Crystallization Of Nanoparticles Research Articles

Synthesis of seawater-derived superhydrophobic calcium carbonate via CO2 mineralization by utilizing L-Arginine/L-Lysine oleate-based self-assembly structures

Superhydrophobic materials have been gaining popularity owing to their self-cleaning, anti-freezing, and anti-corrosion properties. This study presents an approach for the synthesis of superhydrophobic calcium carbonate via CO2 mineralization using carbon capture utilization (CCU) technology. By using biodegradable amino acids (L-arginine/L-lysine) and oleic acid, various biosurfactant self-assembly structures were formed as surface-modifying agents of calcium carbonate owing to the saponification and lyotropic phase transition. Moreover, calcium cations were recovered from salt-farm wastewater using pH-swing ion separation for sustainability and waste management. we presented various self-assembly structures depending on the ratio of amino acids to oleic acid, such as spherical micelles, liquid crystal nanoparticles, and vesicles for L-arginine oleate and spherical micelles, cylindrical micelles, and planar lamellar structures for L-lysine oleate. The synthesized calcium carbonates were 87.95 % purified scalenohedral calcite under micellar L-arginine oleate and 87.08 % purified spherical calcite under micellar L-lysine. Moreover, their surface areas were 28.85 m2/g for L-arginine and 13.46 m2/g for L-lysine. They were significantly improved and larger than that of commercial calcium carbonate (3.45 m2/g). In comparison, larger agglomerated calcite particles were produced under the other self-assembled structures. During mineralization, the amount of calcium oleate adsorbed on the surface of calcium carbonate played a crucial role in particle formation. Notably, superhydrophobic calcium carbonates were synthesized with a contact angle of 168.66° under spherical micelles of L-arginine oleate and 167.46° under spherical micelles of L-lysine oleate. The in-situ surface modification method utilizing biosurfactant self-assembled structures was expected to revitalize the carbon capture and utilization.

In situ one step growth of amorphous tin oxide electron transport layer for high-performance perovskite solar cells.

Tin oxide used in electron transport layer (ETL) exhibits key role in transmitting electrons and blocking holes in perovskite solar cells (PSCs) device. However, crystal tin oxide nanoparticles (NPs) become necessary to form SnO2 film by method of spin-coating, resulting in possible surface defect and cracks among SnO2 NPs, corresponding to unsatisfied performance PSCs. Herein, an amorphous tin oxide thin film is creatively in situ grew onto Fluorine-doped Tin Oxide (FTO) substrate as ETL. The designed solar cell device with structure of FTO/SnO2/MAPbI3/Sprio-OMeTAD/Ag owns a champion photoelectric conversion efficiency (PCE) up to 17.64%, 76.20% of filling coefficient (FF), and 1.09 V of open-circuit voltage (Voc), in comparing with 16.43%, 64.35% and 1.05 V for control group (crystal tin oxide as ETL), respectively. Besides, the champion device keeps 83.33% of initial PCE under nitrogen (N2) condition for one month, in comparison with 76.09% for control group. This work provides a viable strategy for facile preparing amorphous tin oxide film based ETL in perovskite solar cells.

Influence of nano-crystallization on Li-ion conductivity in glass Li$$_3$$PS$$_4$$: a molecular dynamics study

AbstractUnderstanding the ionic conduction mechanisms in solid electrolyte glasses and glass-ceramics is an important task for improving the performance of next-generation all-solid-state batteries. Although many ionic conduction mechanisms have been proposed, the mechanism of increased ionic conductivity in partially crystallized glass is not fully understood. In this study, molecular dynamics was used to analyze the strain and local ion mobility in the glass around the crystal nano-particles of Li$$_3$$ 3 PS$$_4$$ 4 , which is a promising material for solid electrolytes. From the analysis of the results, we find that a local strain field is generated around the crystal particles and that the tensile strain field decreases the activation energy of ion migration and increases the ionic conductivity. This study opens the possibility of improving the ionic conductivity of glass-ceramics by controlling crystallization and dispersing the tensile strain field, even though the crystalline phase is not a high ionic conducting phase.

Superior photoluminescence of quantum dot displays via organic-inorganic composite scatterers

High color purity of quantum dot organic light-emitting diodes (QD-OLEDs) can be achieved by blue OLED light to stimulate pixelized green and red QDs within a color conversion layer, providing high color conversion efficiency in commercialized displays. However, enhancing external quantum efficiency (EQE) and minimizing blue light leakage remain significant challenges. To resolve these issues, we have developed an organic-inorganic composite system comprising quantum dots (QDs), liquid crystal (LC), polymer, and inorganic nanoparticles, like titanium dioxide (TiO2). The best EQE was enhanced by ∼81.9% when TiO2 of 6 wt%. More importantly, the EQE was enhanced by ∼58.6% when TiO2 of 3 wt% while TiO2 nanoparticles were well-dispersed and stable without aggregation for more than 3 days, which is crucial for preventing nozzle blockages during inkjet printing in manufacturing processes. We believe our innovative approach is promising for boosting color conversion efficiency by exciting highly concentrated green and red QDs with blue light while also overcoming inherent fabrication hurdles associated with high concentrations of inorganic scatterers.

Lipid Nanocarriers-Enabled Delivery of Antibiotics and Antimicrobial Adjuvants to Overcome Bacterial Biofilms.

The opportunistic bacteria growing in biofilms play a decisive role in the pathogenesis of chronic infectious diseases. Biofilm-dwelling bacteria behave differently than planktonic bacteria and are likely to increase resistance and tolerance to antimicrobial therapeutics. Antimicrobial adjuvants have emerged as a promising strategy to combat antimicrobial resistance (AMR) and restore the efficacy of existing antibiotics. A combination of antibiotics and potential antimicrobial adjuvants, (e.g., extracellular polymeric substance (EPS)-degrading enzymes and quorum sensing inhibitors (QSI) can improve the effects of antibiotics and potentially reduce bacterial resistance). In addition, encapsulation of antimicrobials within nanoparticulate systems can improve their stability and their delivery into biofilms. Lipid nanocarriers (LNCs) have been established as having the potential to improve the efficacy of existing antibiotics in combination with antimicrobial adjuvants. Among them, liquid crystal nanoparticles (LCNPs), liposomes, solid lipid nanoparticles (SLNs), and nanostructured lipid carriers (NLCs) are promising due to their superior properties compared to traditional formulations, including their greater biocompatibility, higher drug loading capacity, drug protection from chemical or enzymatic degradation, controlled drug release, targeted delivery, ease of preparation, and scale-up feasibility. This article reviews the recent advances in developing various LNCs to co-deliver some well-studied antimicrobial adjuvants combined with antibiotics from different classes. The efficacy of various combination treatments is compared against bacterial biofilms, and synergistic therapeutics that deserve further investigation are also highlighted. This review identifies promising LNCs for the delivery of combination therapies that are in recent development. It discusses how LNC-enabled co-delivery of antibiotics and adjuvants can advance current clinical antimicrobial treatments, leading to innovative products, enabling the reuse of antibiotics, and providing opportunities for saving millions of lives from bacterial infections.

Niacin-Loaded Liquid Crystal Nanoparticles Ameliorate Prostaglandin D2-Mediated Niacin-Induced Flushing and Hepatotoxicity

Niacin-Loaded Liquid Crystal Nanoparticles Ameliorate Prostaglandin D2-Mediated Niacin-Induced Flushing and Hepatotoxicity

Rheological Properties Study of Polymer Dispersed Liquid Crystals Doped by SiO2 Nanoparticles

The present report discusses the development of a novel nano-composite using a polymer dispersed liquid crystal (PDLC) and inorganic silicon dioxide (SiO2) nanoparticles. The aim of this work was to investigate the effect of the SiO2 nanoparticles on the rheological properties of the PDLC films. In our research described in this paper SiO2 nanoparticle-doped polymer dispersed liquid crystal films were made from a mixture of ethylene glycol phenyl ether methacrylate (EGPEMA) pre-polymer, 4-Cyano-4′-pentylbiphenyl (5CB) liquid crystals (LC) and SiO2 nanoparticles by the polymerization induced phase separation (PIPS) process. Doping the PDLC systems with SiO2 improved the rheological properties of these materials; the percolation (network formation) observed reflected the good interfacial adhesion between the nanoparticles, the polymer matrix and the LC. On the other hand, a decrease in the storage modulus (G′) and loss modulus (G″) of the PDLC systems after addition of the SiO2 nanoparticles confirmed their high flexibility and low crystallinity. A slight increase in G′ at 0.05 wt.% SiO2 resulted in the good mechanical strength of the doped PDLC. The viscoelastic behavior of the doped and undoped PDLC systems was confirmed at high frequencies. Thermal characterization by differential scanning calorimetry (DSC) showed a decrease in the glass transition temperature (Tg) of the PDLC with 0.05 wt.% of SiO2 nanoparticles, which showed that we had a more flexible material.

Theoretical study of the nematic to isotropic phase transition in the mixtures of nematic liquid crystal and quantum dots nanoparticles

ABSTRACTThe nematic to isotropic phase transition in the mixtures of nematic liquid crystal and quantum dots nanoparticles has been studied. Flory Huggins theory of isotropic mixing and Landau-de Gennes theory have been used to study the nematic to isotropic phase transition. The effects of quantum dots nanoparticles on the nematic order parameter, transition temperature, and splay elastic constant have been discussed. The decrease of nematic order parameter, transition temperature, and splay elastic constant with the increase in volume fraction of quantum dots nanoparticles has been observed.

Enhancing persulfate activation by carbon − based Mn − Fe nanoparticles for groundwater ISCO treatment: Efficiency, stability and mechanism

Persulfate − based in situ chemical oxidation (ISCO) is a promising approach for groundwater treatment due to its potential. However, the development of catalysts with sufficient activity and stability in persulfate oxidation remains a long − term goal. In this study, we aimed to address this challenge by preparing bimetallic nanoparticles coated with porous nitrogen − doped graphene shells, known as MnFe − NC, to activate peroxydisulfate (PDS). The unique structural feature of MnFe − NC, with metallic crystal nanoparticles encapsulated in carbon shells, ensured excellent persulfate activation performance of MnFe − NC, even during repeated cycles and extended periods of storage. To evaluate the practical application of MnFe − NC, MnFe − NC/PDS was installed in sand columns for the ISCO of sulpiride (SPR), achieving removal efficiencies of approximately 100 % during a continuous 7 − day reaction process. MnFe − NC/PDS exhibited remarkable tolerance to pH changes and environmental interference commonly encountered in groundwater treatment scenarios. Combined with density functional theory calculations, Mn5C2 and Fe2N were identified as the key active site for MnFe − NC activation of PDS. The decomposition mechanism of SPR in the system was further analyzed, including the cleavage of C–N/C–C, denitration reaction, and substitution reaction. These findings provide important insights into the intricate processes involved in the degradation of refractory organic pollutants. The developed MnFe − NC catalyst for PDS − based ISCO exhibits great potential in the remediation of refractory organic pollutant − contaminated groundwater.

Preparation and characterization of glyceryl dibehenate and glyceryl monostearate -based lyotropic liquid crystal nanoparticles as carriers for hydrophobic drugs

Preparation and characterization of glyceryl dibehenate and glyceryl monostearate -based lyotropic liquid crystal nanoparticles as carriers for hydrophobic drugs

Chemical Synthesis of a Polyvinylpyrrolidone-Capped Silver Nanoparticle and Its Antimicrobial Activity against Two Multidrug-ResistantAeromonas Species

This study investigated the antimicrobial activity of polyvinylpyrrolidone-capped silver nanoparticles (PVP-AgNPs) in vitro against two antibiotic-resistant isolates of Aeromonas hydrophila and A. caviae. Solid crystal silver nanoparticles were synthesized by the chemical reduction approach employing polyvinylpyrrolidone (PVP) as a neutral stabilizer, glucose as a reducing agent, and sodium hydroxide as a catalyst. The crystallinity and purity of the prepared PVP-AgNPs were investigated using the X-ray diffraction spectrometer (XRD). Transmission electron micrograph analysis demonstrated the formation of irregular spherical shapes PVP-AgNPs with average crystallite size diameters ranging from 5.07 to 9.74 nm. By phenotypic and gene sequence analysis, A. hydrophila and A. caviae isolates were identified from diseased Nile tilapia. Our findings showed that all A. hydrophila and A. caviae isolates were multidrug-resistant (MDR) and showed resistance to four antimicrobial classes. The PVP-AgNPs displayed 15 mm and 14 mm clear inhibition zones for A. hydrophila and A. caviae, respectively. In addition, the minimum inhibitory concentrations for PVP-AgNPs were estimated to be 6.25 μg/ml and 7.5 μg/ml for A. hydrophila and A. caviae, respectively. The chemically synthesized PVP-AgNPs were found to possess a strong antimicrobial effect against A. hydrophila and A. caviae with the possibility to be used as a commercialized antimicrobial agent in the aquaculture industry.

Influence of composite mixtures between nematic liquid crystal and porous carbon nanoparticles towards photoluminescence and UV absorbance

Influence of composite mixtures between nematic liquid crystal and porous carbon nanoparticles towards photoluminescence and UV absorbance

Nanoparticle localization within chiral liquid crystal defect lines and nanoparticle interactions.

Self-assembly of colloidal particles into predefined structures is a promising way to design inexpensive manmade materials with advanced macroscopic properties. Doping of nematic liquid crystals (LCs) with nanoparticles has a series of advantages in addressing these grand scientific and engineering challenges. It also provides a very rich soft matter platform for the discovery of unique condensed matter phases. The LC host naturally allows the realization of diverse anisotropic interparticle interactions, enriched by the spontaneous alignment of anisotropic particles due to the boundary conditions of the LC director. Here we demonstrate theoretically and experimentally that the ability of LC media to host topological defect lines can be used as a tool to probe the behavior of individual nanoparticles as well as effective interactions between them. LC defect lines irreversibly trap nanoparticles enabling controlled particle movement along the defect line with the use of a laser tweezer. Minimization of Landau-de Gennes free energy reveals a sensitivity of the ensuing effective nanoparticle interaction to the shape of the particle, surface anchoring strength, and temperature, which determine not only the strength of the interaction but also its repulsive or attractive character. Theoretical results are supported qualitatively by experimental observations. This work may pave the way toward designing controlled linear assemblies as well as one-dimensional crystals of nanoparticles such as gold nanorods or quantum dots with tunable interparticle spacing.

Preparation of reverse mode polymer dispersion liquid crystals with vertically oriented layers and the electro-optical properties

ABSTRACT The reverse-mode polymer dispersed liquid crystals (re-mode PDLC) are feasible to be prepared by polyimide vertically oriented layers. The indium tin oxide (ITO) glass coated with polyimide-oriented layer was prepared by centrifugal spin coating and high temperature curing, and the re-mode PDLC film was prepared by polymerisation-induced phase separation method. After that the effects of diluent, negative liquid crystal and gadolinium oxide (Gd2O3) nanoparticle content on the morphology and electro-optical properties of re-mode PDLC were comprehensively investigated. The results show that the re-mode PDLC with appropriate diluent and negative liquid crystal content has stable contrast ratio and driving voltage, and the re-mode PDLC samples doped with Gd2O3 nanoparticles can further increase the contrast ratio to improve the problem of low contrast of ordinary re-mode PDLC samples. In the thermal ageing life test, the driving voltage ageing degree of the nanoparticle-doped re-mode PDLC samples can be stabilised, which has some significance for use of re-mode PDLC.

Oxidation of metallic Cu by supercritical CO2 and control synthesis of amorphous nano-metal catalysts for CO2 electroreduction

Amorphous nano-metal catalysts often exhibit appealing catalytic properties, because the intrinsic linear scaling relationship can be broken. However, accurate control synthesis of amorphous nano-metal catalysts with desired size and morphology is a challenge. In this work, we discover that Cu(0) could be oxidized to amorphous CuxO species by supercritical CO2. The formation process of the amorphous CuxO is elucidated with the aid of machine learning. Based on this finding, a method to prepare Cu nanoparticles with an amorphous shell is proposed by supercritical CO2 treatment followed by electroreduction. The unique feature of this method is that the size of the particles with amorphous shell can be easily controlled because their size depends on that of the original crystal Cu nanoparticles. Moreover, the thickness of the amorphous shell can be easily controlled by CO2 pressure and/or treatment time. The obtained amorphous Cu shell exhibits high selectivity for C2+ products with the Faradaic efficiency of 84% and current density of 320 mA cm−2. Especially, the FE of C2+ oxygenates can reach up to 65.3 %, which is different obviously from the crystalline Cu catalysts.

Role of biochar-based catalysts in microwave-induced biomass pyrolysis: Structural properties and modification with Fe-series metals

Biochar-based catalysts have great potential for microwave-induced biomass pyrolysis due to the combination of their excellent microwave absorption performance, good porous structure, and high catalytic activity. In this work, the potential of biochar-based catalysts for microwave-induced catalytic biomass pyrolysis to produce gaseous fuel and upgrade bio-oil was explored and the role of the structural characteristics and Fe-series modification was revealed. The results indicated that the catalytic performance of pure biochar was influenced by their microstructures, and the KOH-activated biochar with abundant microporous structures could effectively promote the gas yields from biomass pyrolysis under microwave heating conditions. With the loading of Fe0 crystal nanoparticles on biochar, the catalytic activity of biochar was greatly enhanced, resulting in an increase in combustible gas (CO, H2 and CH4) yield by 50 % compared to pure biochar, reaching 502.09 mL/g at 650 °C, as well as significant simplification of the bio-oil. Furthermore, the Fe-series alloy crystals exhibit superior catalytic activity over Fe0, further improving gas yields and promoting bio-oil upgrading. The biochar loading of Fe0.64Ni0.36 nanoparticles resulted in a combustible gas yield as high as 574.84 mL/g, and the production of hydrocarbons was greatly enhanced, with a high relative content of 33.9 % in bio-oil. Biochar-based CoFe nanoparticles promoted selective production of H2, with a yield as high as 230.84 mL/g, and the content of mono-phenols in the bio-oil was improved to 74.0 % with the composition of a high phenol relative content of 17.508 %, a trans-isoeugenol relative content of 17.260 %, and a guaiacol relative content of 12.780 %.

Liquid Crystal@Nanosilver Catalytic Amplification-Aptamer Trimode Biosensor for Trace Pb2.

Liquid crystals (LCs) are a very important display material. However, the use of LC, especially LC-loaded nanoparticles, as a catalyst to amplify the analytical signal and coupled with specific aptamer (Apt) as a recognition element to construct a highly sensitive and selective three-mode molecular spectral assay is rarely reported. In this article, five LCs, such as cholesteryl benzoate (CB), were studied by molecular spectroscopy to indicate the liquid crystal nanoparticles in the system, and highly catalytic and stable CB loaded-nanosilver (CB@AgNPs) sol was prepared. The slope procedure was used to study the catalysis of the five LCs and CB@AgNPs on the new indicator reaction between AgNO3 and sodium formate (Fo) to produce silver nanoparticles (AgNPs) with a strong surface plasmon resonance absorption (Abs) peak at 450 nm, a resonance Rayleigh scattering (RRS) peak at 370 nm and a surface enhanced Raman scattering (SERS) peak at 1618 cm-1 in the presence of molecular probes. By coupling the new CB@AgNPs catalytic indicator reaction with the Apt reaction, a new CB@AgNPs catalytic amplification-SERS/RRS/Abs trimode biosensoring platform was constructed for detecting inorganic pollutants, such as Pb2+, Cd2+, Hg2+ and As3+.

Development of amoxicillin Trihydrate-Loaded lyotropic liquid crystal nanoparticles for skin infection

Bacterial infections are growing rapidly and are considered as a key public health concern in recent years. Antibacterial agents are generally preferred for the treatment of bacterial infections. However, available treatment options need to be addressed for better therapeutic effectiveness. Lyotropic liquid crystal nanoparticles are one of the novel nanocarrier systems which can be used to load hydrophilic and hydrophobic drugs. In the current study, amoxicillin trihydrate-laden lyotropic liquid crystal nanoparticles were fabricated by the emulsification technique. The formulation showed particle size and PDI<200 nm and 0.3, respectively. The entrapment efficiency was found to be about 94.76 ± 0.27 %. The morphological characterization was studied by Cryo-SEM and it showed a smooth surface with a spherical shape. In addition, the in vitro release was performed in pH 6.8 phosphate buffer using a dialysis membrane. The drug-loaded lyotropic liquid crystal nanoparticle gel exhibited sustained release behavior and attained 90 % of release in 24 h. The zone of inhibition study was done against Staphylococcus aureus. The stability data showed promising results, and the nanoparticles were found to be stable over a period of two months. Moreover, MTT assay on human dermal fibroblast cells suggests that amoxicillin trihydrate-loaded lyotropic liquid crystal nanoparticles are as safe as amoxicillin trihydrate solution and are thus non-toxic and biocompatible. As a whole, it can be concluded that lyotropic liquid crystal nanoparticles might be one of the potential nanocarriers for the loading of amoxicillin trihydrate and could be used with to treat superficial bacterial skin infections.

Lipid Liquid Crystal Nanoparticles: Promising Photosensitizer Carriers for the Treatment of Infected Cutaneous Wounds.

Cutaneous chronic wounds impose a silent pandemic that affects the lives of millions worldwide. The delayed healing process is usually complicated by opportunistic bacteria that infect wounds. Staphylococcus aureus is one of the most prevalent bacteria in infected cutaneous wounds, with the ability to form antibiotic-resistant biofilms. Recently, we have demonstrated the potential of gallium protoporphyrin lipid liquid crystalline nanoparticles (GaPP-LCNP) as a photosensitizer against S. aureus biofilms in vitro. Herein, we investigate the potential of GaPP-LCNP using a pre-clinical model of infected cutaneous wounds. GaPP-LCNP showed superior antibacterial activity compared to unformulated GaPP, reducing biofilm bacterial viability by 5.5 log10 compared to 2.5 log10 in an ex vivo model, and reducing bacterial viability by 1 log10 in vivo, while unformulated GaPP failed to reduce bacterial burden. Furthermore, GaPP-LCNP significantly promoted wound healing through reduction in the bacterial burden and improved early collagen deposition. These findings pave the way for future pre-clinical investigation and treatment optimizations to translate GaPP-LCNP towards clinical application.

Coverage-dependent adsorption and dissociation of H2O on Al surfaces.

The adsorption and dissociation of H2O on Al surfaces including crystal planes and nanoparticles (ANPs) are systematically investigated by using density functional theory (DFT) calculations. H2O adsorption strength follows the order ANPs > Al(110) > Al(111) > Al(100). Due to the smaller cluster deformation caused by the moderate H2O adsorption, the relative magnitude of H2O adsorption strength on ANPs and crystal planes is opposite to the trend of adatoms like O* and/or N*. The energy barrier for the decomposition of H2O into H* and OH* is larger on ANPs than on crystal planes, and it decreases with the increasing cluster size. Due to the competition between the hydrogen (H) bonding among water molecules and the interaction between the water molecules and the substrate, the adsorption strength of H2O first increases and then decreases with the increase of water coverage. Moreover, each H2O molecule can efficiently form up to two H bonds with two H2O molecules. As a result, H2O molecules tend to aggregate into cyclic structures rather than chains on Al surfaces. Furthermore, the dissociation energy barrier of H2O drops with the increasing water coverage due to the presence of H bonds. Our results provide insight into interactions between water and Al, which can be extended to understand the interaction between water and other metal surfaces.