Degree Of Crystallinity Research Articles

Verification of a method for determining the degree of crystallinity using experimental and computer-generated powder diffraction patterns. Corrigendum

An erroneous equation and some values of related parameters in the paper by Toraya [J. Appl. Cryst. (2023), 56, 1751–1763] are corrected.

Determination of the degree of crystallinity of polyphenylene sulfide composited with crystalline and non-crystalline fillers by applying the direct derivation method. Corrigendum

An erroneous equation and some values of related parameters in the paper by Toraya [J. Appl. Cryst. (2024), 57, 1115–1126] are corrected.

Phytogenic Synthesis of Cuprous and Cupric Oxide Nanoparticles Using Black jack Leaf Extract: Antibacterial Effects and Their Computational Docking Insights

Background: Green synthesized nanoparticles (NPs) have gained increasing popularity in recent times due to their broad spectrum of antimicrobial properties. This study aimed to develop a phytofabrication approach for producing cuprous (Cu2O) and cupric oxide (CuO) NPs using a simple, non-hazardous process and to examine their antimicrobial properties. Methods: The synthesis employed Bidens pilosa plant extract as a natural reducing and stabilizing agent, alongside copper chloride dihydrate as the precursor. The biosynthesized NPs were characterized through various techniques, including X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier-transform infrared (FT-IR) spectroscopy, ultraviolet–visible (UV-Vis) spectroscopy, scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS). Results: XRD analysis confirmed that the synthesized CuO and Cu2O NPs exhibited a high degree of crystallinity, with crystal structures corresponding to monoclinic and face-centered cubic systems. SEM images revealed that the NPs displayed distinct spherical and sponge-like morphologies. EDS analysis further validated the purity of the synthesized CuO NPs. The antimicrobial activity of the CuO and Cu2O NPs was tested against various pathogenic bacterial strains, including Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, and Bacillus cereus, with the minimum inhibitory concentration (MIC) used to gauge their effectiveness. Conclusions: The results showed that the phytosynthesized NPs had promising antibacterial properties, particularly the Cu2O NPs, which, with a larger crystal size of 68.19 nm, demonstrated significant inhibitory effects across all tested bacterial species. These findings suggest the potential of CuO and Cu2O NPs as effective antimicrobial agents produced via green synthesis.

Melt Expansion and Thermal Transitions of Semiconducting Polymers in Thin Films

AbstractThe molecular self‐organization and reorganization and thus volumetric and density changes during structural relaxation and melting of modern organic semi‐conducting materials remains largely unknown, particularly in the device relevant thin film geometry where the initial state may be structurally quenched away from equilibrium. Here, the apparent mass‐thickness of a range of semi‐conducting polymeric or molecular model materials systems is measured through in situ ellipsometry. Surprisingly, the volume changes upon melting correlate inversely, with a few exceptions, to the quality of crystallinity found via x‐ray methods (i.e., directly correlate with the paracrystalline g‐parameter) rather than the melting enthalpy that is possibly a proxy for the degree of crystallinity. This study also observes changes in orientation and/or density due to segmental relaxation during the first heat, thus complementing other characterization methods that measure relaxation or reorganization transitions. Semiconducting materials exhibit very large melt expansion and a richer phase‐behavior compared to commodity polymers, presumably due to their complex chemical structure. The results delineate an important and novel structure‐function relation that, together with simulations constrained by these results, will lead to better rational design of semi‐conducting materials.

RAMAN Analysis of Carbonaceous Material and Deduced Peak Metamorphic Temperatures of Metasediments From Western Himalaya, NW Pakistan

ABSTRACTRaman spectroscopy of carbonaceous materials (RSCM) was applied to 10 carbonaceous material (CM) ‐rich low‐ to medium‐grade metasedimentary rock samples of Western Himalaya, Pakistan to assess their optimum thermal evolution. The RSCM thermometry is based on the degree of graphitisation of CM as a function of peak metamorphic temperature. Petrographic observations of the studied samples revealed two dominant CM morphologies. Type‐I CM, represented by fine‐grained discontinuous dust‐like and scattered to thin sporadic layers, was more prevalent in low‐grade metamorphic samples. Type‐II CM, corresponding to continuous and extended thick fibres and elongated grain constellations, was dominant in medium‐ to high‐grade metamorphic samples. The degree of crystallinity of CM and subsequent metamorphic temperatures were quantified by considering the intensity‐based R1 and the area‐based R2 ratio parameters. Low‐grade samples from the Lesser Himalayan Sequence (LHS), having Type‐I CM, resulted in RSCM peak temperatures between 306°C and 403°C. Medium‐ to high‐grade samples from Higher Himalayan Crystalline (HHC), containing Type‐II CM, yielded peak temperatures in the 482°C–560°C range. The extremely deformed sample from a fault zone in the LHS produced relatively higher temperature of 403°C, thereby suggesting heat associated with shearing due to fault activities resulting in CM recrystallisation and elevated temperature values. The study revealed that the peak metamorphic temperatures increase from south towards north following a progressive path of metamorphism in the region.

Comparison of low-velocity impact damage in laminated composites for two thermoplastic material systems

Aircraft manufacturers are investigating thermoplastic material systems to produce parts more quickly and efficiently. Detailed damage data is needed to evaluate existing damage analysis methods, developed for thermoset materials, to predict damage in thermoplastic materials. Damage maps were created for two thermoplastic material systems subjected to low-velocity impact over a range of impact energies. In this paper, the damage maps were used to investigate and compare the damage response of the different material systems. Impact specimens were manufactured from TC1225 LMPAEK T700G from Toray Industries and APC AS4D/PEKK-FC from Solvay. The effect of the degree of crystallinity on the damage response was also investigated using a third set of specimens manufactured using the Toray material and a quenching process. Using a combination of data obtained from X-ray computed tomography and ultrasonic testing, damage maps were created for every interface and ply for selected specimens showing matrix cracks, delamination outlines, and fractured fibers. The LMPAEK specimens were found to have fewer and smaller delaminations than the PEKK specimens for impacts at the same energy. However, the LMPAEK specimens contained a larger number of fiber breaks. A similar trend was observed when comparing low-crystallinity LMPAEK specimens with the baseline LMPAEK specimens. The LMPAEK specimens often contained lines of fiber fractures in near-surface plies emanating from the contact region that were not present in the PEKK specimens. The different damage responses may indicate that the material selection will be a function of the application and loading.

Crystallization behavior and thermal properties of octa-phenyl-substituted silsesquioxane-modified polylactide (PLA)

AbstractThis study aims to understand the effects of adding octa-phenyl-substituted silsesquioxane (phSQ) on the crystallization process and thermal stability of polylactide (PLA). Nowadays, PLA is the most industrially used compostable polymer, but its uses are limited by its low crystallization and thermal degradation during processing. The possibility of introducing functionalized silsesquioxanes (SQs) to improve thermal stability and increase its crystallinity and ductility in a controlled way is desirable. The nanometric size of the Si-O-Si cage, coupled with the influence of the functional groups attached to its structure, enables it to function as a heterogeneous nucleating agent. In this work, a specially synthesized octa-phenyl-substituted SQ (phSQ) was added to the PLA in 0.5–5 wt%. Crystallization in non-isothermal and isothermal conditions was conducted and monitored using differential scanning calorimetry (DSC); the course of the spherulite formation under identical conditions to DSC was also assessed using optical microscopy in polarized light. The results showed that phSQ increases the degree of crystallinity of PLA by introducing additional sites of heterogeneous nucleation but does not increase the spherulite growth coefficient. Additionally, the analysis of thermal properties indicates that the presence of phSQ could not have a positive impact on thermal stability. The agglomeration of the nanometric particles and changes in the main structural features of the polymeric matrix could be present in the samples, affecting the obtained results. Graphical abstract

PHYSICO-CHEMICAL PROPERTIES OF MALIN-UROTROPIN- COPPER SULFATE SYSTEM

Before seed treatment, the seed must contain several active ingredients. Because the mail significant part of the saved crop depends on the correct seed dressing technology. Seed dressing, or seed treatment with pesticides, is an activity aimed at protecting plants from pests and diseases, using special preparations. In this study, the physicochemical properties of the formalin-urotropine-copper sulfate system were investigated at 25 oC. It is established that the isotherms of the system confirmed that the density, viscosity, pH of the solution medium and the crystallization temperature are characterized by inflection points corresponding to concentrations. Analysis of the “composition - properties” diagram of the system shows that the isotherms of the refractive index, density, viscosity and pH of the medium are characterized by two inflection points corresponding to 30 % formalin and 15 % urotropine that equals molar ratio of 1:1:1. Thus, it can be assumed that the interaction of formalin with copper sulfate in aqueous solutions results in the formation of a complex compound of the composition [30 % CH2O +15 % C6H12N4]-CuSO4·5H2O. Based on the data obtained, a solubility diagram was constructed, identified by X-ray phase, IR spectroscopic and thermogravimetric. Comparison of the value of the degree of crystallinity of the studied samples shows that the degree of crystallinity increases in the samples.

Features of the change in the thermal coefficient of electrical resistance upon heating electrically conductive composites of crystallizable polyolefins with carbon black

Objectives. To investigate electrically conductive polymer composite materials (EPCMs) based on crystallizable polyolefins and electrically conductive carbon black for the production of self-regulating heaters; to study the mechanism of the occurrence of positive and negative temperature coefficients (PTC and NTC) upon heating such composites.Methods. A comprehensive study of the structure and properties of crystallizable EPCMs with electrically conductive technical carbon was carried out. In order to measure the electrical characteristics of the composites, they were compacted into plates to model polymer heaters. Contact electrodes made of an ungreased brass mesh were embedded in their ends. The temperature dependencies of the electrical characteristics of the samples were investigated in a modified thermal chamber of an FWV 633.10 Vicat softening temperature meter. The change in the degree of crystallinity was analyzed by means of differential scanning calorimetry with a NETZSCH DSC 204 F1 Phoenix calorimeter. The dilatometric and rheological characteristics of the samples were studied using an IIRT-AM melt flow index tester.Results. It was determined that the self-regulation ability (an abnormally high positive thermal coefficient of electrical resistance) of selfregulating heaters made of composites of crystallizable polyolefins with electrically conductive technical carbon cannot be explained by the thermal expansion of EPCMs alone. It was shown that in crystallizable polyolefin-based EPCMs, the inversion of the thermal coefficients of electrical resistance (transition from PTC to NTC) is associated with a change in the aggregate state of EPCMs and the beginning of its transition to a viscous-flow state. A mechanism involving a sharp increase in the electrical resistance of self-regulating crystallizable polyolefin-based composite with electrically conductive technical carbon was proposed and substantiated. This mechanism takes into account the additional shear deformation effect produced on the crystalline phase of the EPCM by numerous expanding melt microvolumes formed at the early stages of the melting process with a minimum change in the degree of crystallinity.

Exploring the Acetobacteraceae family isolated from kombucha SCOBYs worldwide and comparing yield and characteristics of biocellulose under various fermentation conditions

Bacterial cellulose (BC) is a cellulosic biopolymer produced by specific acetic acid bacteria during kombucha fermentation. In this study, bacterial cellulose-producing strains were isolated from four different global kombucha SCOBY samples obtained from markets in the Netherlands, America, China, and Iran. The strains were identified using biochemical and molecular techniques. The ability of species to produce BC was evaluated under both static and stirred fermentation conditions. Seven dominant strains from the Acetobacteraceae family and the genus of Komagataeibacter and Gluconacetobacter were identified and submitted to NCBI gene bank archives: K. xylinus CH1, K. sucrofermentans IR2, K. intermedius IR3, K. cocois AM2, K. sucrofermentans NE4, K. cocois NE6, and G. liquefaciens NE7. Among these, K. intermedius IR3, isolated from local Iranian SCOBY, exhibited the highest BC production yield at 5.733 ± 0.170 gL−1 under static fermentation conditions. On the other hand, K. xylinus CH1, from Chinese SCOBY, had the highest yield under stirred conditions, producing 12.689 ± 0.808 gL−1 of BC. The BC production yield of both K. xylinus CH1 and K. intermedius IR3 under stirred conditions was 3 and 1.3 times more than static conditions, respectively. Despite the yield differences, static fermentation demonstrated superior physicochemical characteristics; such as moisture content, water holding capacity, and crystallinity degree, compared to stirred. Therefore, depending on the intended application in industry and specific criteria, both products could serve as functional substitutes in food and medicine sectors.

Comparative Analysis of Structural, Optical, and Electronic Properties of Nickel Oxide and Potassium‐Doped Nickel Oxide Nanocrystals

ABSTRACTMetal oxide semiconductors, known for their exceptional optical transparency, high carrier mobility, and stability, have found extensive use in emerging technologies such as optoelectronics and energy storage devices. Among all metal oxide semiconductors, nickel oxide (NiO) stands out as a highly favorable candidate due to its p‐type conductivity along with its substantial band gap (3.5–4 eV) for the broad range of applications, including gas sensors, high‐rate Lithium‐ion batteries, high‐performance supercapacitors, and photovoltaic devices. In light of these versatile applications, our current study presents a comprehensive comparative analysis of the structural and optoelectronic properties of NiO and potassium (K)‐doped NiO nanocrystals. The nanocrystals were synthesized using the co‐precipitation route and subsequently annealed at 500°C under ambient conditions. The effect of K doping on the structural and optoelectronic characteristics was systematically examined using various techniques, including x‐ray diffraction, UV–visible spectroscopy, Raman spectroscopy, and Hall effect measurements. To explore the structural characteristics, XRD measurements were performed, which confirm the FCC structure of nanocrystals. The optical property analysis suggested that the formation of the energy level can contribute to reduction of the band gap. A sharp peak at 397 cm−1 is associated with NiO bond in FTIR spectra which verifies the formation of nanocrystals. Moreover, the incorporation of K increases the intensity of the Raman peaks, which provides evidence for the higher degree of crystallinity in doped samples. These results of Raman scattering are in good agreement with XRD outcomes. In addition, the resistivity of NiO nanocrystals decreases monotonically with the increasing K concentration. The results of temperature‐dependent resistivity further demonstrate that electrons required more energy to jump from one polaron state to another in the case of x = 0.01 M and 0.03 M doped Ni0.5‐xKxO samples. The combination of a diminished band gap and enhanced conductivity makes these materials exceptionally promising for applications in optoelectronics and energy storage.

Enhancement of mechanical properties of natural rubber latex sheets by incorporating allyl-modified microcrystalline cellulose (AMCC)

Microcrystalline cellulose (MCC) was chemically modified with allyl bromide through the hydroxyl groups of cellulose to obtain allyl-modified microcrystalline cellulose (AMCC). To enhance the curing and mechanical properties of natural rubber latex, this AMCC was then compounded with a natural rubber latex formulation to produce rubber sheets. Unmodified MCC was also compounded and prepared into rubber sheets, which served as a reference. The formation of AMCC was confirmed using Fourier Transform Spectroscopy (FTIR). Furthermore, the thermal behavior of AMCC was examined by thermogravimetric analysis (TGA), and the degree of crystallinity before and after modification was evaluated by X-ray diffraction (XRD). The results of the rubber sheets showed that overall, maximum torque (MH), degree of crosslinking density, vulcanization rate (cure rate index), and tensile strength increased in AMCC-loaded rubber compared to MCC-loaded sheets. On the other hand, optimum cure time (t90) and elongation at break were lower in the AMCC-loaded rubber than in the MCC-loaded sheets. In overall, this method outlines a successful incorporation of modified cellulose into natural rubber-based products to obtain enhanced mechanical properties.

Poxylated stereocomplexes from PEtOx-b-PLA diblock copolymers

An ω-hydroxyl terminated poly(2-ethyl-2-oxazoline) (PEtOx) was obtained by termination of the cationic ring-opening polymerization of 2-ethyl-2-oxazoline with acetate and subsequent transesterification with methanol. The resulting PEtOx-OH featuring a degree of polymerization (DP) of 20 was used as a macroinitiator for the ring-opening polymerization of l-lactide as well as d-lactide. The resulting PEtOx-b-PLA block copolymers featured DP values of 25, 50, 100 and 150, respectively, and were characterized by means of size exclusion chromatography, 1H NMR spectroscopy as well as matrix-assisted laser desorption ionization mass spectrometry. Differential scanning calorimetry, wide-angle x-ray scattering and polarized light microscopy indicated the formation of stereocomplexes in racemic blends of PEtOx-b-PLA with opposing chirality. Thereby, the amorphous PEtOx block did not affect the modification of the stereocomplex crystallites, as shown by comparison with data obtained from PLA homopolymer stereocomplexes. Similar to those, the degree of crystallinity and melting temperature decreased with increasing molar mass of the PLA in the stereocomplexes formed from PEtOx-b-PLA block copolymers.

Chitosan-based gel polymer electrolytes for high performance Li-ion battery

This study explores the use of glutaraldehyde-crosslinked chitosan-based gel polymer electrolytes (GPEs) in lithium-ion batteries (LIBs). GPEs are prepared by solution casting using two different molecular weights of chitosan including 150 kDa as medium and 400 kDa as high molecular weight (MMWCS and HMWCS, respectively) with varying amounts of crosslinker. Degree of crystallinity was 25.9 and 24.1 % for HMWCS and MMWCS, respectively that was decreased to 18.3 and 22.7 % by using 5 % crosslinker and 17.8 and 21.1 % by using 10 % crosslinker, and 17.2 and 17.6 % by using 20 % crosslinker. The obtained ionic conductivity for HMWCS and MMWCS was 3.1 × 10−3 and 2.9 × 10−3 S.cm−1. After crosslinking by 5, 10, and 20 % crosslinker, the ionic conductivity was obtained to 0.9 × 10−3 and 0.3 × 10−3 S.cm−1, 6.3 × 10−3 and 5 × 10−3 S.cm−1, and 1.1 × 10−3 and 0.5 × 10−3 S.cm−1 for high and medium molecular weight, respectively. Lithium-ion transfer number was obtained between 0.34 and 0.83 and the highest t+ value was obtained for the MMWCS-GA10. Electrochemical stability window of the prepared polymer electrolytes was >5 V and samples showed no remarkable dendrite growth after cycling analyses. The symmetric cells demonstrated reliable performance, operating for over 300 h without any short-circuiting, which indicates excellent reversible cycling stability for chitosan-based lithium-ion batteries. Furthermore, the Gr/GPE cell exhibited very low voltage polarization, with the over-potential decreasing from 10 mV initially to 6 mV after 300 h at the same current density. Discharge capacity was obtained higher than 170 mAh/g at 0.2C with CE = 97 % for both HMWCS-GA20 and HMWCS-GA20.

Achieving an appropriate polarization-breakdown synergy of multilayer films for dielectric energy storage through temperature gradient annealing

Large polarization and high breakdown strength are the key to achieving an idea energy storage density in dielectric capacitors, but unfortunately the trade-off problem between them is difficult to evade, particularly for those dielectrics with different crystalline degrees. Herein, we propose an appropriate polarization-breakdown synergistic strategy of dielectric multilayer films through temperature gradient annealing. The dielectric properties of a serials of (Pb, La)(Zr, Ti)O3/SrTiO3/(Pb, La)(Zr, Ti)O3 (PLZT/STO/PLZT) structures with different annealing temperature for each layer are compared. The optimum recoverable energy density of 57.9 J/cm3 is achieved at a high breakdown electric field of 5.78 MV/cm and a moderate maximum polarization of 22.5 μC/cm2. In addition to the role of suppressing the carriers transport of interlayer STO, the balance between polarization and breakdown strength in bottom and top PLZT layers with individual dielectric characteristics should be responsible for the enhanced energy storage performance (ESP). The results suggest that it is a feasible way to optimize the ESP of dielectric multilayer films through designing different stacking layer via temperature gradient annealing heat treatment.

Dysprosium-Doped Glass-Ceramics From the System Na2O-Al2O3-SiO2-B2O3-Dy2O3.

Glasses from the system Na2O-Al2O3-SiO2-B2O3-Dy2O3 are prepared with three different concentrations of the Dy3+ ion-0.5, 1, and 2 at%. Glass-ceramics are obtained after thermal treatment of the parent glass at 580°С and 630°С during 2, 5, and 24 h. The crystallizing phases, the crystallinity degree, and the nano crystalline size are determined. The crystallizing phases after thermal treatment are NaAlSiO4 in two different modifications and Na3B3O6. XRD analyses show the presence of third unknown phase in some samples. Emission and excitation spectra of the glass-ceramics show the characteristic peaks of Dy3+ (4F9/2 → 6H15/2, 4F9/2 → 6H13/2 and 4F9/2 → 6H11/2 at 483, 575, and 668 nm, respectively). The yellow peak is dominating in all samples. The spectra show different intensity depending on the Dy3+ concentration, temperature, and time of the thermal treatment. This result suggests that the emission color can be controlled by these three factors.

Nanosilica/recycled polycarbonate composites for electronic packaging

Several simple methods were performed to recycle compact discs (CDs) using an alkaline solution. The hydrophilic silica nanoparticles were incorporated into the recycled deinked polycarbonate CDs, and these particles affected the dielectric, structure, and thermal properties of the recycled polycarbonates. The thermal properties of recycled CDs were studied by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). No significant change in the thermal stability of polycarbonate/silica nanocomposites was observed with the mechanical /chemical modifications. X-ray diffraction (XRD) revealed the structural aspects, showing a correlation between crystallinity, silica nanoparticles, and modification methods. The mechanically treated sample after chemical handling had the lowest degree of crystallinity (48%), showing that the modification methods enhanced the formation of the amorphous state, thus affecting its dielectric properties. Scanning electron microscopy (SEM) characterized the CD samples' microstructure and morphology. Finally, the dielectric properties were studied using broadband dielectric spectroscopy (BDS) in the 101 - 106 Hz range. The samples prepared using chemical and mechanical treatments were of low dielectric loss. This increases its importance when such samples are used as antistatic charge materials. For these reasons, recycled PC/SiO2 nanocomposites are recommended as effective packaging materials for electronic components.

Cellulose nanocrystal dispersion-ability in polylactides with various molecular weights prepared in dichloromethane/dimethyl sulfoxide solvents for electrospinning applications

In this study, effects of polylactide molecular weight, i.e., high (HPLA), medium (MPLA), low (LPLA), and dichloromethane (DCM)/dimethyl sulfoxide (DMSO) blend ratio on cellulose nanocrystal (CNC) dispersion quality in solution casted PLA/CNC nanocomposites were investigated via small amplitude oscillatory shear rheological analysis, while crystallization behavior, thermal degradation, morphological structure of the nanocomposites were also reported. Due to its low dielectric constant, none of the nanocomposites with 100DCM indicated a change in their complex viscosity as a result of poor CNC dispersion. This is while the increase in DMSO content (50%vv−1) improved CNC dispersion. The superior CNC dispersion-ability in PLAs with lower molecular weight was confirmed. The poorer CNC dispersion in HPLA attributes to hindering effect of higher molecular weight on solvent and nanoparticle diffusion. The better dispersed CNCs influenced crystal nucleation behavior of PLAs and increased crystallinity degree. In addition, the impact of well-dispersed CNCs on fiber formation quality of nanocomposites was reported. Introducing finely dispersed CNCs (1 wt%) in LPLA refined fiber diameters around 1200 nm with more homogenous structure. Besides, the use of 100DCM and the use of DMSO at high contents (50%vv−1) deteriorated fiber formation, respectively, due to low conductivity of DCM and high boiling temperature of DMSO.

Novel versatile 5-aminoisophthalic acid modified chitosan nanofiber pads for adsorption toward Congo red, methyl orange, crystal violet, and methylene blue

To structure novel nanofiber pads for organic dye removal from dye-polluted water, we previously prepared CSP nanofiber pads by chitosan (CS) and polyethylene oxide (PEO) via electrospinning, followed by preparation of CSRP nanofiber pads through partial PEO removal from CSP, and the subsequent fabrication of CS-A nanofiber pads via grafting 5-aminoisophthalic acid (5-AIPA) to CSRP. FTIR, XRD, and elemental analyses confirmed the successful synthesis of CS-A nanofiber pads (crosslinking and crystalline degrees of 36.64 % and 4.57 %). CS-A nanofiber pads had porous nanofiber structures (diameter and pore size of 153.46 and 3.82 nm), high specific surface area (102.06 m2/g), great thermal stability (total mass loss of 50.2 %), excellent hydrophilicity (water contact angle of 12.0°), superior swelling performance (2331 %), good pH stability (pH of 3.0–11.0), and 6.8 of pHpzc, evidenced by SEM, Brunauer-Emmett-Teller (BET), thermogravimetric (TG), differential thermogravimetric (DTG), wettability, swelling, and solid addition tests. Optimum adsorption parameters (e.g., pH, dosage, and initial concentration) were selected by batches of tests on adsorption toward four organic dyes. CS-A’s surfaces were heterogeneous, and the adsorption belonged to spontaneous endothermic chemical adsorption, confirmed by kinetic and isothermal models and thermodynamic results. CS-A nanofiber pads were of great reusability and easy to be separated. Adsorption mechanisms involved electrostatic attractions, hydrogen bondings, π-stacking interactions, and pore fillings. Dynamic adsorption toward Congo red showed the Thomas model well fitted the breakthrough curves (R2 > 0.9971), showing the maximum adsorption capacity of 949.15 mg/g. Totally, CS-A nanofiber pads were effective adsorbents suitable for organic dye-containing wastewater purification.

Crystallinity degree of MoSe 2 influencing its potassium-ion storage performance

Crystallinity degree of MoSe ₂ influencing its potassium-ion storage performance