Journal Description
Crystals
Crystals
is an international, peer-reviewed, open access journal on Crystallography published monthly online by MDPI. The Professional Committee of Key Materials and Technology for Electronic Components (PC-KMTEC) is affiliated with Crystals and its members receive discounts on the article processing charges.
- Open Access— free for readers, with article processing charges (APC) paid by authors or their institutions.
- High Visibility: indexed within Scopus, SCIE (Web of Science), Inspec, CAPlus / SciFinder, and other databases.
- Journal Rank: JCR - Q2 (Crystallography) / CiteScore - Q2 (Condensed Matter Physics)
- Rapid Publication: manuscripts are peer-reviewed and a first decision is provided to authors approximately 10.6 days after submission; acceptance to publication is undertaken in 2.7 days (median values for papers published in this journal in the second half of 2023).
- Recognition of Reviewers: reviewers who provide timely, thorough peer-review reports receive vouchers entitling them to a discount on the APC of their next publication in any MDPI journal, in appreciation of the work done.
Impact Factor:
2.7 (2022);
5-Year Impact Factor:
2.6 (2022)
Latest Articles
Morphological Study of Tetra-n-Butylammonium Bromide Semi-Clathrate Hydrate in Confined Space
Crystals 2024, 14(5), 408; https://doi.org/10.3390/cryst14050408 - 26 Apr 2024
Abstract
Tetra-n-butylammonium Bromide (TBAB) finds extensive use in diverse applications. An in-depth investigation into the effects of the formation conditions on TBAB hydrate is necessary to optimize the application process. This work focuses on examining the influence of the mass concentration of TBAB solution
[...] Read more.
Tetra-n-butylammonium Bromide (TBAB) finds extensive use in diverse applications. An in-depth investigation into the effects of the formation conditions on TBAB hydrate is necessary to optimize the application process. This work focuses on examining the influence of the mass concentration of TBAB solution and the cooling rate on TBAB hydrate formation through optical microscopy and Raman spectroscopy. The TBAB hydrate formation process occurs in a confined space created by an optical sheet with a 0.03 mm deep groove. Four TBAB solutions of 13. 8 wt%, 18 wt%, 32 wt%, and 40 wt% are investigated, and the supercooling required for hydrate nucleation increases with concentration at a cooling rate of 0.5 K/min. Notably, Type A TBAB hydrate preferentially forms in all of the solutions, although type B hydrate is thermodynamically stable in the two dilute solutions. At a larger cooling rate of 2 K/min, two distinct crystal growth patterns are observed: one controlled by mass transfer and the other regulated by heat transfer. Increasing the cooling rate not only alters the optical morphology, but also reduces the supercooling due to a decrease in the Gibbs free energy barrier caused by a larger temperature gradient. This is beneficial for practical applications as it helps to alleviate the supercooling degree.
Full article
(This article belongs to the Section Materials for Energy Applications)
Open AccessArticle
Research on Fe Removal, Regeneration Process, and Mechanical Properties of Mg Alloy AM50A
by
Zhao Chen, Changfa Zhou, Wenbo Liu, Sanxing Chen, Cong Gao, Shaowei Jia, Xiaowen Yu, Wang Zhou, Bolin Luo and Qingshuang Zhang
Crystals 2024, 14(5), 407; https://doi.org/10.3390/cryst14050407 - 26 Apr 2024
Abstract
In recent years, the widespread application of Mg alloy casting and Mg alloy products has generated a large amount of Mg alloy waste. This experiment used a single factor experimental analysis method to study the optimal process for removing Fe from Mg alloy
[...] Read more.
In recent years, the widespread application of Mg alloy casting and Mg alloy products has generated a large amount of Mg alloy waste. This experiment used a single factor experimental analysis method to study the optimal process for removing Fe from Mg alloy AM50A waste, and developed an efficient Fe removal and regeneration process for Mg alloy AM50A. It was found that the optimal refining temperature for removing Fe ions was 670 °C, the optimal refining (RJ-2) agent mass ratio was 1.5%, and the optimal refining time was 40 min. Regenerated J40-1.5-AM50A Mg alloy was prepared using the best refining process, and its composition and mechanical properties were tested and analyzed. The experimental results show that the composition of the regenerated J40-1.5-AM50A Mg alloy prepared by this method is consistent with AM50A, with an Fe removal rate of 96.2%. The mechanical properties were improved compared to the original AM50A sample, with a maximum tensile strength increase of 1.611 KN and a tensile strength increase of 26.333 MPa. The elongation after fracture is 2.25 times that of the original sample. Research has shown that the RJ-2 refining agent can provide mechanical properties of magnesium alloys during the refining process. By analyzing the composition, XRD, SEM, and EDS of AM50A (Fe) and J40-1.5-AM50A, it was found that the refining process accelerates the removal of Fe in the form of Fe deposition.
Full article
(This article belongs to the Special Issue Advanced Crystalline Materials, Mechanical Properties and Innovative Production Systems (2nd Edition))
Open AccessArticle
Luminescence and Electron–Hole-Trapping Centers in α-Ca2P2O7-Mn
by
Turlybek N. Nurakhmetov, Temirulan T. Alibay, Keleshek B. Zhangylyssov, Aibek S. Nurpeissov, Sapargali Pazylbek, Diana Griesiute, Aleksej Zarkov and Aivaras Kareiva
Crystals 2024, 14(5), 406; https://doi.org/10.3390/cryst14050406 - 26 Apr 2024
Abstract
The mechanisms of formation of induced intrinsic and impurity radiative states, which consist of intrinsic and impurity electron–hole-trapping center states in irradiated Ca2P2O7-Mn and Ca2P2O7 phosphates, were investigated using thermoactivation and vacuum-ultraviolet
[...] Read more.
The mechanisms of formation of induced intrinsic and impurity radiative states, which consist of intrinsic and impurity electron–hole-trapping center states in irradiated Ca2P2O7-Mn and Ca2P2O7 phosphates, were investigated using thermoactivation and vacuum-ultraviolet spectroscopy methods. These centers are excited at photon energies of 4.0 eV and 4.5 eV, which are within the matrix’s transparency region. New radiative-induced states at 3.06 eV and 2.92 eV are demonstrated to be generated upon the excitation of anions by photons with energies of 5.0 and 5.64 eV. This process is due to charge transfer from the ion to the impurities, specifically Mn2+(O2--Mn2+) and the neighboring ion O 2--(P2O7)4-. Furthermore, upon the excitation of matrix anions with photon energies exceeding the band gap (8.0–8.25 eV), electron-trapping by impurities such as Mn2+ and (P2O7)4- ions results.
Full article
(This article belongs to the Section Inorganic Crystalline Materials)
Open AccessArticle
Crystal Plasticity Finite Element Modeling of the Influences of Ultrafine-Grained Austenite on the Mechanical Response of a Medium-Mn Steel
by
Pengfei Shen, Yang Liu and Xiang Zhang
Crystals 2024, 14(5), 405; https://doi.org/10.3390/cryst14050405 - 26 Apr 2024
Abstract
Medium manganese (medium-Mn) steel, one of the third-generation advanced high-strength steels (AHSS), delivers impressive mechanical properties such as high yield strength, ultimate tensile strength, and uniform elongation. One notable feature of medium-Mn steels is the presence of ultrafine-grained (UFG) austenite, achieved through phase
[...] Read more.
Medium manganese (medium-Mn) steel, one of the third-generation advanced high-strength steels (AHSS), delivers impressive mechanical properties such as high yield strength, ultimate tensile strength, and uniform elongation. One notable feature of medium-Mn steels is the presence of ultrafine-grained (UFG) austenite, achieved through phase transformation from the parent martensite phase during intercritical annealing. While, in general, UFG is considered a strengthening mechanism, the impact of UFG austenites in medium-Mn steel has not been fully studied. In this manuscript, we advance our previous work on crystal plasticity simulation based on the Taylor model to consider fully resolved high-fidelity microstructures and systematically study the influence of the UFG austenites. The original microstructure with UFG is reconstructed from a set of serial electron backscatter diffraction (EBSD) scans, where the exact grain morphology, orientation, and phase composition are preserved. This microstructure was further analyzed to identify the UFG austenites and recover them to their parent martensite before the intercritical annealing. These two high-fidelity microstructures are used for a comparative study using dislocation density-based crystal plasticity finite modeling to understand the impact of UFG austenites on both the local and overall mechanical responses.
Full article
(This article belongs to the Special Issue Characterization and Modelling of the Deformation and Failure of Engineering Metallic Materials)
►▼
Show Figures
Figure 1
Open AccessReview
Toward Direct Exploration of the Few-Femtosecond Dynamics of Electronic Coherence and Correlation in Quantum Materials Using Time- and Angle-Resolved Photoemission Spectroscopy
by
Kai Rossnagel and Michael Bauer
Crystals 2024, 14(5), 404; https://doi.org/10.3390/cryst14050404 - 26 Apr 2024
Abstract
Over the last two decades, time- and angle-resolved photoemission spectroscopy (trARPES) has become a mature and established experimental technique for the study of ultrafast electronic and structural dynamics in materials. To date, most trARPES investigations have focused on the investigation of processes occurring
[...] Read more.
Over the last two decades, time- and angle-resolved photoemission spectroscopy (trARPES) has become a mature and established experimental technique for the study of ultrafast electronic and structural dynamics in materials. To date, most trARPES investigations have focused on the investigation of processes occurring on time scales of ≳30 fs, in particular, relaxation and thermalization, and have therefore been blind to the initial sub-10 fs dynamics related to electronic coherence and correlation effects. In this article, we illustrate how current trARPES setups reach their limits when it comes to addressing such extraordinarily short time scales and present an experimental configuration that provides the time, energy, and momentum resolutions required to monitor few-femtosecond dynamics on the relevant energy and momentum scales. We discuss the potential capabilities of such an experiment to study the electronic response of materials in the strong-field interaction regime at PHz frequencies and finally review a theoretical concept that may in the future even overcome the competing resolution limitations of trARPES experiments, as imposed by the time–bandwidth product of the probing laser pulse. Our roadmap for ultrafast trARPES indicates a path to break new experimental ground in quantum nonequilibrium electronic dynamics, from which new possibilities for ultrafast control of optical and electronic signals in quantum materials can be explored.
Full article
(This article belongs to the Special Issue Advanced Research of Silicon Photonics and Optoelectronics Devices)
►▼
Show Figures
Figure 1
Open AccessArticle
Screening of Complex Layered Chalcogenide Structures as High-Performance Thermoelectrics by High-Throughput Calculations
by
Jing Tian, Weiliang Ma, Manuela Carenzi, Pascal Boulet and Marie-Christine Record
Crystals 2024, 14(5), 403; https://doi.org/10.3390/cryst14050403 - 26 Apr 2024
Abstract
Thermoelectric materials have drawn much attention over the last two decades due to the increase in global energy demand. However, designing efficient thermoelectrics reveals itself as a tough task for their properties (Seebeck coefficient, electrical conductivity, thermal conductivity) are mutually opposed. Hence, most
[...] Read more.
Thermoelectric materials have drawn much attention over the last two decades due to the increase in global energy demand. However, designing efficient thermoelectrics reveals itself as a tough task for their properties (Seebeck coefficient, electrical conductivity, thermal conductivity) are mutually opposed. Hence, most recently, new design approaches have appeared, among which high-throughput methods have been implemented either experimentally or computationally. In this work, a high-throughput computer program has been designed to generate over 4000 structures based on a small set of complex layered chalcogenide compounds taken from the mAIVBVI nA2VB3VI homologous series, where AIV is Ge, AV is Sb and BVI is Te. The computer-generated structures have been investigated using density-functional theory methods, and the electronic and transport properties have been calculated. It has been found, using the quantum theory of atoms in molecules and crystals, that a wide variety of bond types constitutes the bonding network of the structures. All the structures are found to have negative formation energies. Among the obtained final structures, 43 are found with a wide band gap energy (>0.25 eV), 358 with semi-conductor/metal characteristics, and 731 with metallic characteristics. The transport properties calculations, using the Boltzmann equation, reveal that two p-type and 86 n-type structures are potentially promising compounds for thermoelectric applications.
Full article
(This article belongs to the Special Issue Research on Thermoelectric Materials: Waste Heat into Renewable Energy)
►▼
Show Figures
Figure 1
Open AccessArticle
Recognition of a Single β-D-Xylopyranose Molecule by Xylanase GH11 from Thermoanaerobacterium saccharolyticum
by
Ki Hyun Nam
Crystals 2024, 14(5), 402; https://doi.org/10.3390/cryst14050402 - 26 Apr 2024
Abstract
The endo-β-1,4-xylanase glycosyl hydrolase (GH11) decomposes the backbone of xylan into xylooligosaccharides or xylose. These enzymes are important for industrial applications in the production of biofuel, feed, food, and value-added materials. β-D-xylopyranose (XYP, also known as β-D-xylose) is the fundamental unit of the
[...] Read more.
The endo-β-1,4-xylanase glycosyl hydrolase (GH11) decomposes the backbone of xylan into xylooligosaccharides or xylose. These enzymes are important for industrial applications in the production of biofuel, feed, food, and value-added materials. β-D-xylopyranose (XYP, also known as β-D-xylose) is the fundamental unit of the substrate xylan, and understanding its recognition is fundamental for the initial steps of GH11’s molecular mechanism. However, little is known about the recognition of a single XYP molecule by GH11. In this study, the crystal structures of GH11 from Thermoanaerobacterium saccharolyticum (TsaGH11) complexed with an XYP molecule were determined at a resolution of 1.7–1.9 Å. The XYP molecule binds to subsite −2 of the substrate-binding cleft. The XYP molecule is mainly stabilized by a π–π interaction with the conserved Trp36 residue. The O2 and O3 atoms of XYP are stabilized by hydrogen bond interactions with the hydroxyl groups of Tyr96 and Tyr192. The conformation of the thumb domain of TsaGH11 does not play a critical role in XYP binding, and XYP binding induces a shift in the thumb domain of TsaGH11 toward the XYP molecule. A structural comparison of TsaGH11 with other GH11 xylanases revealed that the XYP molecule forms π–π stacking with the center between the phenyl and indoline ring of Trp36, whereas the XYP molecule unit from xylobiose or xylotetraose forms π–π stacking with the indoline of Trp36, which indicates that the binding modes of the substrate and XYP differ. These structural results provide a greater understanding of the recognition of XYP by the GH11 family.
Full article
(This article belongs to the Special Issue The Crystal Structure and Characteristics of Enzymes)
►▼
Show Figures
Figure 1
Open AccessArticle
Distinct Crystallization Pathways of Polyoxymethylene in Methanol System
by
Haowen Du, Xiaomeng Zhou, Yaru Zhang, Yang Ye, Shutian Xuanyuan, Sen Yang, Guorui Lao and Chuang Xie
Crystals 2024, 14(5), 401; https://doi.org/10.3390/cryst14050401 - 25 Apr 2024
Abstract
Recrystallization of polyoxymethylene (POM) in solvent is an effective post-treatment method for manufacturing a better POM product. Herein, the crystallization process of POM in methanol was investigated with the use of a series of equipment. The results reveal that POM crystallization in methanol
[...] Read more.
Recrystallization of polyoxymethylene (POM) in solvent is an effective post-treatment method for manufacturing a better POM product. Herein, the crystallization process of POM in methanol was investigated with the use of a series of equipment. The results reveal that POM crystallization in methanol yields two kinds of particle morphologies, including small particles with lamellar structures branching and growing in all directions and large particles resulting from melt agglomeration. The mechanism of POM crystallization in methanol with two distinct pathways was proposed, in which solution cooling crystallization of POM at higher temperature yields small particles while melt crystallization yields large particles. Furthermore, both non-isothermal and isothermal crystallization kinetics of POM were determined. The Avrami equation was employed to derive the crystallization rate constant via data fitting. The activation energy of crystallization was then obtained using the Arrhenius formula. The kinetics suggest that recrystallization of POM in methanol may dissolve and remove substances hindering raw material crystallization, achieving a faster crystallization rate for products.
Full article
(This article belongs to the Section Industrial Crystallization)
Open AccessArticle
Study on the Fabrication and Acoustic Properties of Near-Stoichiometric Lithium Tantalate Crystal Surface Acoustic Wave Filters
by
Jiashun Si, Xuefeng Xiao, Yan Huang, Yan Zhang, Shuaijie Liang, Qingyan Xu, Huan Zhang, Lingling Ma, Cui Yang and Xuefeng Zhang
Crystals 2024, 14(5), 400; https://doi.org/10.3390/cryst14050400 - 25 Apr 2024
Abstract
Near-stoichiometric lithium tantalate (NSLT) wafers with different Li contents were prepared by vapour transfer equilibrium (VTE) method and fabricated into surface acoustic wave filters. The temperature coefficient of frequency, insertion loss, and bandwidth of the surface acoustic wave filters were tested using a
[...] Read more.
Near-stoichiometric lithium tantalate (NSLT) wafers with different Li contents were prepared by vapour transfer equilibrium (VTE) method and fabricated into surface acoustic wave filters. The temperature coefficient of frequency, insertion loss, and bandwidth of the surface acoustic wave filters were tested using a special chip test bench and a network analyzer. The results show that the temperature coefficient of frequency shows a trend of first decreasing and then increasing with the increase in Li content, and the temperature stability of the surface acoustic wave filters is best when the Li content is 49.75%. It is also found that the surface acoustic wave filter fabricated from NSLT wafers has 21.18% lower temperature coefficient of frequency, 7.3% lower insertion loss, and 2.8% lower bandwidth than those fabricated from congruent lithium tantalate wafers. Therefore, NSLT crystals are more suitable for applications in acoustic devices, providing a new idea for performance enhancement of 5G communication devices.
Full article
(This article belongs to the Section Inorganic Crystalline Materials)
Open AccessArticle
Influence of MACl on the Crystallization Kinetics of Perovskite via a Two-Step Method
by
Chenyue Wang, Bingchen He, Meirong Fu, Zhenhuang Su, Liujiang Zhang, Junhan Zhang, Bingbao Mei and Xingyu Gao
Crystals 2024, 14(5), 399; https://doi.org/10.3390/cryst14050399 - 25 Apr 2024
Abstract
The addition of methylammonium chloride (MACl) significantly improves the performance and stability of perovskite fabricated by two-step processes. However, its role in crystallization dynamics has not been thoroughly studied. In this work, a comparison study is carried out using different additions of MACl
[...] Read more.
The addition of methylammonium chloride (MACl) significantly improves the performance and stability of perovskite fabricated by two-step processes. However, its role in crystallization dynamics has not been thoroughly studied. In this work, a comparison study is carried out using different additions of MACl to investigate the impact of the perovskite crystallization dynamics. In situ grazing incidence wide-angle X-ray scattering (GIWAXS) observations during the annealing process of perovskite revealed that the amount of MACl significantly influences the crystallinity and orientation of the perovskite. Increasing the MACl addition enhances the crystallinity of the perovskite in the wet film‘s intermediate phase and strengthens the out-of-plane orientation of the FAPbI3 perovskite α-phase (001) planes during annealing. Moreover, it was found that both excessive and insufficient amounts of MACl introduce defects into the perovskite, which are detrimental to device performance. In contrast, an optimal ratio of MACl-9 mg leads to the formation of uniform and large-grained FAPbI3 perovskite films, with the longest carrier lifetimes (163.7 ns) compared to MACl-5 mg (68.4 ns) and MACl- 13 mg (120.1 ns). As a result, the fabricated MACl-9 mg-based solar cell achieved the highest efficiency (22.63%), which is higher than those of MACl-5 mg (21.47%) and MACl-13 mg (20.07%).
Full article
(This article belongs to the Special Issue Progress and Prospects of Perovskite Films)
Open AccessArticle
From Batch to Continuous Small-Scale Production of Particles: Mixer Design Methodology for Robust Operation
by
Stefan Höving, Philipp Ronnewinkel and Norbert Kockmann
Crystals 2024, 14(5), 398; https://doi.org/10.3390/cryst14050398 - 25 Apr 2024
Abstract
Layered double hydroxides (LDHs) are a vital tool in many different areas, such as drug delivery, catalysis, anion exchange (materials), polymer processing, etc. Conventionally, LDHs are synthesized in a batch process that consists of particle generation and ripening, where product properties are manipulated
[...] Read more.
Layered double hydroxides (LDHs) are a vital tool in many different areas, such as drug delivery, catalysis, anion exchange (materials), polymer processing, etc. Conventionally, LDHs are synthesized in a batch process that consists of particle generation and ripening, where product properties are manipulated for stability and the optimal uptake of genetic material. Continuous processing and intensive mixing holds high promise for improved particle generation and characteristic control. In this contribution, an iterative method, using the mentioned particle generation as a use case, was applied to quickly generate a continuous process optimization platform for continuous, plugging-free particle generation with the required characteristics. Assisted by rapid prototyping and additive manufacturing, a vortex mixer was produced that delivers satisfactory long-term results.
Full article
(This article belongs to the Section Biomolecular Crystals)
►▼
Show Figures
Figure 1
Open AccessCommunication
Numerical Study on Monopole Production and Deconfinement Transition in Two-Condensate Charged Systems
by
Kai Kang, Jie Li, Guo Wang, Jiangning Zhang, Jiantao Che, Tianyi Han and Hai Huang
Crystals 2024, 14(5), 397; https://doi.org/10.3390/cryst14050397 - 25 Apr 2024
Abstract
The condensed matter Bose system may contain effective monopole quasiparticles in its excitation spectrum. In this paper, we first accomplish the mapping of the two-band Ginzburg–Landau theory to the extended CP1 model, and then perform the Monte Carlo simulations on the
[...] Read more.
The condensed matter Bose system may contain effective monopole quasiparticles in its excitation spectrum. In this paper, we first accomplish the mapping of the two-band Ginzburg–Landau theory to the extended CP1 model, and then perform the Monte Carlo simulations on the cubic lattice with periodic boundary conditions. With the numerical data of monopole density and magnetic susceptibility, we indicate that there exists a monopole–antimonopole deconfinement transition for the two-band superconducting system with the critical temperature above 70 K. We also suggest the possible detection of this new monopole plasma phase in high- iron-based superconductors.
Full article
(This article belongs to the Special Issue Superconductors and Magnetic Materials)
►▼
Show Figures
Figure 1
Open AccessArticle
Two 5-Methoxyindole Carboxylic Acid-Derived Hydrazones of Neuropharmacological Interest: Synthesis, Crystal Structure, and Chemiluminescent Study of Radical Scavenging Properties
by
Neda Anastassova, Nadya Hristova-Avakumova, Rusi Rusew, Boris Shivachev and Denitsa Yancheva
Crystals 2024, 14(5), 396; https://doi.org/10.3390/cryst14050396 - 25 Apr 2024
Abstract
Given the importance of molecular structure in pharmacological activity and interaction with biological receptors, we conducted a study on the 3,4-dihydroxybenzaldehyde hydrazone derivative of 5-methoxy-indole carboxylic acid (5MICA) and a newly synthesised analogue bearing a 2-methoxy-4-hydroxyphenyl ring using single-crystal X-ray diffraction. We studied
[...] Read more.
Given the importance of molecular structure in pharmacological activity and interaction with biological receptors, we conducted a study on the 3,4-dihydroxybenzaldehyde hydrazone derivative of 5-methoxy-indole carboxylic acid (5MICA) and a newly synthesised analogue bearing a 2-methoxy-4-hydroxyphenyl ring using single-crystal X-ray diffraction. We studied the ability of the two compounds to scavenge hypochlorite ions using luminol-enhanced chemiluminescence and their potential to modulate oxidative damage induced by iron on the biologically significant molecules lecithin and deoxyribose in order to evaluate possible antioxidant and prooxidant effects. The X-ray study revealed highly conserved geometry and limited rotation and deformation freedom of the respective indole and phenyl fragments. Interestingly, a conformational difference between the two independent molecules in the asymmetric unit of 3b was found. The X-ray study revealed a combination of hydrogen bonding interactions, short contacts, and π–π stacking stabilizing the specific three-dimensional packing of the molecules of 3a and 3b in the crystal structures. The three-dimensional packing of the molecules of 3b produced a zigzag layering projected along the c-axis. Both compounds effectively decreased luminol-dependent chemiluminescence in model systems with KO2-produced superoxide. They displayed opposite effects when applied in a xanthine/xanthine oxidase system. The hydrazones of 5MICA do not trigger a prooxidant effect or subsequent toxicity under conditions of iron-induced oxidative stress. The 3,4-dihydroxy-substituted derivative demonstrated excellent radical scavenging properties in all model systems, making it the lead compound for the development of compounds with combined neuroprotective and antioxidant properties.
Full article
(This article belongs to the Section Biomolecular Crystals)
►▼
Show Figures
Figure 1
Open AccessArticle
Insights into Early Phases of Phycocyanin Crystal Formation via SONICC Spectroscopy
by
Eugenia Pechkova, Paola Ghisellini, Stefano Fiordoro, Cristina Rando and Roberto Eggenhöffner
Crystals 2024, 14(5), 395; https://doi.org/10.3390/cryst14050395 - 25 Apr 2024
Abstract
This research delves into the early nucleation stages of phycocyanin, a protein pivotal for its fluorescent properties and crystalline stability and holding considerable potential for biotechnological applications. The paper contrasts traditional crystallization methods with the innovative Langmuir–Blodgett nanotemplate approach, aiming to enhance molecular
[...] Read more.
This research delves into the early nucleation stages of phycocyanin, a protein pivotal for its fluorescent properties and crystalline stability and holding considerable potential for biotechnological applications. The paper contrasts traditional crystallization methods with the innovative Langmuir–Blodgett nanotemplate approach, aiming to enhance molecular assembly and nucleation processes. The study employs Langmuir–Blodgett nanotemplates alongside second-order nonlinear imaging of chiral crystal (SONICC) spectroscopy. This combination is designed to orderly organize phycocyanin molecules and provide a sensitive visualization of early-stage crystal formation, capturing the intricate dynamics of protein crystallization. The experiments were conducted under controlled conditions, where surface pressure was maintained at 26 mN/m and barrier speed at 70 cm/min to optimize the monolayer formation at the air–water interface. The Langmuir–Blodgett method, compared to traditional vapor diffusion techniques, shows improvements in the uniformity and efficiency of nucleation. The sensitivity of SONICC spectroscopy significantly enhances the visualization of the nucleation process, revealing a more structured and uniform crystalline assembly in the early stages of formation. This method demonstrates a substantial improvement in nucleation dynamics, leading to a more orderly growth process and potentially larger, well-ordered crystals. Integrating Langmuir–Blodgett nanotemplates with SONICC spectroscopy offers a significant step in understanding protein crystallization processes with insights into the nucleation and growth of protein crystals and broad implications for refining crystallography methodologies of protein-based biomaterials, contributing to the advancement of structural biology and materials science.
Full article
(This article belongs to the Section Biomolecular Crystals)
►▼
Show Figures
Figure 1
Open AccessArticle
CO2 Promoting Polymorphic Transformation of Clarithromycin: Polymorph Characterization, Pathway Design, and Mechanism Study
by
Lixin Hou, Dingding Jing, Yanfeng Wang and Ying Bao
Crystals 2024, 14(5), 394; https://doi.org/10.3390/cryst14050394 - 24 Apr 2024
Abstract
Carbon dioxide (CO2) has a wide range of uses such as food additives and raw materials for synthetic chemicals, while its application in the solid-state transformation of pharmaceutical crystals is rare. In this work, we report a case of using 1
[...] Read more.
Carbon dioxide (CO2) has a wide range of uses such as food additives and raw materials for synthetic chemicals, while its application in the solid-state transformation of pharmaceutical crystals is rare. In this work, we report a case of using 1 atm CO2 as an accelerator to promote the polymorphic transformation of clarithromycin (CLA). Initially, crystal structures of Form 0′ and three solvates were successfully determined by single crystal X-ray diffraction (SCXRD) analysis for the first time and found to be isomorphous. Powder X-ray diffraction (PXRD) and thermal analysis indicated that the solvate desolvates and transforms into the structurally similar non-solvated Form 0′ at room temperature to ~50 °C. Form 0′ and Form II are monotropically related polymorphs with Form II being the most stable. Subsequently, the effect of CO2 on the transformation of CLA solvates to Form II was studied. The results show that CO2 can significantly facilitate the transformation of Form 0′ to Form II, despite no significant effect on the desolvation process. Finally, the molecular mechanism of CO2 promoting the polymorphic transformation was revealed by the combination of the measurement of adsorption capacity, theoretical calculations as well as crystal structure analysis. Based on the above results, a new pathway of preparing CLA Form II was designed: transform CLA solvates into Form 0′ in 1 atm air at 50 °C followed by the transformation of Form 0′ to Form II in 1 atm CO2 at 50 °C. This work provides a new idea for promoting the phase transformation of pharmaceutical crystals as well as a new scenario for the utilization of CO2.
Full article
(This article belongs to the Special Issue Polycrystalline Materials – from Design to (Micro)Structural Characterization and Applications)
►▼
Show Figures
Figure 1
Open AccessArticle
Effect of Precursors Concentrations on the Photocatalysis Performance Stability of Electrodeposited ZnO Nanorods and Their Robustness in Aqueous Environments
by
Abdullah S. Alshammari, Mansour Mohamed, Ziaul Raza Khan, Mohamed Bouzidi and Mohamed Gandouzi
Crystals 2024, 14(5), 393; https://doi.org/10.3390/cryst14050393 - 24 Apr 2024
Abstract
ZnO nanostructured materials have been widely utilized in several environmental depollution applications. In the current work, ZnO nanorods were grown using the electrodeposition method with different precursor concentrations. A variation in the dimensions of the nanorods grown with the different precursor concentrations was
[...] Read more.
ZnO nanostructured materials have been widely utilized in several environmental depollution applications. In the current work, ZnO nanorods were grown using the electrodeposition method with different precursor concentrations. A variation in the dimensions of the nanorods grown with the different precursor concentrations was noticed, as expected. The ability of the fabricated nanorods to remove water pollutants under UV irradiation and their photocatalytic performance stability was also evaluated over a prolonged period of time. Interestingly, the samples grown in different conditions exhibited different capabilities to maintain their morphology and their photocatalytic performance after they were kept in contaminated water for a long time. Moreover, some samples also were found to remain photocatalytically active for approximately 47% longer than other samples. These findings indicate that the performance stability of ZnO nanorods for pollutants removal and their robustness can be greatly improved by controlling their growth parameters, which will favorably impact the use of ZnO nanorods for water-treatment applications and their economic aspects.
Full article
(This article belongs to the Special Issue Metal Oxide Thin Films, Nanomaterials and Nanostructures)
►▼
Show Figures
Figure 1
Open AccessArticle
A Comparison of the Mechanisms and Activation Barriers for Ammonia Synthesis on Metal Nitrides (Ta3N5, Mn6N5, Fe3Mo3N, Co3Mo3N)
by
Constantinos D. Zeinalipour-Yazdi
Crystals 2024, 14(5), 392; https://doi.org/10.3390/cryst14050392 - 23 Apr 2024
Abstract
In this study we perform a comparison of the reaction mechanism and the activation barrier for the rate-determining step in various metal nitrides (Ta3N5, Mn6N5, Fe3Mo3N, Co3Mo3N)
[...] Read more.
In this study we perform a comparison of the reaction mechanism and the activation barrier for the rate-determining step in various metal nitrides (Ta3N5, Mn6N5, Fe3Mo3N, Co3Mo3N) for the ammonia synthesis reaction. The reactions are explained with simplified schematics and the energy profiles for the various reaction mechanisms are given in order to screen the catalytic activity of the catalysts for the ammonia synthesis reaction. We find that the catalytic activity ranks in the following order: Co3Mo3N > Fe3Mo3N > Ta3N5 > Mn6N5. We also find that the reaction mechanism proceeds either by a Langmuir–Hinshelwood and an Eley–Rideal/Mars–van Krevelen mechanism. This is an overview of about 10 years of computational research conducted to provide an overview of the progress established in this field of study.
Full article
(This article belongs to the Special Issue Synthesis and Characterization of Ammonia Synthesis Catalysts)
►▼
Show Figures
Figure 1
Open AccessArticle
Layered Structure Based on PANi and SiO2 to Absorb HPM to Protect Systems and Devices
by
Essameldin M. Sheta and Adrian T. Sutinjo
Crystals 2024, 14(5), 391; https://doi.org/10.3390/cryst14050391 - 23 Apr 2024
Abstract
A layered structure composed of polyaniline (PANI) and silicon dioxide (SiO2) is proposed in this article. It was developed to obtain ultra-wideband and high-power microwave absorption. Due to the high thermal stability of PANi and SiO2 above 400 °C, the
[...] Read more.
A layered structure composed of polyaniline (PANI) and silicon dioxide (SiO2) is proposed in this article. It was developed to obtain ultra-wideband and high-power microwave absorption. Due to the high thermal stability of PANi and SiO2 above 400 °C, the proposed structure is able to absorb high amounts of power. The electromagnetic behavior of the structure is examined by full-wave simulation to investigate its ability to absorb microwave frequencies ranging from 1 to 20 GHz under both normal and oblique incidences of electromagnetic waves. Recent studies have produced results with a limited absorption range and a less consistent angular incidence than the structure presently being examined. Also, the layer-by-layer deposition of thin film facilitates the manufacturing procedure. Furthermore, owing to the high thermal stability of the proposed structure, the absorption of high-power microwaves is superior to that of alternative methodologies.
Full article
(This article belongs to the Special Issue Metamaterials and Metasurfaces for Microwave and THz Applications)
►▼
Show Figures
Figure 1
Open AccessEditorial
III-Nitride Materials: Properties, Growth, and Applications
by
Yangfeng Li
Crystals 2024, 14(5), 390; https://doi.org/10.3390/cryst14050390 - 23 Apr 2024
Abstract
Since the activation of magnesium (Mg) in p-type gallium nitride (GaN) [...]
Full article
(This article belongs to the Special Issue III-Nitride Materials: Properties, Growth, and Applications)
Open AccessArticle
Design and Study of Composite Film Preparation Platform
by
Chao Li, Wenxin Li, Guangqin Wu, Guojin Chen, Junyi Wu, Niushan Zhang, Yusen Gan, Dongqi Zhang and Chang Chen
Crystals 2024, 14(5), 389; https://doi.org/10.3390/cryst14050389 - 23 Apr 2024
Abstract
This study aims to develop equipment for the preparation of composite films and successfully implement a film thickness prediction function. During the research process, we segmented the mechanical structure of the composite thin film preparation equipment into distinct modules, completed the structural design
[...] Read more.
This study aims to develop equipment for the preparation of composite films and successfully implement a film thickness prediction function. During the research process, we segmented the mechanical structure of the composite thin film preparation equipment into distinct modules, completed the structural design of the core module, and validated the stability of the process chamber, as well as the reasonableness of the strength and stiffness through simulation. Additionally, we devised a regression model for predicting the film thickness of composite films. The input features for the model included the sputtering air pressure, sputtering current, and sputtering time for magnetron sputtering process samples, as well as the evaporation volume and evaporation current for vacuum evaporation process samples. Simultaneously, the output features were the film thickness for both process samples. Subsequently, we established the designed composite film preparation equipment and conducted experimental verification. During the experiments, we successfully prepared Cr-Al composite films and utilized AFM for surface morphology analysis. The results confirmed the excellent performance of the Cr-Al composite films produced by the equipment, demonstrating the reliability of the equipment.
Full article
(This article belongs to the Special Issue Advances in Synthesis, Characterization, and Application of Thin Films)
►▼
Show Figures
Figure 1
Journal Menu
► ▼ Journal Menu-
- Crystals Home
- Aims & Scope
- Editorial Board
- Reviewer Board
- Topical Advisory Panel
- Instructions for Authors
- Special Issues
- Topics
- Sections & Collections
- Article Processing Charge
- Indexing & Archiving
- Editor’s Choice Articles
- Most Cited & Viewed
- Journal Statistics
- Journal History
- Journal Awards
- Society Collaborations
- Conferences
- Editorial Office
Journal Browser
► ▼ Journal BrowserHighly Accessed Articles
Latest Books
E-Mail Alert
News
10 April 2024
Meet Us at the 18th International Symposium on Macrocyclic and Supramolecular Chemistry, 6–10 May 2024, Hangzhou, China
Meet Us at the 18th International Symposium on Macrocyclic and Supramolecular Chemistry, 6–10 May 2024, Hangzhou, China
10 April 2024
Meet Us at the 2024 Spring Meeting of the European Materials Research Society (E-MRS), 27–31 May 2024, Strasbourg, France
Meet Us at the 2024 Spring Meeting of the European Materials Research Society (E-MRS), 27–31 May 2024, Strasbourg, France
Topics
Topic in
Applied Sciences, Crystals, J. Compos. Sci., Materials, Metals
Modern Material Technologies Intended for Industrial Applications
Topic Editors: Tomasz Tański, Andrzej N. Wieczorek, Marcin StaszukDeadline: 30 June 2024
Topic in
Catalysts, Coatings, Crystals, Energies, Materials, Nanomaterials
Interfacial Bonding Design and Applications in Structural and Functional Materials
Topic Editors: Junlei Qi, Pengcheng Wang, Yaotian YanDeadline: 20 July 2024
Topic in
Crystals, Mathematics, Symmetry, Fractal Fract, Axioms
Mathematical Applications of Nonlinear Wave Properties in Crystalline and Dispersive Media
Topic Editors: Mahmoud A.E. Abdelrahman, Emad El-ShewyDeadline: 31 August 2024
Topic in
Acoustics, Crystals, Designs, Environments, Sustainability
Towards Sustainable and Liveable Cities: Recent Advances in Noise Control Measures
Topic Editors: Heow Pueh Lee, Linus Yinn Leng AngDeadline: 30 September 2024
Conferences
Special Issues
Special Issue in
Crystals
Advanced Nanomaterials for Thermal Energy Storage Applications
Guest Editors: C. Selvam, Sivasankaran Harish, S. ManikandanDeadline: 30 April 2024
Special Issue in
Crystals
Hot Corrosion and Oxidation of Alloys
Guest Editors: Marzena Mitoraj-Królikowska, Marcela E. Trybula, James L. SmialekDeadline: 20 May 2024
Special Issue in
Crystals
Wide Bandgap Semiconductor: GaN and SiC Material and Device
Guest Editors: Hao-chung Kuo, Chun-Hsiung Lin, Kung-Yen LeeDeadline: 30 May 2024
Special Issue in
Crystals
Advances in Low-Dimensional Materials for Electronics and Sensing Applications
Guest Editors: Hu Li, Klaus LeiferDeadline: 20 June 2024
Topical Collections
Topical Collection in
Crystals
Reviews in Liquid Crystals
Collection Editors: Vladimir Chigrinov, Aleksey Kudreyko
Topical Collection in
Crystals
Research on REBCO Films and Conductors
Collection Editors: Pablo Cayado, Jens Hänisch, Hannes Rijckaert