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Crystallographic analysis relies on the scattering of quanta from arrays of atoms that populate a repeating lattice. While large crystals built of lattices that appear ideal are sought after by crystallographers, imperfections are the norm for molecular crystals. Additionally, advanced X-ray and electron diffraction techniques, used for crystallography, have opened the possibility of interrogating micro- and nanoscale crystals, with edges only millions or even thousands of molecules long. These crystals exist in a size regime that approximates the lower bounds for traditional models of crystal nonuniformity and imperfection. Accordingly, data generated by diffraction from both X-rays and electrons show increased complexity and are more challenging to conventionally model. New approaches in serial crystallography and spatially resolved electron diffraction mapping are changing this paradigm by better accounting for variability within and between crystals. The intersection of these methods presents an opportunity for a more comprehensive understanding of the structure and properties of nanocrystalline materials.

Due to their poor solubility and poor bioavailability, the majority of recently produced novel chemical entities pose significant challenges in the formulation and development of new dosage forms. The pharmaceuticals in Biopharmaceutical Classification System (BCS) classes II and IV have a solubility issue; nanotechnology is the most effective solution to this issue. The preparation of nanocrystals and the numerous methods utilized to create them are the major topics of this review article. Since there is no matrix material present in drug nanocrystals, they are a carrier-free form of drug delivery. For pharmaceuticals in BCS classes II and IV, nanocrystal technologies have been suggested as beneficial, all-purpose formulation methods. The dissolving rate and saturation solubility of active agent can be efficiently increased by nanocrystals because of their higher surface to volume ratio. Major used routes of administration, including oral, IV, SC, IM, and topical administration are acceptable for the nanocrystals drug delivery system. For use in sterile products, nanocrystals can also be added to tablets, capsules, quick melts, and lyophilized materials. Precipitation, milling, high pressure homogenization, and combination methods like Nano-EdgeTM, SmartCrystal® are just a few of the production techniques employed today. [ABSTRACT FROM AUTHOR]

Organic phototransistors, renowned for their exceptional biocompatibility, hold promise in phototherapy for tracking the efficacy of photosensitive drugs within treatment areas. Nevertheless, it has been found that organic semiconductors are less effective in detecting ultraviolet (UV) light because of their narrow bandgap. Here, we show that UV photodetection in phototransistors using donor-acceptor (D-A) polymer semiconductors can be significantly enhanced by incorporating PCBM nanocrystals. This integration results in a band mismatch between the nanocrystals and the D-A polymer at the interface. These nanocrystals also demonstrate a notable capability of modulating threshold voltage under UV light. The devices incorporating nanocrystals exhibit a photoresponsivity of 0.16 A/W, surpassing the photoresponsivity of the devices without nanocrystals by 50%. The specific detection rate of devices with nanocrystals is around 2.00 × 1010 Jones, which is twice as high as that of devices without nanocrystals. The presented findings offer a potential avenue to improve the efficiency of polymer phototransistors for UV detection. [ABSTRACT FROM AUTHOR]

Increased awareness of environmental pollution has changed focus to the use of biodegradable materials because they lack persistence in the environment. This article focused on the production of cellulose nanocrystals from Zhombwe, Neorautanenia brachypus (Harms) CA Sm. bagasse using steam explosion, alkaline treatment, bleaching, purification, and acid hydrolysis. The chemical composition after the treatments was determined using TAPPI standards. Further characterization was done using x‐ray Diffraction (XRD), differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA). The nanoscale dimensions and morphology of the extracted nanocrystals was determined through field emission scanning electron microscopy (FE‐SEM). FTIR spectroscopy and DSC confirmed the removal of noncellulosic compounds. XRD revealed that N. brachypus bagasse contained cellulose type I, which partly endured morphological change to polymorph II after purification and hydrolysis. FE‐SEM revealed elliptical to rod‐shaped structures after acid hydrolysis, which had a mean length and width of 1103 nm and 597 nm respectively. TAPPI tests revealed that successive chemical treatments increased crystallinity by 29.7%, enriched cellulose content by 74.2%, reduced lignin content by 21.7%, and reduced hemicellulose to less than 1%. The semicrystalline nature of the material produced in our work is a promising candidate for swelling hydrogel applications in areas such as wound dressing, heavy metal removal, controlled drug delivery, agriculture, and sanitary products. Future studies may focus on surface modification of nanocrystals to improve their thermal stability and therefore expand their range for potential industrial applications. [ABSTRACT FROM AUTHOR]

Alloying and solid‐solution formation is a powerful technique that enhances and adds properties through elemental mixing, but unfortunately, some elements simply cannot mix as their chemical nature prevents a thermodynamically stable structure. For example, the inherent nobility of platinum group metals does not favor bond formation and precludes their incorporation into higher (boron‐rich) metal borides. However, we demonstrate that when using five or more constituents, the higher mixing entropy will overcome these chemical limitations and form a stable high‐entropy alloy, demonstrating the formation of new compounds with substituents that are seemingly impossible with a traditional metal alloying approach. The high‐entropy boride (HEB) Al0.2Nb0.2Pt0.2Ta0.2Ti0.2B2 was synthesized, where platinum was forced to occupy a 12‐coordinate site, sandwiched between honeycomb borophene sheets. In addition to the unusual coordination, the boron serves as a poison panacea. Pure platinum is strongly susceptible to sulfur poisoning by adsorption, rendering a platinum catalyst ineffective. Boron is known to be resistant to sulfur poisoning. The boron sheets present in the HEB shield the platinum from sulfur while maintaining high catalytic activity. This is confirmed with the facile hydrogenation of thiol‐containing nitro compounds, where the HEB resists sulfur poisoning while retaining its high catalytic activity. [ABSTRACT FROM AUTHOR]

In this study, we report the results of continuous rotation electron diffraction studies of single DyPO4·nH2O (rhabdophane) nanocrystals. The diffraction patterns can be fit to a trigonal lattice (P3121) with lattice parameters a = 7.019 (5) and c = 6.417 (5) Å. However, there is also a set of diffuse background scattering features present that are associated with a disordered superstructure that is double these lattice parameters and fits with an arrangement of water molecules present in the structure pore. Pair distribution function (PDF) maps based on the diffuse background allowed the extent of the water correlation to be estimated, with 2–3 nm correlation along the c axis and ∼5 nm along the a/b axis. [ABSTRACT FROM AUTHOR]

Luminescent solar concentrators (LSCs) are complementary sunlight collectors for photovoltaics (PVs). Emissive fluorophores embedded in a transparent waveguide collect solar radiation over a large area and convert it into luminescence directed to the PV cells that frame the waveguide's edges. Among various fluorophores, perovskite nanocrystals (PNCs) show considerable potential for LSCs thanks to their wide size/composition/shape tunable broad absorption spectrum ranging from UV to near‐infrared, which significantly overlaps with the solar spectrum. They also feature high brightness with a photoluminescence quantum yield of up to 100% and ease of fabrication through wet chemistry approaches. In addition, PNCs can be engineered to minimize the absorption/emission overlap, which is the key to suppressing energy losses caused by reabsorption. Here, the structure and properties of PNCs and then correlate them with LSC performance is presented. The synthesis of PNCs using wet‐chemistry approaches and summarize the latest developments of PNCs‐based LSCs, categorized by the engineering strategies of PNCs and the design of the LSC configurations is critically reviewed. Finally, it is described major challenges and perspectives for future work, outlining the rational design, synthesis, PNC loading, surface engineering, and machine‐learning‐based tuning of PNC‐LSC. [ABSTRACT FROM AUTHOR]

A facile, efficient, and high yield method for producing chitin nanocrystals (ChNCs) using ultrasound-assisted phosphoric acid (PA) hydrolysis was developed. The hydrolysis was conducted at high chitin loading of 40 wt% and at a mild temperature of 50 °C, with the chitin-PA mixture remaining in a solid paste-like form throughout the reaction. The ChNCs produced showed an average length of ~ 200 nm and a cross-section of ~ 20 nm. Three reaction conditions were compared, at PA concentrations of 65, 75, and 85 wt%. Negligible changes in the sizes of ChNCs and degree of acetylation (DA) of the chitin (~ 96%) were observed, while the ChNC yield varied from 75.1 wt% at 65 wt% PA concentration to 49.6 wt% at 85 wt% PA concentration. The ChNCs were weakly charged, with a ζ-potential of ~ + 27 mV, owing to the inherent deacetylated N-acetyl groups. Overall, ultrasound-assisted PA processing provides an efficient and relatively environmentally-benign method for ChNC production. [ABSTRACT FROM AUTHOR]

Energy funneling is a phenomenon that has been exploited in optoelectronic devices based on low-dimensional materials to improve their performance. Here, we introduce a new class of two-dimensional semiconductor, characterized by multiple regions of varying thickness in a single confined nanostructure with homogeneous composition. This "noninteger 2D semiconductor" was prepared via the structural transformation of two-octahedron-layer-thick (n = 2) 2D cesium lead bromide perovskite nanosheets; it consisted of a central n = 2 region surrounded by edge-lying n = 3 regions, as imaged by electron microscopy. Thicker noninteger 2D CsPbBr3 nanostructures were obtained as well. These noninteger 2D perovskites formed a laterally coupled quantum well band alignment with virtually no strain at the interface and no dielectric barrier, across which unprecedented intramaterial funneling of the photoexcitation energy was observed from the thin to the thick regions using time-resolved absorption and photoluminescence spectroscopy.

[Display omitted] • Quaternary Ag 2 SbBiSe 4 NCs are synthesized by a colloidal synthesis route. • Ag 2 SbBiSe 4 has a cubic crystal structure and a wide band gap. • Ag 2 SbBiSe 4 maintains low lattice thermal conductivity of ca. 0.34 W m−1K−1. • Modulation doping through Sn NCs is used to tune the TE performance of Ag 2 SbBiSe 4. • A maximum ZT value of 0.64 at 760 K and a high Vickers Hardness of ~185 Hv are obtained. Materials with low intrinsic thermal conductivity are essential for the development of high-performance thermoelectric devices. At the same time, the solution processing of these materials may enable the cost-effective production of the devices. Herein, we detail a high-yield and scalable colloidal synthesis route to produce Ag 2 SbBiSe 4 nanocrystals (NCs) using amine-thiol-Se chemistry. The quaternary chalcogenide material is consolidated by a rapid hot-press maintaining the cubic crystalline structure. Transport measurements confirm that n -type Ag 2 SbBiSe 4 exhibits an inherently ultralow lattice thermal conductivity of ca. 0.34 W m−1K−1 at 760 K. Moreover, a modulation doping strategy based on the blending of semiconductor Ag 2 SbBiSe 4 and metallic Sn NCs is demonstrated to control the charge carrier concentration in the final composite material. The introduction of Sn nanodomains additionally blocks phonon propagation thus contributing to reducing the thermal conductivity of the final material. Ultimately, a peak thermoelectric figure of merit value of 0.64 at 760 K is achieved for n -type Ag 2 SbBiSe 4 -Sn nanocomposites that also demonstrate a notable Vickers hardness of 185 HV. [ABSTRACT FROM AUTHOR]

In this work, we developed an optimized ultrasonic spray pyrolysis device for obtaining metal oxide films. The key benefit of this facility lies in its cost-effectiveness and its ability to consistently coat extensive surfaces without sacrificing the integrity of the semi-conductive films, thus streamlining the manufacturing process of semiconductor films. The resulting films exhibit the following attributes: the thickness of the deposited layer is approximately 400 nm, while the diameters of ZnO1-xSx nanocrystals range from 50 to 200 nm, oriented perpendicular to the crystallographic orientation (111). In the production of nanorods, the average height is estimated to be approximately 30-50 nm, with a density of 2.9×10¹¹ cm⁻² being indicated.

In this study, the results of the investigation of the influence of Al atoms on the structural characteristics of ZnO films obtained by the sol-gel method are presented. It has been determined that the glass substrates consist of subcrystallites with dimensions of 28.6 nm, having cubic unit cells with lattice parameters a = 0.3336 nm, and their surfaces belong to the crystallographic orientation (111). It has been identified that the grown thin ZnO films consist of subcrystallites with dimensions of 39.5 nm, having a wurtzite structure with lattice parameters a = b = 0.3265 nm and c = 0.5212 nm, respectively. It has been determined that at the boundaries of the division of these subcrystallites, polycrystalline regions with sizes of 12.6 nm, 28.3 nm, 30 nm, and 33 nm are formed. Additionally, nanocrystallites with sizes of 56.8 nm self-assemble on the surface areas of the deposited films. The increase in the values of the “c”axis of the hexagonal crystal lattice of ZnO films by 0.0009 nm when doping Al atoms from 1% to 5% is explained by the shift of the main structural line (002) at small angles (Δθ=0.12°). It has been established that nanocrystallites with lattice parameters аn = 0.5791 nm, belonging to the spatial group Fd3m, self-assemble on the surface areas of ZnO:Al films. the curve due to the presence of a monoenergetic level of fast surface states at the heterojunction.

As the population increases and manufacturing grows, greenhouse gas and other harmful emissions increase. Contaminated with chemicals such as dyes, pesticides, pharmaceuticals, oil, heavy metals or radionuclides, wastewater purification has become an urgent issue. Various technologies exist that can remove these contaminants from wastewater sources, but they often demand high energy and/or high cost, and in some cases produce contaminant laden sludge that requires safe disposal. The need for methods which are less capital intensive, less operationally costly and more environmentally friendly is suggested. Cellulose-based materials have emerged as promising candidates for wastewater treatment due to their renewability, low cost, biodegradability, hydrophilicity, and antimicrobial property. In this review article, we focussed on developing sustainable and biodegradable cellulose-based materials for wastewater treatment. This article deals with cellulose-based materials’ scope and their conversion into valuable products like hydrogel, aerogel, cellulose composites, and nanocellulose. The cellulose-based materials have no harmful environmental impact and are plentiful. The modified cellulose-based materials applying as membrane, adsorbent, sorbent, and beads to purify the wastewater were discussed. Finally, the challenges and future prospects of cellulose-based materials for wastewater treatment were considered, emphasizing their potential to be sustainable and eco-friendly alternatives to traditional materials used in wastewater treatment.

Efficient hydrogen production relies on cost-effective and durable non-noble metal electrocatalysts for the hydrogen evolution reaction (HER). In this work, a liquid metal-assisted solid-flame combustion synthesis (SF-CS) method was used to create transition metal carbide TMC) nanocrystals with exposed facets. The TMCs include TiC, VC, NbC, TaC, Ta 2 C, WC, and Mo 2 C. In acidic solutions, the TMC nanocrystals show enhanced conductivity and superior HER performance, as evidenced by their lower Tafel slope, higher current density, and decreased overpotential. In particular, Mo 2 C nanocrystals exhibit an overpotential of 95 mV and a Tafel slope of 26 mV dec−1. These findings highlight a noteworthy improvement over previously reported nanostructures in recent years in terms of the HER properties of Mo 2 C with particular facets. This improvement is attributed to the unique surface characteristics, such as energy and active sites, which are impacted by various factors and require more investigation to meet the intended goals. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Highly stable perovskite nanocrystals in water were obtained by modifing wool keratin (WK) and crosslinking agent (PAPI). • CPB/WK-PAPI nanocrystals show excellent photoluminescence retention over time even after 512 days (>40 %). • Portable, low cost, and visualize test strips for amines were successfully made from these nanocrystals. Perovskite nanocrystals (PNCs) have emerged as promising candidates for fluorescent probes owing to their outstanding photoelectric properties. However, the conventional CsPbBr 3 (CPB) NCs are extremely unstable in water, which has seriously limited their sensing applications in water environment. Herein, we present a powerful ligand engineering strategy for fabricating highly water-stable CPB NCs by using a biopolymer of wool keratin (WK) as the passivator and the polyaryl polymethylene isocyanate (PAPI) as the cross-linking agent. In particular, WK with multi-functional groups can serve as a polydentate ligand to firmly passivate CPB NCs by the ligand exchange process in hot toluene; and then the addition of PAPI can further encapsulate CPB NCs by the crosslinking reaction between PAPI and WK. Consequently, the as-prepared CPB/WK-PAPI NCs can maintain ∼ 80 % of their relative photoluminescence (PL) intensity after 60 days in water, and they still maintain ∼ 40 % of their relative PL intensity even after 512 days in the same environment, which is one of the best water stabilities compared previously reported polymer passivation methods. As a proof-of their application, the portable CPB/WK-PAPI NCs-based test strips are further developed as a fluorescent nanoprobe for real-time and visual monitoring amines and food freshness. Among various amine analytes, the as-prepared test strips exhibit higher sensitivity towards conjugated amines, achieving a remarkable detection limit of 18.3 nM for pyrrole. Our research not only introduces an innovative strategy involving natural biopolymers to enhance the water stability of PNCs, but also highlights the promising potential of PNCs for visually and portably detecting amines and assessing food freshness. [ABSTRACT FROM AUTHOR]

In this paper, high transmittance glass-ceramics containing Zirconium Yttrium Oxide (Zr 0.82 Y 0.18 O 1.91) nanocrystals were successfully prepared by melt cooling and crystallization heat-treatment method. The effects of Y 2 O 3 concentration on the structure, crystallization performance, transmittance, and indentation fracture toughness of Na 2 O–Al 2 O 3 –B 2 O 3 –SiO 2 –ZrO 2 glass and glass-ceramics were explored. The addition of Y 2 O 3 improved the Vickers hardness (4.81 GPa–5.25 GPa) and indentation fracture toughness (0.78 MPam1/2 to 0.95 MPam1/2) of the glasses. Y 2 O 3 successfully facilitated the precipitation of the non-alkaline crystalline phase Zr 0.82 Y 0.18 O 1.91 at low heat-treatment temperatures. The precipitation of Zr 0.82 Y 0.18 O 1.91 nanocrystals improves the Vickers hardness (5.17 GPa–5.56 GPa) and indentation fracture toughness (0.90 MPam1/2 to 1.01 MPam1/2) in glass-ceramics, while concurrently preserving a high level of visible light transmittance (∼90 %). This demonstrates its potential applications in the field of protective covers for electronic displays. [ABSTRACT FROM AUTHOR]

The possibility of controlled synthesis of nanodendritic structures of high-entropy alloys (HEAs) is considered. The fundamental results on the electrical conductivity depending on the topological structure for iron-containing alloys and compounds in dendritic HEAs are discussed. Emphasis is placed on the theoretical and experimental studies of the structural features on the surfaces of HEAs with objects of fractal dimension. The influence of localized cluster inhomogeneities on the solid surface on the electrophysical parameters of samples has been determined taking into account the entropy of mixing in the surface topological structures of dendritic type. The fractal structures of dendrites are analyzed as prototypes of nanoantennas. It is shown that the main reason for the formation of the functional characteristics of such structures is the occurrence of a phase transition with the parameters of the emerging topological fractal structures (dendrites), which can serve as standard thermodynamic parameters, such as temperature and pressure. They will determine the phase states of the medium, including possible trends towards superconductivity. At the same time, the technology of obtaining such surface nanoscale topological objects, based on laser ablation, is quite simple and universal with controllable characteristics of the parameters of the resulting (emerging) structures of various configurations. [ABSTRACT FROM AUTHOR]

The self-diffusion coefficients for symmetrical tilt grain boundaries and for grain boundaries of the general type in nickel were calculated by atomistic simulation methods. The special tilt grain boundaries were simulated using a bicrystal model; and general-type grain boundaries, in a nanocrystal model. The self-diffusion coefficient was represented as a temperature dependence. The activation energies of self-diffusion were determined. [ABSTRACT FROM AUTHOR]

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NaA zeolite (Si/Al = 1.00) has been commercially applied for capturing radioactive 90Sr2+ because of its high surface charge density, effectively stabilizing the multivalent cation. However, owing to its narrow micropore opening (4.0 Å), large micron-sized crystallites, and bulkiness of hydrated Sr2+, the Sr2+ exchange over NaA has been limited by very slow kinetics. In this study, we synthesized nanocrystalline low-silica X by minimizing a water content in a synthesis gel and utilizing a methyl cellulose hydrogel as a crystal growth inhibitor. The resulting zeolite exhibited high crystallinity and Al-rich framework (Si/Al of approximately 1.00) with the sole presence of tetrahedral Al sites, which are capable of high Sr2+ uptake and ion selectivity. Meanwhile, the zeolite with a FAU topology has a much larger micropore opening size (7.4 Å) and a much smaller crystallite size (∼340 nm) than NaA, which enable significantly enhanced ionexchange kinetics. Compared to conventional NaA, the nanocrystalline low-silica X exhibited remarkably increased Sr2+-exchange kinetics (> 18-fold larger rate constant) in batch experiments. Although both the nanocrystalline low-silica X and NaA exhibited comparable Sr2+ capacities under equilibrated conditions, the former demonstrated a 5.5-fold larger breakthrough volume than NaA under dynamic conditions, attributed to its significantly faster Sr2+-exchange kinetics. [ABSTRACT FROM AUTHOR]

Despite the various therapeutic benefits and high tolerance of orally administered silybin, poor water-solubility can be the main restrictive physicochemical feature, which results in low oral bioavailability in the absorption. A milk thistle nanocrystal formulation (HM40) was prepared using a modified wet-milling method. Comprehensive characterization was performed to determine the physical morphology, crystallinity, and physicochemical properties. The long-term stability was evaluated over 24 months. In vitro silybin release was assessed at pH 1.2 for 2 h, followed by pH 6.8 for 4 h. Finally, in vivo pharmacokinetic studies were conducted in rats and healthy human volunteers. HM40 exhibited a nanocrystal structure maintaining crystallinity and enhanced the solubility and dissolution of silybin compared to that of the raw material. The stability over 24 months revealed consistent surface morphology, particle size, silybin content, and solubility. In vitro release profiles indicated a significant increase in the silybin release from HM40. In vivo pharmacokinetic studies demonstrated that HM40 showed 2.61- and 1.51-fold higher oral bioavailability in rats and humans, respectively, than that of the reference capsule. HM40 formulation presents a stable and promising approach for the oral delivery of poorly water-soluble silybin, with the potential for use in pharmaceutical formulations containing milk thistle. [ABSTRACT FROM AUTHOR]

As the population increases and manufacturing grows, greenhouse gas and other harmful emissions increase. Contaminated with chemicals such as dyes, pesticides, pharmaceuticals, oil, heavy metals or radionuclides, wastewater purification has become an urgent issue. Various technologies exist that can remove these contaminants from wastewater sources, but they often demand high energy and/or high cost, and in some cases produce contaminant laden sludge that requires safe disposal. The need for methods which are less capital intensive, less operationally costly and more environmentally friendly is suggested. Cellulose-based materials have emerged as promising candidates for wastewater treatment due to their renewability, low cost, biodegradability, hydrophilicity, and antimicrobial property. In this review article, we focussed on developing sustainable and biodegradable cellulose-based materials for wastewater treatment. This article deals with cellulose-based materials' scope and their conversion into valuable products like hydrogel, aerogel, cellulose composites, and nanocellulose. The cellulose-based materials have no harmful environmental impact and are plentiful. The modified cellulose-based materials applying as membrane, adsorbent, sorbent, and beads to purify the wastewater were discussed. Finally, the challenges and future prospects of cellulose-based materials for wastewater treatment were considered, emphasizing their potential to be sustainable and eco-friendly alternatives to traditional materials used in wastewater treatment. [ABSTRACT FROM AUTHOR]

In this paper, synthetically scaled-up degenerately n-type doped indium tin oxide (Sn:In2O3) nanocrystals are described as highly transparent conductive materials possessing both optoelectronic and crystalline properties. With tin dopants serving as n-type semiconductor materials, they can generate free-electron carriers. These free electrons, vibrating in resonance with infrared radiation, induce strong localized surface plasmon resonance (LSPR), resulting in efficient infrared absorption. To commercialize products featuring Sn:In2O3 with localized surface plasmon resonance, a scaled-up synthetic process is essential. To reduce the cost of raw materials during synthesis, we aim to proceed with synthesis in a large reactor using industrial raw materials. Sn:In2O3 can be formulated into ink dispersed in solvents. Infrared-absorbing ink formulations can capitalize on their infrared absorption properties to render opaque in the infrared spectrum while remaining transparent in the visible light spectrum. The ink can serve as a security ink material visible only through infrared cameras and as a paint absorbing infrared light. We verified the transparency and infrared absorption properties of the ink produced in this study, demonstrating consistent characteristics in scaled-up synthesis. Due to potential applications requiring infrared absorption properties, it holds significant promise as a robust platform material in various fields. [ABSTRACT FROM AUTHOR]

In this work, we developed an optimized ultrasonic spray pyrolysis device for obtaining metal oxide films. The key benefit of this facility lies in its cost-effectiveness and its ability to consistently coat extensive surfaces without sacrificing the integrity of the semiconductive films, thus streamlining the manufacturing process of semiconductor films. The resulting films exhibit the following attributes: the thickness of the deposited layer is approximately 400 nm, while the diameters of ZnO1-xSx nanocrystals range from 50 to 200 nm, oriented perpendicular to the crystallographic orientation (111). In the production of nanorods, the average height is estimated to be approximately 30-50 nm, with a density of 2.9×1011 cm-2 being indicated. [ABSTRACT FROM AUTHOR]

In this study, the results of the investigation of the influence of Al atoms on the structural characteristics of ZnO films obtained by the sol- gel method are presented. It has been determined that the glass substrates consist of subcrystallites with dimensions of 28.6 nm, having cubic unit cells with lattice parameters a = 0.3336 nm, and their surfaces belong to the crystallographic orientation (111). It has been identified that the grown thin ZnO films consist of subcrystallites with dimensions of 39.5 nm, having a wurtzite structure with lattice parameters a = b = 0.3265 nm and c = 0.5212 nm, respectively. It has been determined that at the boundaries of the division of these subcrystallites, polycrystalline regions with sizes of 12.6 nm, 28.3 nm, 30 nm, and 33 nm are formed. Additionally, nanocrystallites with sizes of 56.8 nm self-assemble on the surface areas of the deposited films. The increase in the values of the "c"axis of the hexagonal crystal lattice of ZnO films by 0.0009 nm when doping Al atoms from 1% to 5% is explained by the shift of the main structural line (002) at small angles (40-0.12°). It has been established that nanocrystallites with lattice parameters an = 0.5791 nm, belonging to the spatial group Fd3m, self-assemble on the surface areas of ZnO:Al films. the curve due to the presence of a monoenergetic level of fast surface states at the heterojunction. [ABSTRACT FROM AUTHOR]

Developing hierarchical and nanoscale ZSM-5 catalysts for diffusion-limited reactions has received ever-increasing attention. Here, ZSM-5 architecture integrated with hierarchical pores and nanoscale crystals was successfully prepared via in situ self-assembly of nanoparticles-coated silicalite-1. First, the oriented attachment of amorphous nanoparticles on external surface of silicalite-1 was achieved by controlling the alkalinity of Si-Al coating solution. The partial exposure of the external surface of silicalite-1 ensured the uniform removal of silicon in the bulk phase for the creation of hierarchical pores during the subsequent desilication-recrystallization. The uniform removal of silicon species in the bulk phase was mainly due to the synergistic effect of surface protection and alkaline etching, which could be balanced by regulating the relative amount of tetrapropylammonium cation and OH− in desilication-recrystallization solution. Importantly, the removed silicon from silicalite-1 recrystallized and in situ assembled into final ZSM-5 nanocrystals induced by surface Si-Al nanoparticles. The hierarchical pores and nanoscale crystals on this integrated architecture not only promoted the removal of coke precursors from micropores but also provided large external specific surface (91 m2·g−1) for coke deposition. Consequently, a much longer catalytic lifetime was achieved for methanol-to-aromatics reaction compared to conventional hollow structure ZSM-5 (84 h vs 46 h), with relatively high stability. [ABSTRACT FROM AUTHOR]

The innovative work shows a new strategy to modify the physicochemical properties of medicines and improve patients' lives. The mechanochemical synthesis and characterization of the first Norfloxacin nanocrystal are described. In recent decades, nanotechnology has gained significant attention in the scientific field through the study of the design, formation and application of materials at the nanoscale level. In the pharmaceutical sector, nanotechnology has been the focus of studies on systems that allow increased bioavailability. The present work investigated the formation of pharmaceutical nanocrystals. Nanocrystals are crystalline nanoparticles ranging in size from a few nanometers to 1,000 nm, composed of 100% of the drug and stabilized by surfactants or polymeric stabilizers. They have a safe formulation and are well tolerated compared to conventional medicines. The drug used in this study was Norfloxacin, a broad-spectrum antibiotic that has low bioavailability. Several nanocrystallization techniques are found in the literature, among which the mechanochemical method stands out. Mechanochemistry is an approach that allows the reduction of particle size through the mechanical energy provided in the reaction medium. Thus, it was possible to obtain nanomaterials and explore the influence of surfactants in controlling the particle size and morphology of the materials obtained.

Abstract This study examined the impact of acid hydrolysis, tempo oxidation, and mechanical grinding on the physical, thermal, and structural properties of α-chitin nanocrystals and nanofibers. The manufacturing methods could influence the diameter, functional groups, and crystal patterns of the resulting nanoparticles. Analysis of the DLS results revealed that the size of acidic nanocrystals were smaller and showed improved dispersibility. The XRD patterns indicated that the chemical and mechanical treatments did not alter the crystalline arrangement of the α-chitin. FT-IR spectra analysis revealed that the chemical and mechanical methods did not affect the functional groups of the nanoparticles. DSC results showed that the nanoparticles had good thermal stability up to 400 °C, and it was found that the nanofibers had better thermal resistance due to their longer length. In the FE-SEM images, the nanoparticles were observed as fiber mats with a length of more than 100 nm. It was also found that the diameter of the nanoparticles was less than 100 nm.

The conditions and parameters for the synthesis of metal oxide films (ZnO, SnO2, and Zn2SnO4) by spray pyrolysis have been determined. The films were synthesized from aqueous solutions; the main differences between the methods were in the composition of the precursors, in the modes and time of deposition. The crystal structure of the Zn2SnO4 film corresponds to the cubic lattice, which belongs to the space group Fd3m with blocks 53 nm in size and lattice parameters a = 6.238 Å. Films of SnO2 and ZnO nanocrystallites 28 and 31 nm in size coherently arranged with lattices in the volume of thin Zn2SnO4 films can exhibit quantum size effects, which is of interest for modern nanotechnology. The crystals of the obtained SnO2 films have a tetragonal Bravais lattice with the space group P4 2/mnm with lattice parameters a = b = 4.836 Å and c = 3.245 Å, and the size of the SnO2 film subcrystals is 61 nm. The resulting ZnO films belong to the C6/mmc space group and the crystal lattice has a hexagonal syngony with the wurtzite structure with parameters a = b = 0.3265 nm and c = 0.5212 nm. It has been determined that, on the surface of the thin film grown, zinc oxide bumps with sizes LZnO ≈ 84 nm appear, which affect the unique properties of the samples. It is shown that the resulting thin Zn2SnO4, SnO2, and ZnO films can be used in a wide range of applications from sensitive sensor elements to coatings in transparent electronics in terms of their optical parameters.

The growth, yield, and quality of cauliflower (Brassica oleracea var. botrytis L.) cv. Pusa Snowball K-1 were studied using Fe2O3-nano fertilizer (Fe2O3-N) in combination with Azotobacter, Farmyard manure (FYM), and Phosphorus solubilizing bacteria (PSB). Hydrothermally synthesized Fe2O3 nanoparticles characterized with XRD, FTIR, and SEM. The experiment consisting 12 treatments viz. T1 (Fe2O3-N), T2 comprising of Fe2O3-N + FYM + Azotobacter + PSB, T3 (Fe2O3-N + Azotobacter + PSB), T4 (Fe2O3-N + FYM + Azotobacter), T5 (Fe2O3-N + FYM + PSB), T6 (Fe2O3-N + FYM), T7 (Fe2O3-N + Azotobacter), T8 (Fe2O3-N + PSB), T9 (PSB), T10 (Azotobacter), T11 (FYM), and T12 (control). Fe2O3 NPs positively enhance the photosynthetic activity and stimulate catalyze enzymatic action in plant leaves that effect the health of the plant and remarkably increase the crop yield. Application of Fe2O3-nano fertilizer (Fe2O3-N) along the Azotobacter, FYM, and PSB was shown encouraging growth effects to improve the cropping behavior. Fe2O3 NPs positively enhance the photosynthetic activity and stimulate catalyze enzymatic action in plant leaves that effect the health of the plant and remarkably increase the crop yield. This research is a detailed study of nontoxic Fe2O3 nanoparticle as nanofertilizers on the cauliflower (Brassica oleracea var. Botrytis L.) cv. Pusa Snowball K-1. Growth of nanoparticles was carried out by environment friendly hydrothermal method. It was found that Fe2O3 NPs positively enhance the photosynthetic activity and stimulate catalyze enzymatic action in plant leaves that effect the health of the plant and remarkably increase the crop yield. The novelty of this work is that nanoparticles are used to enhance the growth and yield of the crop. This research will reflect new point of view toward the nanoparticle as nanofertilizers instead of indiscriminate use of chemical fertilizers and pesticides to increase the yield of crop. [ABSTRACT FROM AUTHOR]

This study investigates the extraction and isolation of cellulose nanocrystals (CNCs) from grape pomace, an agricultural waste material abundant in phenolic compounds. The process involves organic isolation, alkaline bleaching at various concentrations, and acid hydrolysis to obtain pure cellulose and CNCs. Structural analyses using XRD, FTIR, and TGA reveal critical insights. Comparison with existing research on CNCs derived from other biomass sources, such as Siam weed, highlights similarities in the preparation method and structural confirmation through FTIR analysis. TGA results demonstrate the higher initial decomposition temperature of cellulose from grape pomace compared to unprocessed pomace, showcasing improved thermal stability after chemical purification. In TGA analysis because of high crystal content, 3% NaOH/H2O2 alkaline isolation exhibits the lowest water weight loss among all samples. Observations on crystallinity index variations in CNCs attribute these changes to alterations in alkali isolation concentration, corroborated by previous studies. The success of organic and alkaline isolations underscores the effectiveness of these methods in obtaining cellulose from grape pomace. The obtained cellulose and CNCs exhibit high potential in biomaterial applications. This study elevates the value of grape pomace from a disregarded waste product to a valuable source of cellulose for diverse applications in biomaterials, food, and bioprocess. Furthermore, the exploration of CNCs from grape pomace in natural packaging coatings and drug carrier systems opens new avenues for their utilization. In conclusion, the study emphasizes the overlooked potential of grape pomace and establishes the significance of cellulose extracted from this source, suggesting a promising future in various industries. [ABSTRACT FROM AUTHOR]

Plant fibers have been studied as sources of nanocellulose due to their sustainable features. This study investigated the effects of acid hydrolysis parameters, reaction temperature, and acid concentration on nanocellulose yield from maguey (Agave cantala) fiber. Nanocellulose was produced from the fibers via the removal of non-cellulosic components through alkali treatment and bleaching, followed by strong acid hydrolysis for 45 min using sulfuric acid (H2SO4). The temperature during acid hydrolysis was 30, 40, 50, and 60 °C, and the H2SO4 concentration was 40, 50, and 60 wt. % H2SO4. Results showed that 53.56% of raw maguey fibers were isolated as cellulose, that is, 89.45% was α-cellulose. The highest nanocellulose yield of 81.58 ± 0.36% was achieved from acid hydrolysis at 50 °C using 50 wt. % H2SO4, producing nanocellulose measuring 8–75 nm in diameter and 72–866 nm in length, as confirmed via field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) analysis. Fourier-transform infrared spectroscopy (FTIR) analysis indicated the chemical transformation of fibers throughout the nanocellulose production process. The zeta potential analysis showed that the nanocellulose had excellent colloidal stability with a highly negative surface charge of −37.3 mV. Meanwhile, X-ray diffraction (XRD) analysis validated the crystallinity of nanocellulose with a crystallinity index of 74.80%. Lastly, thermogravimetric analysis (TGA) demonstrated that the inflection point attributed to the cellulose degradation of the produced nanocellulose is 311.41 °C. [ABSTRACT FROM AUTHOR]

After 3 h of irradiation, the H 2 O 2 accumulation of BiPO 4 nanocrystals (BIP NCs) reaches 30.44 mM·g−1, which is 3.13 times higher compared to bulk BiPO 4 (BIP-B) synthesized through hydrothermal synthesis. This significant increase can be attributed to the nanocrystal structure, which shortens charge migration distance. Consequently, the path of H 2 O 2 production is altered from a two-step one-electron pathway to a more efficient one-step two-electron pathway. [Display omitted] The photocatalytic production of H 2 O 2 has gained recognition as an economical and eco-friendly technology, but it suffers from limitations such as low production rates and difficulty in achieving high concentrations. This study was designed to overcome these limitations by preparing BiPO 4 nanocrystals (BIP NCs) via high-temperature hydrolysis, and X-ray diffraction (XRD) and transmission electron microscopy (TEM) indicated that BIP NCs with particle sizes of 8.5 ± 3 nm were synthesized. In a photocatalytic performance test, only H 2 O and O 2 were used to produce H 2 O 2 , resulting in an accumulation of H 2 O 2 of up to 30.44 mM·g−1, as measured with the potassium titanium oxalate method; this value was 3.13 times greater than that of bulk BiPO 4 (BIP-B). The resulting nanocrystals demonstrated superior electron-hole transport and separation efficiency compared to those of BIP-B, and H 2 O 2 was formed in a one-step two-electron process. Furthermore, a film composed of a gas diffusion layer (GDL) and BIP NCs provided continuous accumulation of H 2 O 2 ; a concentration of 7.23 mM was achieved after 96 h of reaction, and the stability of the film was confirmed by comparing scanning electron microscopy (SEM) images obtained before and after the reaction. Construction of a nanocrystalline structure to enhance the activities of photocatalysts and films and achieve continuous accumulation of H 2 O 2 will provide insights into the photocatalytic production of highly concentrated H 2 O 2. [ABSTRACT FROM AUTHOR]

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The crystal growth of hydroxyapatite (HAp) using a solvothermal method was investigated under various reaction conditions. The purpose of the present study is the synthesis of HAp nanocrystals with multiple facets and the atomic arrangement for various orientations of the crystal was clarified. HAp nanorods were obtained at 200°C after 24 h using a reaction medium of water. The atomic arrangement in HAp nanorods was examined for a characteristic facet in the direction of [21−13−] and [0110−] incidences and crystal orientation along the c‐axis of HAp nanorod was confirmed using electron microscopy. The present study clarifies the HAp crystal growth mechanism, where the adsorption of cations or anions onto the crystal facet determines the HAp crystal shape. The crystals of HAp grew along the c‐axis and became rod‐shaped suggesting that cations were adsorbed predominantly over anions. [ABSTRACT FROM AUTHOR]

The conditions and parameters for the synthesis of metal oxide films (ZnO, SnO2, and Zn2SnO4) by spray pyrolysis have been determined. The films were synthesized from aqueous solutions; the main differences between the methods were in the composition of the precursors, in the modes and time of deposition. The crystal structure of the Zn2SnO4 film corresponds to the cubic lattice, which belongs to the space group Fd3m with blocks 53 nm in size and lattice parameters a = 6.238 Å. Films of SnO2 and ZnO nanocrystallites 28 and 31 nm in size coherently arranged with lattices in the volume of thin Zn2SnO4 films can exhibit quantum size effects, which is of interest for modern nanotechnology. The crystals of the obtained SnO2 films have a tetragonal Bravais lattice with the space group P4 2/mnm with lattice parameters a = b = 4.836 Å and c = 3.245 Å, and the size of the SnO2 film subcrystals is 61 nm. The resulting ZnO films belong to the C6/mmc space group and the crystal lattice has a hexagonal syngony with the wurtzite structure with parameters a = b = 0.3265 nm and c = 0.5212 nm. It has been determined that, on the surface of the thin film grown, zinc oxide bumps with sizes LZnO ≈ 84 nm appear, which affect the unique properties of the samples. It is shown that the resulting thin Zn2SnO4, SnO2, and ZnO films can be used in a wide range of applications from sensitive sensor elements to coatings in transparent electronics in terms of their optical parameters. [ABSTRACT FROM AUTHOR]

The results of theoretical calculations of electronic states of the gallium oxide (Ga2O3) nanocrystals both doped with donor impurity and undoped have been presented in the paper. In the envelope function approximation, the structure, states and energy levels of size quantization in the nanocrystals were determined. According to our calculations, the electron-hole pair forms a bound state of the exciton type in the nanocrystal. The typical donor impurities in Ga2O3, such as silicon and tin, were shown to create bandgap states localized in a spatial domain being several times smaller than the nanocrystal’s volume. Forming a compact neutral pair, the electron and donor ions have no noticeable influence on the states of the optically excited electron-hole pairs. The effect of impurity implantation on recombination processes was also discussed.

In this work, we prepared sulfur-zinc nanoparticles (ZnS-TGA) functionalized with thioglycolic acid by a hydrothermal method and tested their photodegradation ability by solar irradiation. ZnS-TGA were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), high-resolution transmission electron microscope (HR-TEM), UV–Vis spectrophotometer and photoluminescence spectroscopy. In the characterization of these nanoparticles, thioglycolic acid proved to be a strong capping ligand, with a specific surface area of 36.82 m2/g and an average size of 7.15 nm. To test the photocatalytic degradability of the product, methylene blue (MB) was used as a model pollutant. Various operational variables were investigated, including pH, amount of nanoparticles, dye concentration, contact time and temperature. The equilibrium adsorption tests, and the statistical physical calculations allowed the analysis of the energetic and steric variables of the adsorption of MB dye molecules on the surface of these nanoparticles. The equilibrium data were well fitted with Langmuir-Freundlich (L-F) and the adsorption kinetics with pseudo-first order. The maximum adsorption capacity of the MB dye removal process was 30.92 mg g−1 at pH 7 and 298 K, and this process was spontaneous and exothermic. The dye molecules and the surface of the nanoparticles exhibited physical interactions with adsorption energies of 23.31–25.92 kJ/mol. The photocatalytic activity of these nanoparticles resulted in a dye degradation efficiency of 91.1 % in 180 min. The photocatalytic efficiency remained almost unchanged after five consecutive degradation cycles, resulting in a methylene blue degradation of 85 %. According to these results, these environmentally friendly nanoparticles have the potential to purify industrial and urban liquids contaminated with harmful organic compounds such as dye molecules.

Background and purpose: In our previous studies, drug nanocrystals were directly prepared by solution crystallization, possessing uniform particle size and morphology suitable for intravenous (IV) injection. These nanocrystals accumulated in a small percentage of their injected dose in tumor-bearing mice but showed similar anti-tumor effectiveness and much-reduced side effects compared with current commercial solubilized and encapsulated delivery systems. Experimental approach: In this study, we aimed to delineate possible controlling factors for the pharmacokinetics (PK) and biodistribution behaviors of paclitaxel (PTX) nanocrystals tested in mice by applying physiologically based pharmacokinetics (PBPK) modeling, coupled with pharmacodynamics (PD) simulation, to the data. Key Results: Our results show that clearance of the drug plays a significant, if not the most important, role in determining tissue distribution, including tumor accumulation of PTX nanocrystals. Surface treatment of drug nanocrystals with polymeric surfactants also appeared to affect PK profiles and PD outcomes. Importantly, when scaled to model human parameters, our PK/PD simulations suggest that drug distribution in humans, as opposed to animal models, was significantly influenced by tissue partitioning rather than drug clearance. This finding could facilitate the design and development of future drug delivery systems. Conclusion: Drug nanocrystals deposited in tissues, including tumors, could therefore act as depots, releasing the drug back into the circulation, possibly contributing to extended treatment, as well as any detrimental effects.

Cosmetics have evolved beyond mere skin beautifying agents. Cosmetics are now combined with active ingredients to support skin health. This evolution underpins the emergence of dream cosmetics, where innovation is continuously pursued. Indeed, nanotechnology has responded in force to the notion of dream cosmetics. Nanocrystals are expected to overcome the barriers posed by issues, such as poor solubility of bioactive agents and skin penetration. Moreover, nanocrystals exhibit multiple features, making dream cosmetics achievable. However, the clinical translation of nanocrystals is hampered by concern of negative host responses associated with long-term use. Accordingly, screening by integrated omics is needed because because multiple omics offer comprehensive nanotoxicity evaluation by identifying new molecular pathways and toxicity markers.

[Display omitted] It was established that the particle size of titanium oxide β-Ti 3 O 5 has a great influence on the processes of phase formation and the stability of particles during heating. It was shown that at a temperature of about 456 K, β-Ti 3 O 5 micro crystals undergo a reversible first-order phase transition, in which the low- temperature β-Ti 3 O 5 phase is transformed into the high-temperature λ- Ti 3 O 5 phase, and at higher temperatures the β-Ti 3 O 5 phase is partially oxidized to form the Magnéli phase Ti 4 O 7. It was found that β-Ti 3 O 5 nanocrystals are unstable in an argon atmosphere and at temperatures above 400 K the β-Ti 3 O 5 powder is oxidized. [ABSTRACT FROM AUTHOR]

Organic phototransistors, renowned for their exceptional biocompatibility, hold promise in phototherapy for tracking the efficacy of photosensitive drugs within treatment areas. Nevertheless, it has been found that organic semiconductors are less effective in detecting ultraviolet (UV) light because of their narrow bandgap. Here, we show that UV photodetection in phototransistors using donor-acceptor (D-A) polymer semiconductors can be significantly enhanced by incorporating PCBM nanocrystals. This integration results in a band mismatch between the nanocrystals and the D-A polymer at the interface. These nanocrystals also demonstrate a notable capability of modulating threshold voltage under UV light. The devices incorporating nanocrystals exhibit a photoresponsivity of 0.16 A/W, surpassing the photoresponsivity of the devices without nanocrystals by 50%. The specific detection rate of devices with nanocrystals is around 2.00 × 1010 Jones, which is twice as high as that of devices without nanocrystals. The presented findings offer a potential avenue to improve the efficiency of polymer phototransistors for UV detection.