Ultraviolet Absorption Properties Research Articles

Tandem Acylation and Aromatization of Vinylogous Esters: A Regiospecific Approach to Resorcinyl Ketones.

This study demonstrates the direct conversion of vinylogous esters into selectively protected 6-acyl resorcinols (4-alkoxy/aryloxy-2-hydroxy arylketones) in a regiospecific manner. Resorcinyl ketones are first-time synthesized, diverging from their traditional roots, originating from non-benzenoid pool materials. Converting cyclohexenones into phenol- or resorcinol-based arylketones remains challenging due to the stability and reactivity issues of intermediate products. Addressing this critical gap, we introduce a novel strategy: sequential one-pot acylation and oxidative aromatization of vinylogous esters. This innovative approach aims to surmount the long-standing barrier, facilitating the synthesis of diverse resorcinyl ketones. Furthermore, this method proves valuable for the synthesis of functionalized diaryl ethers and in the total synthesis of bioactive natural products and drug molecules such as angolensin, isoliquiritigenin, demethylsorbicillin, ponganone VII, and ipriflavone. It is also useful for modifying bioactive acids and alcohols by introducing a resorcinol functionality in the late stage of synthesis. Synthetic analogues of oxybenzone demonstrated superior ultraviolet (UV) absorption properties, effectively covering the entire UV-A and UV-B regions, spanning from 230 to 410 nm.

Synthesis and properties of the natural ultraviolet absorber gadusol in Komagataella phaffii

Gadusol, an efficient natural ultraviolet (UV) absorbing substance with antioxidant capacity, is ubiquitous in aquatic organisms such as microorganisms, algae, and fish eggs. In order to address issues such as its low natural extraction yield and environmental unfriendliness, we introduced the gadusol synthesis pathway from zebrafish into Komagataella phaffii and successfully constructed the recombinant strain capable of synthesizing gadusol. The xylose assimilation genes derived from Scheffersomyces stipitis were further introduced into the recombinant strain to increase the content of the key substrate sedoheptulose 7-phosphate (S7P). The results showed that the utilization of xylose was an effective strategy to increase the yield of gadusol. In the medium with only xylose as the substrate, the yield of gadusol reached 141.8 mg/L (32.3 mg/g dry cell weight, DCW), which was about 46 times of that in the medium with only glucose as the substrate. The product showed obvious absorption in the range of 275-305 nm, with the maximum absorption at 290 nm. Moreover, the product demonstrated antioxidant capacity. After reaction for 5 h, the ferric ion reducing antioxidant power (FRAP), 2, 2'-azino- bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging rates changed by 90.83%, 25.50%, and 131.80%, respectively, which suggested that the product may be used as a long-acting antioxidant. This study demonstrated the great potential of K. phaffii as a chassis for the biosynthesis of natural UV absorbers. The biosynthesized gadusol has good UV absorption and antioxidant properties, which provides a theoretical basis for the industrial production and application of gadusol.

Ligand-Engineered Structural and Physiochemical Properties of 1D Molybdenum-MOFs: A Seldom Explored System for Photocatalytic Applications.

As one of the seldom explored systems, molybdenum-based metal-organic frameworks (Mo-MOFs) with different ligands such as terephthalic acid (Mo-TA), 2-aminoterephthalic acid (Mo-ATA), benzenetricarboxylic acid (Mo-BTC), 2-methylimidazole (Mo-2MI), 2-bipyridine (Mo-2bpy), and 4-bipyridine (Mo-4bpy) were developed in this study. X-ray diffraction (XRD), Raman, and attenuated total reflectance-infrared (ATR-IR) analyses confirmed the ligand-dependent crystal structure of the Mo-MOFs along with the characteristic functional groups present in the respective systems. Interestingly, the morphology of all of these the developed Mo-MOFs was found to be a one-dimensional rod-like structure, which was attributed to the binding nature of the ligands onto the growing Mo-frameworks. Optical analysis indicated that all these Mo-MOFs exhibit ultraviolet (UV) light absorption properties with band gap energy in the range of 3.47-3.03 eV. Among the various Mo-MOFs developed, Mo-4bpy MOF degraded a maximum of ∼76 and 62% of malachite green and Congo red dyes, respectively, under sunlight irradiation. The observed improved photocatalytic efficiency of Mo-4bpy MOF was attributed to its appropriate band edge potential, confirmed by Mott-Schottky analysis, improved carrier lifetime (∼34.6 ns) estimated using the time-resolved photoluminescence (TRPL) spectrum, presence of elements with stable oxidation states in the system confirmed by X-ray photoelectron spectroscopy (XPS), improved charge transfer characteristics, and decreased recombination resistance, as confirmed by impedance and PL analyses, respectively. The degradation of Mo-4bpy MOFs mediated by superoxide (•O2-) and hydroxyl radicals (OH•) was further confirmed by scavenger studies. Cyclic studies performed for up to 5 cycles suggested that the degradation efficiency of the Mo-4bpy MOF was stable, attributed to its excellent structural, optical, and morphological features confirmed via postcharacterization of the recycled photocatalyst.

Biodegradable containers made from mesquite pods Prosopis juliflora (Sw.) DC for the production of plant seedlings

Currently there is a tireless search for sustainable solutions to minimize plastic waste in the environment. In this sense, this work aimed to develop a biodegradable packaging from mesquite pods (Prosopis juliflora), to act as a potential replacement for commercial packaging in the agro-industrial sector. To this end, mesquite pod flour (FV) was obtained to produce containers for plant seedlings. During processing, the flour was mixed with an adhesive solution of wheat starch, glycerol and NPK, molded manually and dried in an oven. The containers were evaluated by X-ray Diffraction (XRD), Fourier Transform Infrared (FTIR), Ultraviolet-Visible Spectrophotometry (UV-Vis), Mechanical Resistance, Contact Angle (AC) and Water Absorption. The packages obtained semi-crystalline behavior, due to the presence of lignocellulosic compounds and the addition of NPK did not influence the chemical interactions between the adhesive solution and the FV. With the increase in the concentration of FV in the containers, the ultraviolet light absorption properties were intensified, but resulted in packages with lower tensile strength and greater water absorption.

Ginseng fruit rare saponins (GFRS), a promising anti-wrinkle agent: Evidence of its antioxidant effect and its capacity to prevent matrix metalloproteinase (MMPs) expression in vitro and in vivo

Rare saponins show numerous significant biological activities, however, there has been no research on using ginseng fruit rare saponins (GFRS) to minimize skin wrinkles. This paper studied the anti-wrinkle effect, related mechanism, material basis of efficacy, and structure-activity relationship of GFRS in vivo and in vitro. The findings demonstrate that GFRS has potent collagenase and elastase inhibition capabilities in addition to superior ultraviolet absorption properties. Secondly, GFRS can strengthen the endogenous antioxidant defense system, thus lessening the UVB-induced ultraviolet damage that L929 cells and zebrafish experience. Matrix metalloproteinases (MMPs) studies have shown that GFRS could significantly inhibit the UVB-induced MMP1 and MMP9 proteins production. Finally, the main ginsenoside component in GFRS was identified by LC-MS, and 16 kinds of ginsenoside were analyzed, including rare ginsenoside such as Rg6, F4, and R/S-Rg3, which may be caused by the transformation of prototype saponins Re and Rd caused by citric acid heat treatment (CAHT). After doing a quantitative HPLC analysis on twelve of them, it was discovered that CAHT could enrich the content of rare saponins in GFS. By evaluating these ginsenoside’s anti-wrinkle properties. It is found that the main material basis for GFRS’s anti-wrinkle action may be ginsenoside Rg6 or F4. In summary, GFRS exhibits promising properties as an anti-wrinkle treatment because of its robust anti-oxidation, anti-collagenase, anti-elastase activity, favorable ultraviolet absorption effect, and capacity to regulate MMPs in vivo and in vitro models.

Effect of Bisoctrizole on Ultraviolet (UV) Absorption Properties of Silicone and Effect on Surface Roughness - An In Vitro Study.

Premature degradation is the problem of maxillofacial silicones, significantly affected by ultraviolet exposure, contributing to silicones photodegradation. Degradation necessitates frequent replacement of prostheses that increase the total cost of rehabilitation. This study evaluated the effect of bisoctrizole on the ultraviolet absorption properties of silicone material and the stability of this absorption over time. Also, the bisoctrizole effect on the surface roughness of silicone was evaluated. There were 60 prepared specimens of room temperature-vulcanising maxillofacial silicone equally divided into two groups according to the conducted tests: ultraviolet absorption test and the surface roughness test. Each group was further subdivided into groups of 10 specimens based on the weight concentration of the ultraviolet (UV) absorber added: 0%, 1% and 2%. The UV absorbance of coloured specimens was measured before and after artificial weathering for 100 and 200 hours. Repeated-measures analysis of variance (ANOVA) was applied for UV absorption results, and one-way ANOVA was applied for the roughness test results to test the changing significances. Bisoctrizole incorporation led to a highly significant improvement in ultraviolet absorption in all groups, maintaining a high level even after subjecting the specimens to artificial weathering. Furthermore, the addition resulted in a significant increase in surface roughness as the concentration of bisoctrizole increased. Despite the surface roughness changes, bisoctrizole demonstrated efficacy as a UV absorber for maxillofacial silicone, making it valuable for applications such as maxillofacial prosthetics that require UV protection.

A Novel BST@TPU Membrane with Superior UV Durability for Highly Efficient Daytime Radiative Cooling

AbstractPassive radiative cooling technologies play an integral role in advancing sustainable development. While the potential of polymer‐based radiative cooling materials is increasingly recognized, they often degrade under prolonged ultraviolet (UV) radiation exposure, which undermines both their mechanical and radiative cooling performance. To address this challenge, a coaxial electrospinning method to prepare a BST@TPU membrane, with a core layer of strontium barium titanate nanorods (BST NRs) and a shell layer of thermoplastic polyurethane (TPU) is employed. Capitalizing on the UV absorption and free radical adsorption properties of BST NRs, the UV stability of the TPU membrane is significantly increased. Additionally, the inclusion of high refractive index BST NRs compensates for the decrease in reflectivity caused by their UV absorption. After 216 h of continuous 0.7 kW m−2 UV irradiation, the BST@TPU membrane, which initially exhibits a reflectance of 97.2%, demonstrated a modest decline to 92.1%. Its net radiative cooling power maintains 85.78 W m−2 from the initial of 125.21 W m−2, extending the useful lifetime of the TPU membrane threefold. This innovation extends promise for enhancing the efficiency and durability of radiative cooling materials, contributing to sustainable cooling solutions across various applications.

Synergetic construction of color and multifunction for sustainable lyocell fabric by microbial nano pigment

As a kind of low-carbon, environmentally friendly and high-quality regenerated cellulose fiber derived from nature plant, the promotion and application of lyocell fiber is attracting much attention. In this paper, for the first time, microbial pigment was applied for color and multifunction construction of lyocell fabric. The size change of the pigment nano-particles during the color construction process was explored to verify the dyeing mechanism of nano-suspension system, and the optimal dyeing condition was obtained. In order to improve the dyeing effect and functionality of fabric, 1,2,3,4-butanetetracarboxylic acid (BTCA) was used to realize the anionic modification of lyocell fabric with high strength retention rate. Under optimal color construction condition, the color depth of the modified fabric was 298.5% higher than that of the unmodified one, and the dyed fabric possessed excellent dyeing uniformity and permeability. Moreover, the crosslinking reaction between BTCA and cellulose macromolecules, as well as the pigment deposition inside the fibers were helpful to the fibrillation prevention function of lyocell fibers. Dyed fabrics inherited the antibacterial and ultraviolet absorption properties of prodigiosins. The bacteriostatic rate against Staphylococcus aureus was above than 98.5%, and the UV protection performance was obviously improved. This technology successfully realized the color and multi-functional construction of the lyocell fabric in one step by natural pigment from microorganism.

Multicomponent chitosan complex/polyvinyl alcohol blended film with full-band UV-shielding performance and excellent antioxidant property for active food packaging

Utilizing renewable natural resources to construct multifunctional packaging materials is critical to achieving sustainable development in the food packaging industry. In this study, we crafted transparent films with comprehensive UV-shielding and antioxidant properties by blending a multicomponent chitosan complex with polyvinyl alcohol (PVA), subsequently applied to preserve peanut butter. The multicomponent chitosan complex, synthesized from chitosan, ferulic acid (FA), and 5-oxo-3,5-dihydro-2H-thiazolo [3,2-a] pyridine-7-carboxylic acid (TPCA) through direct heating in water, served as the foundation. This chitosan complex was seamlessly blended with PVA, resulting in the creation of a transparent film through the solvent casting method. A meticulous investigation into the chemical structure and physicochemical properties of the blended films was conducted. The FA and TPCA components exhibited robust ultraviolet absorption properties, conferring virtually complete full-band ultraviolet shielding ability to the blend film. Additionally, FA endowed the blended film with significant antioxidant activity. The effectiveness of the chitosan complex/PVA blended film in preserving peanut butter from oxidative spoilage was demonstrated, showcasing its robustness in food preservation. Our research underscores the significance of creating advanced packaging materials from sustainable sources.

Construction of photo-responsive lignin as a broad-spectrum sunscreen agent

Lignin has potential to serve as promising sunscreen agents as it has good ultraviolet (UV) absorption and antioxidant properties. However, the weak absorption capacity of lignin in the long-wave UV region (UVA, 320–400 nm) limits its further development. In this work, a spiropyran-modified lignin (DLSP) with photo-responsive property was prepared by in-situ construction of spiropyran (SP) structure in the demethylated lignin (DL). Due to the presence of SP moiety, the absorption of DLSP in the UVA region was significantly improved. Under UV irradiation, its absorption peak was redshifted as unconjugated SP form isomerized to conjugated merocyanine (MC) form, and the UVA/UVB ratio increased from 0.62 to 0.74. The free-radical scavenging ability of lignin could protect SP from photodegradation, which provided DLSP excellent fatigue resistance. DLSP were blended into creams to investigate its sunscreen performance. Results indicated that DLSP exhibited radiation-enhanced sunscreen performance, the sun protection factor (SPF) of cream containing 10 wt% of DLSP improved from 20 to 67 after 8 h of UV irradiation. Moreover, DLSP showed low skin penetration and good biocompatibility. These results provide a useful guideline for the rational design of sunscreens with special functionalities.

Elucidation of the Genetic Diversity within Some In Situ Shea Germplasm in Ghana

Shea is an agroforestry tree species known primarily for its rich butter, which contains stearin and tocopherol, and has ultraviolet ray absorption property; it is used in cooking, body care and traditional medicines. This tree is, however, uncultivated and collection of its nuts by rural dwellers is threatened by increased urbanization with its accompanying land use pressure and the need for fuel wood for rural households. There is also increased demand for shea products worldwide necessitating the need for shea improvement strategies. At the apex of this improvement program lies the need for germplasm collection, characterization, conservation and utilization. In order to conserve elite shea materials amidst dwindling shea populations threatened by climate change, there is a need to develop shea germplasm banks based on the representation of genetic and phenotypic variation focusing on known traits. The objective of the study was to evaluate 282 shea accessions for germplasm conservation and to determine the genetic diversity of the collected materials to inform future collections and drive crop improvement strategies. Leaf traits were used to differentiate and group the selected materials. Leaf length ranged between 16.83 cm and 30.85 cm, and leaf blade length ranged between 12.28 cm and 20.68 cm. Petiole length varied between 5.53 cm and 10.2 cm and the blade to petiole ratio was from 1.41 to 2.69. Correlation studies revealed significant negative correlation between the latitude of collection and all leaf traits measured. There was significant positive correlation between blade length and petiole length (0.57), blade length and total leaf length (0.87) and petiole length and breadth (0.49). The collected materials were grouped at 90% into two, based on the morphological descriptors studied. Three different approaches were employed to genetically analyze the materials based on single nucleotide polymorphic markers (SNP). A phylogenetic tree was constructed based on the SNPs generated; this grouped the materials into three, with various subgroups. Principal coordinate analysis also produced three distinct groups with groupings not based on geographical area of collection. Discriminant analysis of principal components (DAPC) also confirmed three groupings. The genetic diversity of the collection was very low (Hs) = 0.0406, which is an indication of potential inbreeding within the shea populations. To conclude, there was higher variation within locations than between locations.

Synthesis and characterization of stereolithography3Dprinting fluorescent resin

AbstractIn this study, bisphenol A epoxy resin, 1,6‐Hexanediol diacrylate (HDDA), and 2,4,6‐Trimethylbenzoyl‐diphenylphosphine oxide (TPO) were utilized as a prepolymer, diluent, and photoinitiator, respectively, to prepare a light curing system with different amount of phosphor, which was used in place of conventional inorganic fillers. Phosphor was utilized to improve the precision of the material molded parts during the light curing process and enhance the mechanical properties of the molded parts owing to the ultraviolet (UV) absorption properties of phosphor, which prevented UV damage to the material, thus improving the light aging resistance and stability of the molded parts. Results revealed that the addition of 3% phosphor optimized the mechanical properties of the material (a maximum tensile strength of 42.43 MPa). Additionally, the material achieved the lowest linear (4.1%) and volumetric (0.58%) shrinkage at a phosphor content of 6%. This study provides a new insight into three‐dimensional (3D) printing resin for stereolithography and provides a reference for the improvement of 3D printing products.

The Design, Synthesis and Application of Nitrogen Heteropolycyclic Compounds with UV Resistance Properties.

Exposure to ultraviolet (UV) light is known to cause skin aging, skin damage, cancer, and eye diseases, as well as polymer material aging. Therefore, significant attention has been devoted to the research and development of UV absorbers. Considering the robust hydrogen bonding and conjugated structure present in nitrogen-containing polycyclic compounds, these compounds have been selected as potential candidates for exploring ultraviolet absorption properties. After structural optimization and the simulation of ultraviolet absorption spectra, four tris-[1,2,4]-triazolo-[1,3,5]-triazine (TTTs) derivatives, namely TTTB, TTTD, TTTJ, and TTTL, were selected as the preferred compounds and synthesized. The structure of the compound was determined using various analytical techniques, including FTIR, 1HNMR, 13CNMR, HRMS, and XRD. Subsequently, composite films of polyvinyl chloride (PVC) and TTTs were produced using a simple solvent casting technique. The PVC films were subjected to UV age testing by exposing them to an ultraviolet aging chamber. The age-resistant performance of the fabricated films was evaluated using an ultraviolet spectrophotometer and Fourier infrared spectrum instrument. The findings suggest that TTTs exhibit a noteworthy capacity for absorbing ultraviolet radiation. The TTTL compound exhibits a superior UV absorption performance compared to commercially available UV absorbers such as UV-0 and UV-327 in the market.

Green synthesized TiO2 nanoparticles: Structural characterization and photoinduced antifungal activity against P. steckii

This study synthesized titanium dioxide (TiO2 ) nanoparticles (NPs) from mango leaf extract and investigated the features and antibacterial capabilities of three different. The microscopic morphological observation, scanning electron microscopy, and transmission electron microscopy results showed that all three NPs showed agglomeration phenomenon, and the TN-1 sample existed as large agglomerates, whereas the agglomeration phenomenon of TN-3 sample was improved by the modified, without large agglomerates. The biosynthetic TN-2 and TN-3 NPs were spherical and uniform in size, whereas those of the TN-3 sample was the smallest, ranging from 10 to 30nm. X-ray diffraction and Raman spectroscopy results exhibited that these were highly pure anatase NPs. The result of ultraviolet (UV)-visible-near-infrared spectral analysis showed that the TN-2 and TN-3 samples displayed higher UV absorption properties than the TN-1 samples and were highest in the modified NPs, which was more suitable for preparing chitosan-based nanocomposite material in future experiments and studies. The colony diameters of the TN-1, TN-2, and TN-3 treatment groups were 7.99, 7.80, and 6.86mm, respectively, after 120min of UV light induction at a wavelength of 365nm. Significant differences were evident between the TN-3 and the other two groups (p<0.05), indicating that the TN-3 sample more effectively inhibited Penicillium steckii than the other TiO2 NPs. PRACTICAL APPLICATION: Nanomaterials coated film preservation is widely used in fruit and vegetable preservation. In this paper, TiO2 nanomaterials will be green synthesized using mango leaf and structurally characterized, whereas antibacterial tests will be conducted against the mango fruit-specific bacterium Penicillium steckii, which will provide a theoretical basis for the storage and preservation of mango.

Substituent Effects on the Ultraviolet Absorption Properties of 2,4-Dihydroxy Dibenzophenone

Substituent effects on the ultraviolet absorption properties of 2,4-dihydroxy dibenzophenone were investigated experimentally. Nine compounds of 2,4-dihydroxy dibenzophenone with different substituents were prepared by a solvent-free reaction of benzoyl chloride. The maximum absorption wavelength (λmax) of these samples was measured, and their UV resistance properties in cotton fabric as well as in polyester were determined. The results show that the λmax is dependent on the substituents at the benzylidene ring, and both electron donating substituents and electron withdrawing substituents cause a bathochromic shift. The UV resistance of fabric increases with the increase in compound concentration. The dyeing rate of each compound on polyester was higher than that of cotton. On cotton fabric, the dyeing rate of 2,4-dihydroxybenzophenone was the highest, 77.8%. On polyester, that of 2,4-dihydroxy-4'-ethyl dibenzophenone was the highest, 84.1%. The study provides new insights into the effect of substituents on the properties of 2,4-dihydroxy dibenzophenone that are related to the whitening of cotton and polyester materials.

UV luminescence enhancement of Cu-doped ZnO nanorods grown by hydrothermal treatment

Herein, we studied the effect of Cu doping on the ultraviolet (UV) emission enhancement of ZnO nanorods. ZnO nanorods with different Cu doping concentrations were prepared by hydrothermal method and the Cu doping behavior was investigated by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), ultraviolet visible (UV–Vis) absorption spectroscopy and photoluminescence (PL). XRD patterns confirmed the incorporation of Cu. Compared with pure ZnO, no other phase appears, the intensity of diffraction peaks and the calculated parameters such as lattice constants increase, all of which proved that the doping of Cu is substitutional doping. Doping induces a red-shift in the absorption maximum wavelength of the absorption spectrum, indicating that doping causes attenuation of UV absorption properties. In the PL spectra, the increase of Cu doping concentration makes the UV emission peak enhanced and there is almost no emission peak in the visible region. The UV emission at room temperature can be attributed to the superposition of free and bound excitons, where free excitons dominate and bound excitons are related to the substitution of Cu for Zn. The enhanced UV emission of Cu-doped ZnO materials could lead to the wide application in the field of UV optoelectronic devices.

A metastable Cr4+-compound AlCrO3+δ, δ ≤ 0.5, grown at a nanocolloid, and its ultraviolet absorption, phonon bands, and dielectric properties

AlCrO3+δ, δ ≤ 0.5, is a Cr4+:CrO2 product of a metastable compound of two types Cr4+−3d2 electrons that determine its spin degree of freedom and allied magnetic/optical properties at a magnetic semiconductor. A nanocolloid of Cr6+ bonded via Al3+ and O2– in small micelles (a hydrogel) in water is explored to grow up AlCrO3+δ, δ ≤ 0.5, at hydrothermal reactions at microwave irradiation. It forms hexagonal plates (20–40 nm thickness) as annealed at 500 °C − 1000 °C (microwave). It has 4.69% larger X-ray crystal density of 4.848 g/cm3 than a usual phase, AlCrO3.5 → AlCrO3 + ¼O2↑, turned up on anneals at ≥ 1000 °C, at a larger bandgap, ≥ 4.2 eV, of a Cr3+−3d3 insulator. X-ray diffraction, XPS, electronic absorption, and phonon bands studied at duly annealed samples confer a Cr5+ → Cr4+ → Cr3+ charge ordering at anneals. A 700 °C annealed sample (others behave as an antiferromagnet, AFM) exhibits a ferromagnetic (FM) loop, with an unsaturated magnetization 9.2 emu/g (at 50 kOe fields), a coercivity 3.67 kOe, and a 0.1 MGOe energy-product at room temperature. The two types FM−AFM spins channels govern electrical conduction at major charge carriers Cr4+ → Cr3+ − e–, O2– vacancies, and ‘e–−h+’ electron-hole pairs as per applied frequencies. The results have renewed interest to design and develop spintronics-photonics at Cr4+−3d2 spin doped Al2O3 type oxides.

Nanoarchitectonics of (110) directed polyethylene glycol stabilized cerium nanoparticles for UV filtering applications

The use of zinc oxide (ZnO) and titanium oxide (TiO2) nanoparticles in ultraviolet (UV) filters can cause serious health issues due to their genotoxicity and cytotoxicity effect. Recent research on cerium oxide (CeO2) nanoparticles has demonstrated their biocompatible nature, excellent antioxidant and ultraviolet–visible (UV–Vis) absorption properties. CeO2-based nanocomposite materials or nano-architectures can offer uniform absorptive properties, therapeutic skin effect and easy skin application. In this study, cerium oxide-polyethylene glycol (CeO2-PEG) nano-architecture was prepared by hydrothermal processing with the aim to improve stability, antioxidant properties, and enhance UV absorption for UV filtering applications. The morphology study of the developed nanocomposite revealed the formation of polymer bands with well-dispersed CeO2 nanoparticles. The nanocomposite structure has exhibited excellent UV absorption in the UV range 200–400 nm due to decrease in optical band gap in comparison to the naked CeO2 NPs. The evaluation of the photocatalytic activity (PCA) of the nanocomposite structure against P25 photocatalyst and ZnO nanoparticles showed no dye (crystal violet) degradation on UV irradiation. Hence, PCA assay verified the absence of ROS generation and increased stability of the nanostructure under UV irradiation. The investigation of antioxidant properties of the Ce-PEG nanocomposite by a dichlorofluorescein (DCF)-based assay revealed sufficient intracellular ROS scavenging in comparison to N-acetylcysteine (NAC) and H2O2 only assays. In vitro toxicity evaluation of Ce-PEG nanocomposite towards non-malignant human keratinocyte cell line (HaCaT) revealed a non-significant cell mortality ~ 10% of control at a dosage of 50 mg L−1. The nanocomposite structure also exhibited excellent UV protection for HaCaT cells under UV irradiation conditions compared to P25. Our findings suggest that the developed nanocomposite combined the antioxidant and UV absorption properties of CeO2 and skin emollient role of (PEG), and hence offered a novel biocompatible and multifunctional structure for sunscreens and therapeutic skin product.Graphical abstract

Rational design direct Z-scheme β-GeSe/HfS2 heterostructure by interfacial engineering: Efficient photocatalyst for overall water splitting in the wide solar spectrum

The direct Z-scheme van der Waals (vdW) heterostructures that mimic the natural photosynthesis in plants raise a tremendous concern for photocatalysis applications. Herein, we propose a novel two-dimensional (2D) heterostructure comprised of HfS2 and β-GeSe monolayers. The most stable stacking configuration of the β-GeSe/HfS2 heterostructure is identified by using formation energy and molecular dynamic simulations. The direct Z-scheme photocatalytic property of the β-GeSe/HfS2 heterostructure was identified from band alignment, charge transfer, and built-in electric field. The β-GeSe/HfS2 heterostructure has a robust and excellent visible and ultraviolet optical absorption property (up to 105 cm−1). Moreover, the overall decomposition of water can proceed simultaneously and spontaneously on the surface of β-GeSe/HfS2 heterostructure when pH in the ranges from 7 to 12, without additional overpotential and co-catalyst. The highest solar-to-hydrogen (STH) efficiency of the heterostructure reaches 37.95%. This work not only provides a stepping stone into the design of high efficient Z-scheme photocatalyst but also demonstrates the enormous possibilities in two-dimensional heterostructures.

Chemical Transformation of Lignosulfonates to Lignosulfonamides with Improved Thermal Characteristics

Lignin is an abundantly occurring aromatic biopolymer that receives increasing attention as, e.g., a biofiller in polymer composites. Though its structure depends on the plant source, it is a valuable component showing biodegradability, antioxidant, and ultra-violet (UV) absorption properties. Lignosulfonates, a by-product of the paper and pulping industries formed as a result of the implementation of the sulfite process, have been used in the presented study as a raw material to obtain a sulfonamide derivative of lignin. Hereby, a two-step modification procedure is described. The obtained materials were investigated by means of FTIR, WAXD, SS-NMR, SEM, and TGA; the results of spectroscopic investigations confirm the formation of a sulfonamide derivative of lignin via the proposed modification method. The obtained modified lignin materials showed significantly improved thermal stability in comparison with the raw material. The internal structure of the lignosulfonate was not altered during the modification process, with only slight changes of the morphology, as confirmed by the WAXD and SEM analyses. The manufactured sulfonamide lignin derivatives show great promise in the potential application as an antibacterial filler in advanced biopolymeric composites.