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Structural parameters play a crucial role in determining the electromagnetic and thermal responses of gold nanoconstructs (GNCs) at near-infrared (NIR) wavelengths. Therefore, developing GNCs for reliable, high-contrast photoacoustic imaging has been focused on adjusting structural parameters to achieve robust NIR light absorption with photostability. In this study, we introduce an efficient photoacoustic imaging contrast agent: gold sphere chains (GSCs) consisting of plasmonically coupled gold nanospheres. The chain geometry results in enhanced photoacoustic signal generation originating from outstanding photothermal characteristics compared to traditional gold contrast agents, such as gold nanorods. Furthermore, the GSCs produce consistent photoacoustic signals at laser fluences within the limits set by the American National Standards Institute. The exceptional photoacoustic response of GSCs allows for high-contrast photoacoustic imaging over multiple imaging sessions. Finally, we demonstrate the utility of our GSCs for molecular photoacoustic cancer imaging, both in vitro and in vivo, through the integration of a tumor-targeting moiety.

In vivo fluorescent imaging in the second near‐infrared window (NIR‐II) provides an excellent approach for understanding the biological processes in substantially scattered tissue environments with reasonable temporal‐spatial resolution. In spite of an enormous amount of organic and inorganic NIR‐II fluorophores developed, there are no reported NIR‐II fluorescent protein. Here, the first NIR‐II fluorescent protein is presented, IRFP1032, which exhibits strong exciton absorption and emission in the NIR‐II region, with exciton extinction coefficient about 4.1 × 106 M−1cm−1 at the excitation maximum 1008 nm, emission maximum of 1032 nm, and emission quantum yield about 0.84%. The IRFP1032 is found to be one of the brightest NIR‐II fluorophores ever reported (brightness of 3.4×104 M−1cm−1 in PBS), thousands‐fold brighter than IR26 in DCM. Furthermore, the IRFP1032 exhibits an ultra‐photostability in comparison to small organic fluorophore. Taking the advantage of the excellent photophysical properties of the NIR‐II fluorescent protein, high‐quality in vivo imaging is realized, for instance, real time observation of blood flow dynamics, dual‐channel imaging of the lymphatic/blood vessel network, and the trajectories of single bacterial cell travelling in blood vessels. The promising NIR‐II in vivo imaging properties demonstrated here with IRPF1032 can open a new scene in fluorescent protein‐based imaging. [ABSTRACT FROM AUTHOR]

Poor operational stability is a crucial factor limiting the further application of perovskite solar cells (PSCs). Organic semiconductor layers can be a powerful means for reinforcing interfaces and inhibiting ion migration. Herein, two hole‐transporting molecules, pDPA‐SFX and mDPA‐SFX, are synthesized with tuned substituent connection sites. The meta‐substituted mDPA‐SFX results in a larger dipole moment, more ordered packing, and better charge mobility than pDPA‐SFX, accompanying with strong interface bonding on perovskite surfaces and suppressed ion motion as well. Importantly, mDPA‐SFX‐based PSCs exhibit an efficiency that has significantly increased from 22.5 % to 24.8 % and a module‐based efficiency of 19.26 % with an active area of 12.95 cm2. The corresponding cell retain 94.8 % of its initial efficiency at maximum power point tracking (MPPT) after 1,000 h (T95=1,000 h). The MPPT T80 lifetime is as long as 2,238 h. This work illustrates that a small degree of structural variation in organic compounds leaves considerable room for developing new HTMs for light stable PSCs. [ABSTRACT FROM AUTHOR]

In recent years, self‐assembled monolayers (SAMs) have been proven to work efficiently as hole‐selective materials in both organic solar cells (OSCs) and perovskite solar cells. Although competitive performances are reported with these materials, a mechanistic understanding on device stability remains elusive. This study reveals that while various SAM molecules can increase the indium tin oxide (ITO) work function versus vacuum, they may not consistently result in monolayers that ensure simultaneous improvement in performance and operational stability of devices. Energetically, achieving alignment between the work function of the SAM‐modified electrode and the ionization energy (IE) of the donor is shown to be crucial for a low hole injection barrier, irrespective of the SAM's IE. Light‐induced degradation in the widely used SAM, (2‐(9H‐carbazol‐9‐yl)ethyl) phosphonic acid (2PACz), is identified through diverse aging tests and comprehensive chemical and electronic characterizations. This degradation involves SAM molecule decomposition and chemical reactions with the photoactive layer, contributing further to device degradation. Addressing these challenges, sputtered nickel oxide/SAM bilayers are proposed as hole‐selective contact with tailored interface energetics for both efficient and photostable OSCs, offering a promising alternative to commonly used hygroscopic PEDOT:PSS in OSCs. [ABSTRACT FROM AUTHOR]

As family members of polycyclic aromatic hydrocarbons, compound anthracene (Ant) and phenanthrene (Phe) as isomers are widely used in organic optical materials and electronic materials. But their photochemical and physical properties are very different. In this work, the room temperature phosphorescence (RTP) properties of PVA−B‐Ant and PVA−B‐Phe are discussed carefully which are prepared by B−O click reaction through polyvinyl alcohol (PVA) with 9‐anthraceneboronic acid (B‐Ant) and 9‐phenanthrenylboronic acid (B‐Phe), respectively. PVA−B‐Phe 1 % film exhibits excellent fluorescence (FL) emission at 374 nm and RTP emission at 523 nm with green afterglow and around 1.9 s phosphorescence lifetime. However, PVA−B‐Ant 1 % film only shows strong blue FL emission at 414 nm, and the emission intensity decreases seriously with the extension of irradiation time. Experimental and theoretical calculations results suggest that the photodimer of Ant which is formed in PVA matrix under the UV light irradiation would be competitive with the process of RTP emission. This work demonstrates that the RTP properties of organic molecules might be probably affected by the photostability of the organic phosphor under UV irradiation. [ABSTRACT FROM AUTHOR]

Lanthanide‐based upconversion molecular complexes have potential application in diverse fields and attracted considerable research interest in recent years. However, the similar coordination reactivity of lanthanide ions has constrained the designability of target molecule with well‐defined structure, and many attempts obtained statistical mixtures. Herein, an ion‐paired Yb−Eu heteronuclear complex [Eu(TpPy)2][Yb(ND)4] (TpPy=tris[3‐(2‐pyridyl)pyrazolyl]hydroborate, ND=3‐cyano‐2‐methyl‐1,5‐naphthyridin‐4‐olate) was designed and synthesized. Thanks to the radius difference between Eu3+ (1.07 Å) and Yb3+ (0.98 Å) ions, the hexadentate TpPy ligand was selected to coordinate with Eu3+ and the Yb3+ with a smaller radius was chelated by bidentate ND ligand. As a result, the sites of Eu3+ and Yb3+ in the complex can be clarified by high‐resolution mass spectrometry and single‐crystal structure analysis. Upon the excitation of Yb3+ at 980 nm, the upconversion emission of Eu3+ was realized through a cooperative sensitization process. Furthermore, [Eu(TpPy)2][Yb(ND)4] demonstrated excellent photostability during continuous high‐power density 980 nm laser irradiation, with a LT95 (the time to 95 % of the initial emission intensity) of 420 minutes. This work provides the first example of a pure ion‐paired Yb−Eu heteronuclear complex upconversion system and may bring insights into rational design of lanthanide‐based upconversion molecular complexes. [ABSTRACT FROM AUTHOR]

This research aims to develop the inclusion complex of 2, 4‐diamino‐6‐hydroxypyrimidine (DHP) with β‐cyclodextrin (β‐CD) using an inclusion process, and to investigate the effect of inclusion on the photo stability and bioactivity of DHP. The formation of DHP‐β‐CD inclusion complex has been examined by means of physicochemical as well as spectroscopic techniques (1H NMR, FT‐IR, PXRD and SEM) suggesting the successful inclusion of the DHP molecule into the β‐CD cavity. The 1 : 1 stoichiometry of the inclusion complex was validated through Job's plot. β‐CD displayed a fairly strong affinity (Ka =889.67 M−1) for DHP, indicating that the binding process is thermodynamically feasible. A molecular docking study speculated the most preferred orientation of DHP molecule within the binding pocket of β‐CD cavity. The photostability of DHP was found to improve on complexation with β‐CD. In vitro antibacterial activity test demonstrated that the DHP‐β‐CD inclusion complex displayed better activity than pure DHP. DHP‐β‐CD inclusion complex (IC50 =240.04 μM) also exhibited relatively significant in vitro cytotoxic activity than pure DHP towards the human kidney cancer cell line (ACHN). These results reveals that the inclusion of DHP using β‐CD could lead to stabilization of DHP and efficient display of its bioactivity. [ABSTRACT FROM AUTHOR]

Overexposure to blue light due to the excessive use of electronic devices has been implicated in premature skin aging and eye damage, among other injuries to health. This study aimed to synthesize two azo derivatives of the 2‐(amino‐2′‐hydroxyphenyl) benzoxazole and explore their potential as UV and blue light filters, proposing a new spectral profile. The synthesis of the heterocyclic compounds involved condensation reactions and diazotation. The derivatives 2‐(benzoxazol‐2‐yl)‐5‐[(2‐hydroxynaphthyl)diazenyl]phenol and 2‐(benzoxazol‐2‐yl)‐4‐[(2‐hydroxynaphthyl)diazenyl]phenol were synthesized with a yield greater than 70%. Solubility was evaluated in seven different solvents. The maximum absorption wavelengths (λmax) were determined using UV–Vis scanning spectrophotometry in the range of 200–600 nm. Photostability was assessed using a solar simulator and the Sun protection factor (SPF) was determined using in vitro methodology. Cytotoxicity was evaluated using the MTT assay in V79 cells. These compounds were able to absorb UVA, UVB, and blue light, with λmax ranging from 300 to 500 nm and demonstrated photostability after 3 h of exposure to solar simulator with an SPF higher than 45. The compounds exhibited solubility in all lipophilic solvents tested. Regarding cytotoxicity, IC50 values were comparable to other filters. These findings indicate that both compounds hold promise as potential organic filters. [ABSTRACT FROM AUTHOR]

In the present study, biocomposite materials were created by incorporating biochar (BC) at rates of 1, 2.5, and 5 wt.% into a poly(butylene succinate) (PBSu) matrix using a two-stage melt polycondensation procedure in order to provide understanding of the aging process. The biocomposites in film form were exposed to UV irradiation for 7, 14, and 21 days. Photostability was examined by several methods, such as Fourier transform infrared spectroscopy (FTIR), which proved that new carbonyl and hydroxyl groups were formed during UV exposure. Moreover, Differential Scanning Calorimetry (DSC) measurements were employed to record the apparent UV effect in their crystalline morphology and thermal transitions. According to the molecular weight measurements of composites, it was apparent that by increasing the biochar content, the molecular weight decreased at a slower rate. Tensile strength tests were performed to evaluate the deterioration of their mechanical properties during UV exposure, while Scanning Electron Microscopy (SEM) images illustrated the notable surface alternations. Cracks were formed at higher UV exposure times, to a lesser extent in PBSu/BC composites than in neat PBSu. Furthermore, the mechanism of the thermal degradation of neat PBSu and its biocomposites prior to and upon UV exposure was studied by Pyrolysis–Gas Chromatography/Mass Spectrometry (Py–GC/MS). From all the obtained results it was proved that biochar can be considered as an efficient UV-protective additive to PBSu, capable of mitigating photodegradation. [ABSTRACT FROM AUTHOR]

The study examined the photo-stability of the thermal control coating (TCC), a class of "Optical Solar Reflectors", used in spacecrafts. This TCC is achieved by applying a layer of dielectric ceramic paste (DCP) onto the substrate using a printer (PCB printing). The DCP was prepared from filler (ground Al 2 O 3 ceramic) and solvent with thickener (terpineol with ethylcellulose). The coating obtained by high-temperature firing (T = 850 оC, 2 h) has high reflectivity in the solar range of the spectrum (0.2–2.5 μm) with the solar absorptance (α s) of DCP equal to 0.143. It has high adhesion and photo-stability that exceeds photo-stability parameters of ZnO, TiO 2 , BaSO 4 , and CaSiO 3 pigments. The developed coating can be recommended not only as a TCC for spacecrafts, but also as a protective or dielectric layer in manufacturing of printed circuit boards in various fields of technology, where increased resistance to solar radiation or its ultraviolet region is required. [ABSTRACT FROM AUTHOR]

Recently, giant quantum dots (g‐QDs) with a core/interface graded alloy shell/shell structure have shown promise in reducing photoluminescence (PL) intermittency and improving photostability. However, this approach has been mainly demonstrated with red and green emitting g‐QDs but the blue‐emitting graded alloy QDs has remained less explored. To tackle this challenge, a composition gradient method is employed to create three blue‐emitting CdZnS/CdxZn1–xS/ZnS core/interface graded alloy shell/shell (C/A/S) quantum dots (QDs) with different diameters. The sample with the largest diameter (gQD‐3) exhibits superior optical characteristics, with a photoluminescence quantum yield (PLQY) of approximately 62% and around 80% ON/radiative events at the single‐particle level. Conversely, the smallest diameter (gQD‐1) sample shows lower PLQY and only 30% radiative events with longer OFF/nonradiative events. Probability distribution analysis of PL trajectories, fitted with a truncated power law, reveals a significantly higher carrier de‐trapping rate in gQD‐3 compared to gQD‐1, attributed to its proximity to band edge trap states. Additionally, the largest diameter sample retains remarkable optical performance during 48 h of continuous UV irradiation in colloidal suspension and single‐particle levels. These findings show optimized core/shell structures, gradual alloy interfaces, and outer shell coatings can stabilize blue‐emitting quantum dots, advancing next‐gen optoelectronics. [ABSTRACT FROM AUTHOR]

Large voltage deficit and photoinduced halide segregation are the two primary challenges that hinder the advancement of wide‐bandgap (WBG) (Eg ≥ 1.65 eV) perovskite solar cells (PSCs). Herein, a cation engineering approach to enhance the optoelectronic properties of formamidine–cesium (FA‐Cs) WBG perovskites by incorporating methylamine (MA) as the third cation is presented. Three perovskite species with a bandgap of 1.68 eV, abbreviated as Cs0.05, Cs0.15, and Cs0.25, are systematically studied by optimizing the MA content. The incorporation of MA is found to effectively enhance the crystallinity and improve the carrier lifetimes of the three perovskite species. Moreover, the microstrain in the FA‐MA‐Cs perovskite films is significantly reduced due to the buffer effect of MA between the size‐mismatched FA and Cs, a benefit derived from the cascade cation design. The optimized compositions for the three species are Cs0.05MA0.2FA0.75PbI2.58Br0.42, Cs0.15MA0.1FA0.75PbI2.68Br0.32, and Cs0.25MA0.03FA0.72PbI2.73Br0.27, respectively. Among these, Cs0.25MA0.03FA0.72PbI2.73Br0.27 perovskite stands out due to its high crystallinity, low microstrain, and low trap density, giving rise to the highest efficiency of 20.64% with the lowest voltage loss. This perovskite also exhibits superior air, light, and thermal stability. These findings underscore the importance of rational cation design in achieving efficient and photostable WBG PSCs. [ABSTRACT FROM AUTHOR]

Aim: To ascertain the impact of shape and surface modification of anisotropic nanoparticles on the toxicity and photothermal efficiency toward cancerous cell lines. Methods: Gold nanobipyramids and nanostars surface modified with MUC1 aptamer were used in the current study to explore the toxicity and photothermal efficiency on MCF7 breast cancer cell lines via MTT assay. Results: Surface functionalization with MUC1 aptamer showed significant reduction in % cytotoxicity and increase in % specific internalization of nanostructures into MCF7 cell lines. Further, the photothermal studies accomplished at IC50 concentration for 6 h of treatment and laser exposure for 15 min reported that aptamer-conjugated nanobipyramids were more effective and specific toward MCF7 cell lines than aptamer-conjugated nanostars. Conclusion: This work establishes a platform for the development of tailored photoablation based gold nanostructures for in vivo studies. Article highlights The investigation on cytotoxic effects and photothermal efficiency of anisotropic spiked gold nanostructures are requisite. Gold Nanostars (GNS), nanobipyramids (GNB) possess exceptional tip-enhanced plasmonic characteristics. GNB and GNS were synthesized and surface modified with MUC1 aptamer. GNB and GNS exhibited photothermal conversion efficiency of 14.5 and 14.1%, respectively. GNB and GNS are much less cytotoxic after aptamer conjugation. Compared with aptamer-GNS, aptamer-GNB exhibited higher selective cellular internalization toward MCF7 cell lines. Photoablation studies revealed that MCF7 cell lines were more severely damaged by aptamer-GNB than by aptamer-GNS. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSCs) have witnessed a meteoric rise in device performance. However, maintaining photostability, particularly under thermal stress, remains a challenge due to defect formation in the perovskite layer. This study introduces europium (III) trifluoromethanesulfonate [Eu(OTF)3] as a multifunctional additive in two‐step processed perovskite films, significantly improving the performance and high‐temperature photostability of n‐i‐p PSCs. Density function theory (DFT) calculations reveal that the OTF− anion strongly coordinates with Pb2+, effectively inhibiting iodine vacancy defect formation. The addition of Eu(OTF)3 promotes perovskite grain growth to ≈2 µm and enhances film crystallinity. PSCs with a structure of ITO/SnO2/perovskite/PDCBT/NiOx/Au achieve a champion power conversion efficiency (PCE) of 23.8%. Under 85 ± 5 °C and 1 sun illumination at an open circuit in ambient air, the PSCs with Eu(OTF)3 retain 82% of their initial PCE after aging for 1500 h. [ABSTRACT FROM AUTHOR]

In the past few years, there has been an increasing interest in mycosporines—UV-absorbing molecules—bringing important insights into their intrinsic properties as natural sunscreens. Herein, mycosporine-serinol and gadusol (enolate form)/gadusolate were exposed to UV radiation via a solar simulator and the photostability was assessed in pure water and different natural matrices like river, estuary and ocean water. In general, this study revealed that the photodegradation of gadusolate and mycosporine-serinol was higher in natural matrices than in pure water due to the generation of singlet oxygen on UV irradiation. In pure water, in terms of photostability, both gadusolate and mycosporine-serinol were found to offer good protection and high performance in terms of photodegradation quantum yield ((0.8 ± 0.2) × 10−4 and (1.1 ± 0.6) × 10−4, respectively). Nonetheless, the photostability of mycosporine-serinol was found to be superior to that of gadusolate in natural water, namely, ocean, estuary and river. The present work highlights how mycosporine-serinol and gadusolate resist photodegradation, and supports their role as effective and stable UV-B sunscreens. [ABSTRACT FROM AUTHOR]

INTRODUCTION. The stability assessment of biological medicinal products (BMPs) requires special approaches and regulatory requirements. Therefore, BMPs require relevant national guidelines, which are an important prerequisite for the assurance of the safe and effective use of BMPs.AIM. This study aimed to analyse national and international requirements for the stability assessment of BMPs in order to use the results to inform future development of a unified regulatory approach to estimating and confirming shelf-life periods for BMPs.DISCUSSION. Most biotechnological medicinal products (BTMPs) are proteins and are highly sensitive to environmental factors by nature. Therefore, the shelf life of a BTMP is established on the basis of real-time stability studies. Stability testing under accelerated and stress conditions is conducted to support shelf-life claims and to characterise the mechanism of protein structure degradation. The results of accelerated and stress studies can be used to select the most sensitive stability-indicating parameters and testing methods. National and international regulatory authorities have developed specialised guidelines for stability studies of BMPs of various origins, and the stability assessment approaches in the regulatory system of the Eurasian Economic Union (EAEU) are harmonised with international standards. Special considerations associated with the stability of vaccines imply that stability studies of vaccines should not only establish shelf life but also investigate stability after reconstitution and after short-term temperature excursions from the recommended cold-chain conditions.CONCLUSIONS. Special stability testing considerations for various groups of BMPs (including BTMPs and immunobiologicals) indicate the need to develop and improve the system of requirements for BMP stability assessment. This will facilitate the optimisation of the life cycle of BMPs in the Russian Federation and the other EAEU member states.

Manidipine (MP) is widely used for reducing high blood pressure. Calslot® (CALS) tablets, which are the original MP medicines, and their generic medicines have been used for patients in clinical situations. The authors hypothesized that the photodegradability of MP drug substance in CALS tablets might be enhanced when the tablets were photo-exposed after the change of the dosage form by the presence of riboflavin (RF), which is utilized as a coloring agent and a well-known photosensitizer. The present study clarified that RF enhanced the photodegradation of MP when the powders and the suspensions of CALS tablets were ultraviolet light (UV) irradiated. The addition of RF to the suspension of MP standard substances also promoted MP photodegradation along with the increase of the generation rate of its main photoproduct, benzophenone. Finally, the authors performed the photostabilization of MP suspensions based on the addition of quercetin (QU), which is one of polyphenols and has both the antioxidative potency and the UV filtering potency. It is summarized that QU has a protective potency for MP’s own photodegradation, and it partially suppresses the photocatalytic effect of RF. Further studies focused on the photochemical behaviors of utilized additives for medicines are needed for their safe use.

Bixin is used in wide-ranging food applications but is susceptible to degradation by many factors, including light. This research aims to increase bixin photostability through metal complexation. Bixin was complexed with Mg2+, Ca2+, Zn2+, and Se4+. The synthesis process was carried out in deep eutectic solvent media. Metal-bixin complexes have been successfully synthesized, indicated by the change in retention factor and %III/II ratio values resulting from thin-layer chromatography and UV-vis spectrophotometer analysis, respectively. The Fourier transform infrared analysis showed the interaction between central metal ion with bixin ligand has occurred by hydroxyl and carbonyl groups of bixin, which was characterized by a decrease in the intensity of the absorption peak in wavenumber 3000–4000 cm−1 (for the –OH carboxylic group vibration) and the peak shift of metal-bixin complexes towards the larger compared to bixin in the range wavenumber 1600–1700 cm−1 (for C=O ester vibrations). First-order photodegradation kinetics studies showed that the metal-bixin complexes were more stable than pure bixin. Se-bixin was four times more stable than pure bixin. Complexation of bixin with metals was shown to be a potential method to increase the stability of bixin, especially against light exposure.

Chlorophyll (Chl), the most widely distributed natural pigment in nature, is limited in use due to its poor stability. This study refers to the aggregation structure of Chl and carotene (Car) in natural photosynthetic systems, hoping to improve the photostability of Chl by constructing Chl/Car aggregates. The stability protection effect of Car on Chl was explored by designing different ratios of Chl and Car aggregation systems. The configuration of Chl/Car aggregates was optimized through ab initio molecular dynamics, and the aggregation mechanism of the aggregates and the photoprotection mechanism of Chl by Car were elucidated through quantum chemical calculations and wave function analysis. Chl/Car had a 27.22% higher Chl retention rate than free Chl after 7 d of illumination, with a Chl to Car ratio of 1.66:1. A configuration of the Chl/Car aggregates which Car's conjugated olefin chain interacts extensively with the porphyrin ring and bent phytyl chain of Chl made them more stable. The photoprotective mechanism of Car on Chl in the Chl/Car aggregates is elucidated. Car's conjugated polyene chain provides HOMO orbitals to the Chl/Car aggregates. It demonstrated that Car supplies electrons in the low-lying excited states S2 and S4, indicating it is more susceptible to damage, protecting Chl. This research will promote the development of natural color formulas and ensure the health of consumers.

Organic-inorganic hybrids are next-generation materials for use in high-performance optoelectronic devices owing to their adaptabilities in terms of design and properties. This article reviews the application of hybrid materials and layers in several widely used optoelectronic devices, i.e., light amplification by stimulated emission of radiation (LASER), solar cells, and light-emitting diodes (LEDs). The effects of the incorporation of inorganic particles on photostability and optical gain are analyzed in the first section with reference to dye and perovskite lasers. Second, the strategies used in blending inorganic nanostructures into organic solar cells and bulk heterojunctions are analyzed. The use of various organic layers as electron- and hole-transport materials in Si heterojunction solar cells is reviewed in detail. Finally, the benefits of the presence of organic components in quantum-dot- and perovskite-based LEDs are derived from the analysis. The integration of organic and inorganic components with optimal interfaces and morphologies is a challenge in developing hybrid materials with improved efficiencies.

Quantum dot (QD)‐based luminescent solar concentrators (LSCs) promise to revolutionize solar energy technology by replacing building materials with energy‐harvesting devices. However, QDs degrade under air, limiting the long‐term performance of QD‐LSCs. This study introduces an innovative approach to prevent QDs degradation by utilizing a photoactive polymer matrix (maleic anhydride‐grafted poly(styrene‐b‐ethylene‐co‐butylene‐b‐styrene, SEBS‐g‐MA). This strategy has been tested outdoors over a 2‐year period on five LSCs, followed by characterization of the weathered devices. The tested LSCs consist of three QD‐LSCs (CuInS2/ZnS, InP/ZnSe/ZnS, CdSe/CdS/ZnS core/shell QDs), alongside a Lumogen dye‐based LSC and a luminophore‐free LSC. The study yields several findings: 1) SEBS‐g‐MA undergoes photochemistry outdoors, 2) SEBS‐g‐MA accelerates the photodegradation of Lumogen, 3) the power conversion efficiency of CdSe‐based QD‐LSC drops by 80% due to reduction of the photoluminescence quantum yield, and 4) under illumination SEBS‐g‐MA protects CuInS2 and InP‐based QDs from degradation, ensuring a stable performance during the entire study. This work thus demonstrates for the first time that the interaction between the luminophores and the matrix is a critical determinant of the long‐term success of LSCs. Leveraging on the fact that this is the longest outdoor study to date, we propose design rules for highly efficient and stable QD‐LSCs. [ABSTRACT FROM AUTHOR]

For the use of polymeric electrochromic devices (ECDs) in architectural or automotive applications, the photostability of the electrochromic (EC) polymer is crucial for long‐term durability. In this study, the photostability of the side‐chain modified poly(3,4‐ethylenedioxythiophene) (PEDOT‐EthC6)thin films deposited by roll‐to‐roll slot‐die coating on indium tin oxide coated polyethylene terephtalate (PET‐ITO) is investigated and characterized by UV–vis and IR spectroscopy. Residual iron salt on the EC polymer layer, necessary for the in situ polymerization, and the variation of storage times between processing steps have no influence on the degradation rate during light exposure. The photostability of the thin films is 30% better in an inert atmosphere than in ambient conditions. Different long‐pass filters are applied to enhance the photostability in the colored and the bleached state. The position of the absorption edge strongly affects the photostability and visual appearance/color of the PEDOT‐EthC6 electrodes. The analysis of the CIE L*a*b* color coordinates reveals that a trade‐off between stability and a desirable color is necessary. To prevent UV degradation of the EC polymer in flexible ECDs, sputtered nickel oxide is chosen as the counter electrode material. The hybrid ECD shows no sign of degradation and loss of electrochromic performance after 350 h of light exposure. [ABSTRACT FROM AUTHOR]

The development and use of interface materials are essential to the continued advancement of organic solar cells (OSCs) performance. Self‐assembled monolayer (SAM) materials have drawn attention because of their simple structure and affordable price. Due to their unique properties, they may be used in inverted devices as a modification layer for modifying ZnO or as a hole transport layer (HTL) in place of typical poly(3,4‐ethylenedioxythiophene)‐poly(styrenesulfonate) (PEDOT:PSS) in conventional devices. In this work, zinc oxide (ZnO) is modified using five structurally similar SAM materials. This resulted in a smoother surface, a decrease in work function, a suppression of charge recombination, and an increase in device efficiency and photostability. In addition, they can introduced asfor hole extraction layer between the active layer and MoO3, enabling the use of the same material at several functional layers in the same device. Through systematic orthogonal evaluation, it is shown that some SAM/active layer/SAM combinations still offered device efficiencies comparable to ZnO/SAM, but with improved device' photostability. This study may provide recommendations for future SAM material's design and development as well as a strategy for boosting device performance by using the same material across both sides of the photoactive layer in OSCs. [ABSTRACT FROM AUTHOR]

Manidipine (MP) is widely used for reducing high blood pressure. Calslot® (CALS) tablets, which are the original MP medicines, and their generic medicines have been used for patients in clinical situations. The authors hypothesized that the photodegradability of MP drug substance in CALS tablets might be enhanced when the tablets were photo-exposed after the change of the dosage form by the presence of riboflavin (RF), which is utilized as a coloring agent and a well-known photosensitizer. The present study clarified that RF enhanced the photodegradation of MP when the powders and the suspensions of CALS tablets were ultraviolet light (UV) irradiated. The addition of RF to the suspension of MP standard substances also promoted MP photodegradation along with the increase of the generation rate of its main photoproduct, benzophenone. Finally, the authors performed the photostabilization of MP suspensions based on the addition of quercetin (QU), which is one of polyphenols and has both the antioxidative potency and the UV filtering potency. It is summarized that QU has a protective potency for MP's own photodegradation, and it partially suppresses the photocatalytic effect of RF. Further studies focused on the photochemical behaviors of utilized additives for medicines are needed for their safe use. [ABSTRACT FROM AUTHOR]

Ethiprole (ETH) is a phenylpyrazole insecticide that is used worldwide as an alternative to fipronil (FIP). Research on the photodegradation of ETH in aquatic environments has been limited compared with that on FIP. In this study, to clarify the photodegradation of ETH in aquatic systems, the photodegradation pathway and products were investigated using liquid chromatography and liquid chromatography-tandem mass spectrometry. We also determined the photochemical half-lives (t1/2) of ETH and its main degradation products. The primary photodegradation pathway was cyclization/dechlorination and hydroxylation/dechlorination of ETH to form the didechlorinated products (benzimidazole of des-chloro-hydroxy-ETH). Some newly identified photodegradation products and analogs of FIP photodegradation products were also detected as minor products. We compared the photodegradation of ETH with that of FIP under the same conditions. Didechlorinated products of ETH and FIP had the highest photostability. However, although the photochemical t1/2 of EHT was 2.7 times that of FIP, the photochemical t1/2 of the didechlorinated product of ETH was approximately one-third that of the didechlorinated product of FIP. This comparison of the photochemical processes of ETH and FIP provides new insight into the persistence and characteristics of both insecticides in the environment. [ABSTRACT FROM AUTHOR]

The photodecomposition behavior of cationic porphyrin ZnTMAP4+ (zinc tetrakis-(N,N,N-trimethylanilinium-4-yl) porphyrin) in water and complexed with clay nanosheets was investigated by light irradiation to the Soret band of ZnTMAP4+. The decomposition of ZnTMAP4+ was observed by UV–visible absorption spectroscopy. While the decomposition quantum yield (ϕdec) was 3.4 × 10−4 in water, that was 9.4 × 10−7 on the exfoliated clay nanosheets. It was revealed that the photostability of ZnTMAP4+ was stabilized by the complex formation with clay. When ZnTMAP4+ was intercalated between the stacked clay nanosheets, ϕdec was further decreased to 4.9 × 10−7. The photostability increased by 361 times and 693 times for the exfoliated and stacked state, respectively. These results indicate that the flat clay surface has the potential to control intra- and intermolecular photochemical reactions. [ABSTRACT FROM AUTHOR]

Indocyanine Green (ICG) as an agent for photodynamic therapy (PDT) of melanoma cancer has low quantum yield, short circulation half-life, poor photo-stability, and tendency to aggregation. N-doped carbon quantum dot (CQD) nanoparticle was applied to encapsulate ICG and overcome ICG obstacle in PDT with simultaneous cell imaging property. CQD was prepared using hydrothermal method. Cell culture study and In vivo assessments on C57BL/6 mice containing melanoma cancer cells was performed. Results showed that CQD size slightly enhanced from 24.55 nm to 42.67 nm after ICG loading. Detection of reactive oxygen species (ROS) demonstrated that CQD improved ICG photo-stability and ROS generation capacity upon laser irradiation. Cell culture study illustrated that ICG@CQD could decrease survival rate of melanoma cancer cells of B16F10 cell line from 48% for pure ICG to 28% for ICG@CQD. Confocal microscopy images approved more cellular uptake and more qualified cell imaging ability of ICG@CQD. In vivo assessments displayed obvious inhibitory effect of tumor growth for ICG@CQD in comparison to free ICG on the C57BL/6 mice. In vivo fluorescence images confirmed that ICG@CQD accumulates remarkably more than free ICG in tumor region. Finally, ICG@CQD was proposed as an innovative nanocarrier for PDT and diagnosis. [ABSTRACT FROM AUTHOR]

We have adopted a novel CeO2/Bi2MoO6/g-C3N4-based ternary nanocomposite that was synthesized via hydrothermal technique. The physiochemical characterization of as-prepared samples was examined through various analytical techniques such as X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy TEM, photoluminescent spectra (PL), X-ray photoelectron spectroscopy (XPS), Brunauer–Emmett–Teller (BET), and ultraviolet diffuse reflectance spectroscopy (UV-DRS) technique. In addition, the photocatalytic performance was carried out by degradation of Rhodamine B dye under visible light irradiation using this nanocatalyst. The ternary nanocomposite achieved 94% of the degradation efficiency within 100 min which is higher than the pristine and binary composites under the predetermined condition pH = 7, Rhodamine B dye = 5 mg/L, and catalyst concentration = 150 mg/L. The experimental synergetic effect of CeO2/Bi2MoO6/g-C3N4 ternary nanocomposite has been ascribed to the interfacial charge carrier migration between CeO2, Bi2MoO6, and g-C3N4. The optical absorption range of CeO2/Bi2MoO6/g-C3N4 ternary nanocomposite was enhanced, and the band gap was reduced up to 2.2 eV. In addition, scavenger trapping experiment proves that the super oxide anions (O2−.) and photogenerated holes are the major active species. The reusability and stability experiment proved the CeO2/Bi2MoO6/g-C3N4 ternary nanocomposite keeps good durability during the photocatalytic degradation process after the five successive cycles. Furthermore, based on the results, the charge carrier transfer photocatalytic mechanism was also discussed. This CeO2/Bi2MoO6/g-C3N4 ternary nanocomposite may offer the cheapest material and extend the great opportunity for clean and environmental remediation approach under the visible light irradiation. [ABSTRACT FROM AUTHOR]

Organic photovoltaics (OPVs) show great promise for both outdoor and indoor applications. However, there remains a lack of understanding around the stability of OPVs, particularly for indoor applications. In this work, the photostability of the poly[(thiophene)‐alt‐(6,7‐difluoro‐2‐(2‐hexyldecyloxy)quinoxaline)]:2,2′‐((2Z,2′Z)‐((4,4,9,9‐tetrahexyl‐4,9‐dihydro‐s‐indaceno[1,2‐b:5,6‐b′]dithiophene‐2,7‐diyl)bis(methanylylidene))bis(3‐oxo‐2,3‐dihydro‐1H‐indene‐2,1‐diylidene))dimalononitrile blend is investigated for both outdoor and indoor applications. Photostability is found to vary drastically with illumination intensity. Devices under high‐intensity white light‐emitting diode (LED) illumination, with their short‐circuit current density (JSC) matching JSC–EQE for AM1.5 G illumination, lose 42% of their initial performance after 30 days of illumination. Contrastingly, after almost 47 days of illumination devices under 1000 lux white LED illumination show no loss in performance. The poor photostability under 1 sun illumination is linked to the poor photostability of IDIC. Through Raman spectroscopy and mass spectrometry, IDIC is found to suffer from photoisomerization, which detrimentally impacts light absorption and carrier extraction. In this work, it is highlighted that under low light levels, the requirement of intrinsic material photostability may be less stringent. [ABSTRACT FROM AUTHOR]

The photosensitive pharmaceutical ingredient moxifloxacin hydrochloride degrades during storage under the influence of external factors, such as elevated temperature and ultraviolet and visible light irradiation, resulting in a decrease in the concentration of the active substance. To increase its resistance to these external factors, moxifloxacin hydrochloride was encapsulated in halloysite nanotubes. The aim of this study was to determine the level of degradation of moxifloxacin hydrochloride in its native and encapsulated states under the influence of temperature and ultraviolet and visible light irradiation. Encapsulation was carried out by the vacuum method and confirmed by TEM microscopy. The residual content of the photosensitive pharmaceutical ingredient after degradation was monitored by high-performance liquid chromatography of a model solution with an initial concentration of 2 mg/ml, prepared from samples of native and encapsulated moxifloxacin hydrochloride previously tested under the influence of temperature and light irradiation. Encapsulated moxifloxacin hydrochloride showed increased resistance to degradation caused by visible light irradiation at 200 watt-hours/m² (by 10.9%); resistance to degradation was increased by 13.4% and 14% under test conditions during 24 hours of ultraviolet light irradiation and thermostating at a temperature of 60°C, respectively, compared to non-encapsulated moxifloxacin hydrochloride. [ABSTRACT FROM AUTHOR]

Organic-inorganic hybrids are next-generation materials for use in high-performance optoelectronic devices owing to their adaptabilities in terms of design and properties. This article reviews the application of hybrid materials and layers in several widely used optoelectronic devices, i.e., light amplification by stimulated emission of radiation (LASER), solar cells, and light-emitting diodes (LEDs). The effects of the incorporation of inorganic particles on photostability and optical gain are analyzed in the first section with reference to dye and perovskite lasers. Second, the strategies used in blending inorganic nanostructures into organic solar cells and bulk heterojunctions are analyzed. The use of various organic layers as electron- and hole-transport materials in Si heterojunction solar cells is reviewed in detail. Finally, the benefits of the presence of organic components in quantum-dot- and perovskite-based LEDs are derived from the analysis. The integration of organic and inorganic components with optimal interfaces and morphologies is a challenge in developing hybrid materials with improved efficiencies. [ABSTRACT FROM AUTHOR]

Novel push–pull dicyanomethylenedihydrofuran(DCDHF)-based chromophores bearing 6-hydroxyl-2,5,7,8-tetramethylchroman-2-carboxylic acid (HTCX) group were synthesized to function as an antioxidant moiety. The preparation of phenylvinyl-bridged DCDHF chromophores with a hydroxyl functional group to be attached HTCX. Due to intramolecular charge transfer (ICT), HTCX-containing DCDHF chromophores showed a distinct solvatochromism in a range of organic solvents. The molecular structures of the prepared HTCX-bearing DCDHF fluorophores were verified by 1H/13C NMR and FTIR spectroscopic analyses. The emission spectra demonstrated dramatic enhancement in the photostability of the prepared fluorophores. Though, the synthesized HTCX/LSHA(Light Stabilizer Hindered Amine)-DCDHF-based hybrids were studied to evaluated antimicrobial efficiency. HTCX-based hybrid DCDHF-8 revealed sensible activity towards (+ve) Gram and (-ve) Gram bacterial strains, and LSHA-based hybrid DCDHF-15 demonstrated good antibacterial effectiveness against B. cereus (+ve gram) and K. pneumoniae (-ve gram) bactria, comparative to Ampicillin reference. Moreover, the theoretical molecular docking stimulation was realistic to sight see their binding connections towards (PDB-1LNZ).

Abstract Background Quantum Dots (QDs) are fluorescent nanoparticles with exceptional optical and optoelectronic properties, finding widespread utility in diverse industrial applications. Presently, chemically synthesized QDs are employed in solar cells, bioimaging, and various technological domains. However, many applications demand QDs with prolonged lifespans under conditions of high-energy radiation. Over the past decade, microbial biosynthesis of nanomaterials has emerged as a sustainable and cost-effective process. In this context, the utilization of extremophile microorganisms for synthesizing QDs with unique properties has recently been reported. Results In this study, UV-resistant bacteria were isolated from one of the most extreme environments in Antarctica, Union Glacier at the Ellsworth Mountains. Bacterial isolates, identified through 16 S sequencing, belong to the genera Rhodococcus, Pseudarthrobacter, and Arthrobacter. Notably, Rhodococcus sp. (EXRC-4 A-4), Pseudarthrobacter sp. (RC-2-3), and Arthrobacter sp. (EH-1B-1) tolerate UV-C radiation doses ≥ 120 J/m². Isolated UV-resistant bacteria biosynthesized CdS QDs with fluorescence intensities 4 to 8 times higher than those biosynthesized by E. coli, a mesophilic organism tolerating low doses of UV radiation. Transmission electron microscopy (TEM) analysis determined QD sizes ranging from 6 to 23 nm, and Fourier-transform infrared (FTIR) analysis demonstrated the presence of biomolecules. QDs produced by UV-resistant Antarctic bacteria exhibit high photostability after exposure to UV-B radiation, particularly in comparison to those biosynthesized by E. coli. Interestingly, red fluorescence-emitting QDs biosynthesized by Rhodococcus sp. (EXRC-4 A-4) and Arthrobacter sp. (EH-1B-1) increased their fluorescence emission after irradiation. Analysis of methylene blue degradation after exposure to irradiated QDs biosynthesized by UV-resistant bacteria, indicates that the QDs transfer their electrons to O2 for the formation of reactive oxygen species (ROS) at different levels. Conclusions UV-resistant Antarctic bacteria represent a novel alternative for the sustainable generation of nanostructures with increased radiation tolerance—two characteristics favoring their potential application in technologies requiring continuous exposure to high-energy radiation. Graphical abstract

Leather tanning involves several processes of converting putrescible hide to stable leather resistant to harsh environmental conditions. Severe conditions such as high temperatures and UV radiation, when exposed to the leather materials, cause degradation and decrease physical, chemical, and structural properties. The effect of gamma irradiation on viscoelastic properties and stability of tanned leather against thermal and photodegradation was studied using the Dynamic Mechanical Analysis (DMA) technique. The thermal stability of chrome and mimosa-tanned leather was inferred from the peak of storage modulus graphs. Gamma irradiation of samples with low doses increased the storage modulus of chrome and mimosa-tanned leathers. Doses up to 20 kGy decreased the stability of thermally aged chrome-tanned leather. However, for mimosa-tanned, there was an increase at higher doses as a result of gamma irradiation inducing additional bonds that enhance the stability of the tanned leather. Nevertheless, there is a variation in the stability of chrome-tanned leather at different doses of irradiation.

Single‐molecule localization microscopy has proved promising to unravel the dynamics and molecular architecture of thin biological samples down to nanoscales. For applications in complex, thick biological tissues shifting single‐particle emission wavelengths to the shortwave infrared (SWIR also called NIR II) region between 900 to 2100 nm, where biological tissues are more transparent is key. To date, mainly single‐walled carbon nanotubes (SWCNTs) enable such applications, but they are inherently 1D objects. Here, 0D ultra‐small luminescent gold nanoclusters (AuNCs, <3 nm) and ≈25 nm AuNC‐loaded‐polymeric particles that can be detected at the single‐particle level in the SWIR are presented. Thanks to high brightness and excellent photostability, it is shown that the dynamics of the spherical polymeric particles can be followed at the single‐particle level in solution at video rates for minutes. We compared single particle tracking of AuNC‐loaded‐polymeric particles with that of SWCNT diffusing in agarose gels demonstrating the specificity and complementarity of diffusion properties of these SWIR‐emitting nano‐objects when exploring a complex environment. This extends the library of photostable SWIR emitting nanomaterials to 0D nano‐objects of variable size for single‐molecule localization microscopy in the second biological window, opening unprecedented possibilities for mapping the structure and dynamics of complex biological systems. [ABSTRACT FROM AUTHOR]

Designing plasmonic nanoparticles for biomedical photoacoustic (PA) imaging involves tailoring material properties at the nanometer scale. A key in developing plasmonic PA contrast nanoagents is to engineer their enhanced optical responses in the near‐infrared wavelength range, as well as heat transfer properties and photostability. This study introduces anisotropic plasmonic nanosphere aggregates with close interparticle proximity as photostable and efficient contrast agents for PA imaging. Silver (Ag) is particularly attractive because it has the strongest optical response and highest heat conductivity among plasmonic metals. The results demonstrate that close interparticle proximity in silver nanoaggregates (AgNAs), spatially confined within a polymer shell layer, leads to blackbody‐like optical absorption, resulting in robust PA signals through efficient pulsed heat generation and transfer. Additionally, the AgNAs exhibit a high photodamage threshold highlighting their potential to outperform conventional plasmonic contrast agents for high‐contrast PA imaging over multiple imaging sessions. Furthermore, the capability of the AgNAs are demonstrated for molecular PA cancer imaging in vivo by incorporating a tumor‐targeting peptide moiety. [ABSTRACT FROM AUTHOR]

We report a family of donor‐acceptor thermally activated delayed fluorescent (TADF) compounds based on derivatives of DMAC‐TRZ, that are strongly photoreducing. Both Eox and thus E*ox could be tuned via substitution of the DMAC donor with a Hammett series of p‐substituted phenyl moieties while Ered remained effectively constant. These compounds were assessed in the photoinduced dehalogenation of aryl halides, and analogues bearing electron withdrawing groups were found to produce the highest yields. Substrates of up to Ered=−2.72 V could be dehalogenated at low PC loading (1 mol %) and under air, conditions much milder than previously reported for this reaction. Spectroscopic and chemical studies demonstrate that all PCs, including literature reference PCs, photodegrade, and that it is these photodegradation products that are responsible for the reactivity. [ABSTRACT FROM AUTHOR]

The biological activities and related mechanisms of curcumin, a major polyphenolic compound in turmeric, the rhizome of Curcuma longa, have been extensively investigated. Due to its poor solubility in water, the analysis of curcumin's biological activities is limited in most aqueous experimental systems. In the present study, the effects of polyvinyl alcohol (PVA), a dietary-compatible vehicle, on the solubility, stability, cellular uptake, and bioactivities of curcumin were investigated. Curcumin solubility was improved significantly by PVA; the color intensity of curcumin aqueous solution in the presence of PVA increased concentration-dependently with its peak shift to a shorter wavelength. Improved suspension stability and photostability of curcumin in an aqueous solution were also observed in the presence of PVA, even at 62.5 μg/mL. The scavenging activities of curcumin against DPPH, ABTS, AAPH radicals, and nitric oxide were enhanced significantly in the presence of PVA. PVA at 250 μg/mL also significantly enhanced the cytotoxic activity of curcumin against both HCT 116 colon cancer and INT 407 (HeLa-derived) embryonic intestinal cells by reducing the IC50 from 16 to 11 μM and 25 to 15 μM, respectively. PVA improved the cellular uptake of curcumin in a concentration-dependent manner in INT 407 cells; it increased the cellular levels more effectively at lower curcumin treatment concentrations. The present results indicate that PVA improves the solubility and stability of curcumin, and changes in these chemical behaviors of curcumin in aqueous systems by PVA could enhance the bioavailability and pharmacological efficacy of curcumin. [ABSTRACT FROM AUTHOR]

In this study, photostability and photodynamic antimicrobial performance of dye extracts from Hibiscus sabdariffa (HS) calyces, Sorghum bicolor (SB) leaf sheaths, Lawsonia inermis (LI) leaves and Curcuma longa (CL) roots were investigated in Acetate-HCl (AH) Buffer (pH 4.6), Tris Base-HCl (TBH) Buffer (pH 8.6), distilled water (dH2O), and Phosphate Buffer Saline (PBS, pH 7.2) using Bacillus subtilis as model for gram positive bacteria, Escherichia coli as model for gram negative bacteria, phage MS2 as model for non-envelope viruses and phage phi6 as model for envelope viruses including SARS CoV-2 which is the causative agent of COVID-19. Our results showed that the photostability of the dye extracts is in the decreasing order of LI > CL > SB > HS. The dye extract-HS is photostable in dH2O but bleaches in buffers—AH, TBH and PBS. The rate of bleaching is higher in AH compared to in TBH and PBS. The bleaching and buffers affected the photodynamic and non-photodynamic antimicrobial activity of the dye extracts. The photodynamic antibacterial activity of the dye extracts is in the decreasing order of CL > HS > LI > SB while the non-photodynamic antibacterial activity is in the decreasing order of LI > CL > HS > SB. The non-photodynamic antiviral activity pattern observed is the same as that of non-photodynamic antibacterial activity observed. However, the photodynamic antiviral activity of the dye extracts is in the decreasing order of CL > LI > HS > SB. Given their performance, the dye extracts maybe mostly suitable for environmental applications including fresh produce and food disinfection, sanitation of hands and contact surfaces where water can serve as diluent for the extracts and the microenvironment is free of salts. [ABSTRACT FROM AUTHOR]

Fast-growing wood generally has drawbacks such as soft texture, low strength, and poor photostability, which greatly limits its use value and application scope. In this article, nano-Al2O3/ZnO modified wood was prepared by magnetron sputtering with fast-growing poplar as the substrate. The results showed that when Al2O3 and composite films were deposited on fast-growing wood, their load-displacement curves were significantly shifted to the left, meaning that the deformation resistance of wood was enhanced. The maximum pressure depth of nano-Al2O3/ZnO/wood was 246.3 nm, a decrease of 80.1% from CTRL wood. The average elastic modulus was 4.683 GPa, an increase of 20.48 times; the average hardness was 0.731 GPa, an increase of 28.41 times. After 222 h ultraviolet irradiation, total color difference values ($\Delta E^{\rm \ast }$ Δ E ∗ ) of nano-ZnO/wood, nano-Al2O3/ZnO/wood, and nano-ZnO/Al2O3/wood were 4.31, 4.73, and 5.25, respectively, which were more than 70% lower than that of the CTRL wood (19.76). Continuous and uniform nanofilms were observed on the surface, and the highest weight percentage of Al and Zn elements reached 9.38% and 60.21% respectively. It was concluded that the nano-Al2O3/ZnO/wood prepared by magnetron sputtering resulted in good Young's modulus, hardness, and photostability, achieving multi-function improvement of fast-growing wood. [ABSTRACT FROM AUTHOR]

Background: Quantum Dots (QDs) are fluorescent nanoparticles with exceptional optical and optoelectronic properties, finding widespread utility in diverse industrial applications. Presently, chemically synthesized QDs are employed in solar cells, bioimaging, and various technological domains. However, many applications demand QDs with prolonged lifespans under conditions of high-energy radiation. Over the past decade, microbial biosynthesis of nanomaterials has emerged as a sustainable and cost-effective process. In this context, the utilization of extremophile microorganisms for synthesizing QDs with unique properties has recently been reported. Results: In this study, UV-resistant bacteria were isolated from one of the most extreme environments in Antarctica, Union Glacier at the Ellsworth Mountains. Bacterial isolates, identified through 16 S sequencing, belong to the genera Rhodococcus, Pseudarthrobacter, and Arthrobacter. Notably, Rhodococcus sp. (EXRC-4 A-4), Pseudarthrobacter sp. (RC-2-3), and Arthrobacter sp. (EH-1B-1) tolerate UV-C radiation doses ≥ 120 J/m². Isolated UV-resistant bacteria biosynthesized CdS QDs with fluorescence intensities 4 to 8 times higher than those biosynthesized by E. coli, a mesophilic organism tolerating low doses of UV radiation. Transmission electron microscopy (TEM) analysis determined QD sizes ranging from 6 to 23 nm, and Fourier-transform infrared (FTIR) analysis demonstrated the presence of biomolecules. QDs produced by UV-resistant Antarctic bacteria exhibit high photostability after exposure to UV-B radiation, particularly in comparison to those biosynthesized by E. coli. Interestingly, red fluorescence-emitting QDs biosynthesized by Rhodococcus sp. (EXRC-4 A-4) and Arthrobacter sp. (EH-1B-1) increased their fluorescence emission after irradiation. Analysis of methylene blue degradation after exposure to irradiated QDs biosynthesized by UV-resistant bacteria, indicates that the QDs transfer their electrons to O2 for the formation of reactive oxygen species (ROS) at different levels. Conclusions: UV-resistant Antarctic bacteria represent a novel alternative for the sustainable generation of nanostructures with increased radiation tolerance—two characteristics favoring their potential application in technologies requiring continuous exposure to high-energy radiation. [ABSTRACT FROM AUTHOR]

Although organic solar cells (OSCs) have received increasing attention because of their high device efficiencies, the fundamental mechanism governing their photostability remains elusive. Herein, the effect of the luminescence stability of the acceptor components on the burn‐in voltage loss of binary and ternary OSCs is demonstrated. A systematic characterization reveals that the acceptor component experiences an abnormal decrease in luminescence under photoaging—specifically, photoinduced luminescence quenching—because of a photoinduced conformational change. This phenomenon increases nonradiative recombination in blends and thus causes a substantial nonradiative voltage loss of OSCs. Moreover, an introduction of a third component with high luminescence stability can effectively reduce the burn‐in voltage loss of OSCs. A composition‐dependent photostability study of the resultant ternary OSCs reveals that the reduction in the burn‐in voltage loss of OSCs is mainly driven by the third component distributed in the mixed phase; high luminescence stability of this component effectively prevents the increase in nonradiative voltage loss by photoaging. The results suggest that improving the luminescence stability of the acceptor components can be an effective method for highly stable photovoltaics with greatly reduced burn‐in voltage loss. [ABSTRACT FROM AUTHOR]

UV light-induced photodegradation of the organic–inorganic hybrid (OIH) Ruddlesden–Popper (RP) perovskite nanoplates (NPls) is a crucial bottleneck for optoelectronic application in the future. Continuous UV exposure triggers the deprotonation of the spacer as well as the A-site cation (CH3NH3+), ultimately leading to lattice collapse. To combat this photoinstability, we introduce a surface modification of colloidal OIH RP NPls, (OAm)2(CH3NH3PbI3)2PbI4 (n = 3) (OAm stands for oleylammonium cation) by 4-fluorobenzylammonium iodide (4FBAI). In ambient conditions, conventional NPls deteriorate within 80 min of UV exposure, whereas the 4FBAI-modified NPls exhibit remarkable endurance, maintaining structural integrity for 12 h with only a 11% reduction in the initial photoluminescence (PL). Interestingly, benzylammonium iodide (BAI) and 4-methoxybenzylammonium iodide (4OBAI)-treated NPl fail to provide similar photostability, thus signifying the importance of the fluorine atom. The fluorine atom enhances the positive charge density of the ammonium ion and facilitates faster deprotonation compared to parental ammonium ions (here, OAm+ and CH3NH3+) under UV exposure. This ensures the survival of the parent nanoplate structure. Along with the photostability enhancement, the PL quantum yield of the treated NPl also increases to 50 ± 2 from 35 ± 2%. This research not only addresses the pressing photostability issue of RP NPl stability but also illuminates the pivotal role of specific chemical modifications, such as fluorine atom incorporation, for the fabrication of UV-stable perovskite devices in the future. [ABSTRACT FROM AUTHOR]

[Display omitted] A systematic study of the UV light-induced degradation of a series of structurally similar conjugated polymers revealed important relationships between the molecular structure of the used building blocks and photostability of the resulting materials. These findings form a set of important guidelines for future rational design of new absorber materials for efficient and stable organic solar cells. [ABSTRACT FROM AUTHOR]

High‐resolution spatio‐temporal monitoring of the cell membrane lipid order provides visual insights into the complex and sophisticated systems that control cellular physiological functions. Solvatochromic fluorescent probes are highly promising noninvasive visualization tools for identifying the ordering of the microenvironment of plasma membrane microdomains. However, conventional probes, although capable of structural analysis, lack the necessary long‐term photostability required for live imaging at the cellular level. Here, an ultra‐high‐light‐resistant solvatochromic fluorescence probe, 2‐N,N‐diethylamino‐7‐(4‐methoxycarbonylphenyl)‐9,9‐dimethylfluorene (FπCM) is reported, which enables live lipid order imaging of cell division. This probe and its derivatives exhibit sufficient fluorescence wavelengths, brightness, polarity responsiveness, low phototoxicity, and remarkable photostability under physiological conditions compared to conventional solvatochromic probes. Therefore, these probes have the potential to overcome the limitations of fluorescence microscopy, particularly those associated with photobleaching. FπCM probes can serve as valuable tools for elucidating mechanisms of cellular processes at the bio‐membrane level. [ABSTRACT FROM AUTHOR]