al interlayers

Thin film resistive materials with low temperature coefficients of resistance (TCR) and high sheet resistances are essential for various electronic applications, such as embedded resistors. In this study, Al inserting layers and NiCr resistive layers were sequentially deposited on alumina ceramic substrates via DC magnetron sputtering to fabricate Al/NiCr bilayer resistive materials. The electrical properties of the bilayer films were adjusted by varying the thicknesses of the Al inserting layers and annealing conditions. When the thickness of the Al inserting layer varied from 5 to 7.5 nm, and post-annealing treatments ranging from 200℃ to 400℃ were applied, evident Al-NiCr interdiffusion occurred, forming intermediate layers at the interfaces and oxides on the film surfaces. A mixture of partial crystalline phases and amorphous phases was also observed in the cross-sectional high-resolution transmission electron microscope (HRTEM) images. The formation of intermediate layers and surface oxides and the balance between partial crystalline phases and amorphous phases collectively enhanced the electrical performance of bilayer film resistors, achieving thin film resistors with a remarkably low TCR of −6.61 ppm/K and a sheet resistance of up to 265.95 Ω/sq. By rational design of Al layers, NiCr layers and thermal treatment, thin film resistors with near zero TCRs and extremely wide sheet resistance range of 93.34–1439.01 Ω/sq can be obtained.

Polymorphic Localized Heterostructure Design for High-Performance Amorphous/Nanocrystalline Composite Film.

Analogous to linear dielectric, amorphous perovskite dielectrics characterized of high breakdown strength and low remanent polarization possess in-depth application in the sea, land, and air fields. Amorphous engineering is a common approach to balance the inverse relationship between polarization and breakdown strength in dielectric ceramic capacitor, however, the low polarization is the major barrier limiting the improvement of energy storage density. To address this concern, the polymorphic localized heterostructure confirmed by high-resolution transmission electron microscope (HR-TEM) and HADDF images is constructed in BaTiO3-Bi(Ni0.5Zr0.5)O3 amorphous/nanocrystalline composite film with SiO2 addition (BT-BNZ-xS, x = 3, 5, 7, 10 mol%). The stability of nanocrystalline region achieved by Si-rich transition region and the enhancive ultra-short-range ordering in the amorphous region synergistically result in large breakdown strength and nonhysteretic polarized response. This polymorphic localized heterostructure optimizes the thermal stability in a wide temperature range and contributes ultrahigh energy storage density of 149.9 J cm-3 with markedly enhanced efficiency of 79.0%. This study provides a universal strategy to design the polarization behavior in other amorphous perovskite-based dielectrics.

Chirality Determination of Nanocrystals by Electron Crystallography.

Chirality is a common phenomenon in nature and plays an important role in the properties of matter. The rational synthesis of chiral compounds and exploration of their applications in various fields require an unambiguous determination of their handedness. However, in many cases, determinations of the chiral crystal structure and chiral morphology have been a challenging task due to the lack of proper characterization methods, especially for nanosized crystals. Therefore, it is crucial to develop novel and efficient characterization methods. Owing to the strong interactions between matter and electrons, electron crystallography has become a powerful tool for structural analysis of nanomaterials. In recent years, methods based on electron crystallography, such as high-resolution electron microscopy imaging and electron diffraction, have been developed to unravel the chirality of nanomaterials. This brings new opportunities to the design, synthesis, and applications of versatile chiral nanomaterials. In this perspective, we summarize the recent methodology developments and ongoing research of electron crystallography for chiral structure and morphology determination of nanocrystals, including inorganic and organic materials, as well as highlight the potential and further improvement of these methods in the future.

A Comparative Study on Dip Coating and Corrosion Behavior of Ti-13Zr-13Nb and Commercially Pure Titanium Alloys Coated with YSZ by Taguchi Design

This work evaluates experimentally the corrosion and tip testing of Ti-13Zr-13Nb joint implant alloys and commercially pure titanium (cp-Ti) covered with YSZ nanoceramic. Through the use of the Taguchi design of experiments (DOE) approach, the dip coating process produced a thin sticky covering. The effects of temperature, YSZ concentration, duration, and the level of Ti alloy substrate grinding during dip coating were investigated using a L9-type orthogonal Taguchi array to determine the deposition yield. The thickness and adhesion tests that were utilized to optimize the dip coating conditions served as the input data, and the Ti alloys were coated using the ideal dip coating technique parameters as previously mentioned. For commercial Ti, the ideal values for YSZ coating thickness and adhesion were 60°C, 10 seconds, 10% concentration, and 250 degrees of grinding; correspondingly, for Ti-13Zr-13Nb, the ideal values were 60°C, 10 seconds, 15% concentration, and 400 degrees of grinding. For both Cp-Ti and Ti-13Zr-13Nb, the obtained thickness and removal area (adhesion) were 58.5µm and 11.45%, respectively, and 69.5µm and 9.33%, respectively. High-resolution scanning electron microscopy (FE-SEM) images were used to study the coated alloys; optical microscopy and AFM were used to identify the microstructure and thickness measurements of the coated surfaces; EDAX was used to analyze the coating composition; and XRD was used to analyze the formed phases. The optimized coated Ti alloys' corrosion resistance was investigated in simulated body fluid (SBF) using electrochemical methods such as cyclic polarization and Tafel polarization, and the adhesion strength of the coatings was measured using a tip tester. The following corrosion-resistant values were used to compare Ti-13Zr-13Nb and coated Cp-Ti: In Ringer's solution at 37°C, both coating alloys—Cp-Ti and Ti-13Zr-13Nb—improved corrosion resistance; however, the coated Ti-13Zr-13Nb alloy demonstrated greater corrosion resistance than the coated Cp-Ti alloy (5.417×10-3 and 1.042×10-2, respectively).

Tuning the End Alkyl Chain of the Ether Solvent to Stabilize the Electrode/Electrolyte Interfaces in the NCM-Li Battery.

Lithium metal batteries (LMBs) combined with a high-voltage nickel-rich cathode show great potential in meeting the growing need for high energy density. The lack of advanced electrolytes has been a major obstacle in the commercialization of high-voltage lithium metal batteries (LMBs), as these electrolytes need to effectively support both a stable lithium metal anode (LMA) and a high-voltage cathode (>4 V vs Li+/Li). In this work, by extending the two terminal methyl groups in DIGDME and TEGDME to n-butyl groups, we design a new weakly solvating electrolyte (2 M LIFSI+TEGDBE) that enables the stable cycling of NMC83 (LiNi0.83Co0.12Mn0.05O2) cathodes. The NMC83 cell exhibits a high and stable Coulombic efficiency (CE) of over 99%, as well as capacity retention of approximately 99.8% after 100 cycles at 0.3 C. X-ray photoelectron spectroscopy analysis (XPS) and high-resolution transmission electron microscope (HRTEM) images revealed that the anion species decomposed first, resulting in the formation of a cathode-electrolyte interface (CEI) film predominantly consisting of decomposition products from the anions on the positive electrode surface. This work links the functional group of solvents with the solvation structure and electrochemical performance of ether-based electrolytes, providing a distinctive sight to design advanced electrolytes for high-energy-density LMBs.

Cryo-EM combined with image deconvolution to determine ZIF-8 crystal structure

Abstract Metal–organic frameworks (MOFs) are crystalline porous materials with tunable properties, exhibiting great potential in gas adsorption, separation and catalysis.[1,2] It is challenging to visualize MOFs with transmission electron microscopy (TEM) due to their inherent instability under electron beam irradiation. Here, we employ cryo-electron microscopy (cryo-EM) to capture images of MOF ZIF-8, revealing inverted-space structural information at a resolution of up to about 1.7 Å and enhancing its critical electron dose to around 20 e −/Å2. In addition, it is confirmed by electron-beam irradiation experiments that the high voltage could effectively mitigate the radiolysis, and the structure of ZIF-8 is more stable along the [100] direction under electron beam irradiation. Meanwhile, since the high-resolution electron microscope images are modulated by contrast transfer function (CTF) and it is difficult to determine the positions corresponding to the atomic columns directly from the images. We employ image deconvolution to eliminate the impact of CTF and obtain the structural images of ZIF-8. As a result, the heavy atom Zn and the organic imidazole ring within the organic framework can be distinguished from structural images.

Evaluating nickel removal efficacy of Filtralite under laboratory conditions: Implications for sustainable urban drainage systems

Our study deals with the critical issue of heavy metal pollution in urban runoff; we focused particularly on the threat posed by heavy metals such as nickel to living organisms and water resources owing to their toxicity at low concentrations and non-biodegradability. In this study, we evaluated the efficacy of Filtralite, a filtration medium with excellent hydraulic properties, in removing nickel from water through laboratory experiments and advanced simulation tools. We analysed the geochemical processes involved in nickel removal, including precipitation and adsorption. Importantly, we implemented an innovative approach for numerical modelling using HP1, by combining HYDRUS-1D and PHREEQC for modelling solute transport in porous media and geochemical reactions, respectively. The experimental results revealed that the Filtralite-laden column achieved a removal efficiency of 93.5 % for injected nickel. We observed a significant increase in the effluent pH from 7.0 to 11.5 during the interaction with Filtralite, affecting the solubility of the nickel phases. The model showed the highest nickel concentration in the initial column layers because of rapid chemical precipitation and adsorption upon contact with Filtralite. High-resolution scanning electron microscopy images confirmed the presence of amorphous precipitates around the soil particles, aligning with the changes in pH. This study contributes significantly to environmental engineering and urban water management by introducing an innovative numerical model in HP1 to accurately simulate the removal of nickel using Filtralite. These findings validate the efficiency of Filtralite in extracting nickel from aqueous solutions. Thus, Filtralite is a strong candidate for inclusion in sustainable urban drainage systems.

A deconvolution analysis strategy on the thermoreconstitution process of Co/Fe layered double hydroxides: Complementary correlations between physicochemical variations and thermokinetic analyses

A variety of physicochemical analyses were systematically conducted on the complex thermoreconstitution process of Co/Fe layered double hydroxides, and deconvolution analysis strategy was utilized in elucidating the reconstitution process. The thermal analysis of Co/Fe layered double hydroxides indicated that approximately 27.8 % weight loss, three weight loss peaks and two pronounced endothermic phenomena were detected via thermogravimetry, differential thermogravimetry, and differential scanning calorimetry, respectively. In the thermoreconstitution process of Co/Fe layered double hydroxides, scanning electron microscopy images indicated that the layered structure gradually collapsed, fractured into pieces, and partially melted. Meanwhile, significant X-ray diffraction peak broadening phenomena were detected and further confirmed by the d-spacing values in high-resolution transmission electron microscope images, which were mainly caused by the lattice expansion effect and the heterogeneous microstrain effect. Three reactions were deconvolved from the differential thermogravimetry curves, and the thermokinetic models of Reaction 2 indicated that volatile components in the form of H2O and CO2 escaped from the solid-state residuals via a one-dimensional diffusion reaction model. The major products in solid-state residuals were cubic Cobalt(III) oxide and Iron(II, III) oxide. The thermokinetic models played a complementary role in elucidating the physicochemical variations that occurred throughout the thermoreconstitution process of Co/Fe layered double hydroxides.