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The development of efficient, stable, and sustainably fabricated photocatalysts for solar-driven hydrogen evolution remains a critical challenge in the field. Herein, we report a novel green coprecipitation strategy to synthesize calcium-doped zinc oxide (Ca-ZnO) nanosheets, utilizing cactus juice as a natural, multifunctional medium for the coprecipitation process. This method enables the in situ, tunable incorporation of 3–7% Ca²⁺ ions into the wurtzite ZnO lattice without the use of harsh chemical reagents. Comprehensive characterization confirms that Ca²⁺ substitutionally replaces Zn²⁺, which preserves the intrinsic crystal structure of ZnO well while inducing the formation of uniform nanosheet morphology. This doping strategy effectively modulates the electronic band structure, progressively narrowing the bandgap from 3.19 eV to 2.90 eV and significantly enhancing visible-light absorption. Crucially, the incorporation of Ca²⁺ also generates oxygen vacancies, which serve as efficient electron traps to suppress photogenerated charge carrier recombination. The optimized 5%Ca-ZnO photocatalyst demonstrates a favorable hydrogen evolution rate of 889 μmol·g⁻¹·h⁻¹ under full-spectrum irradiation, with stability, retaining 94.8% of its activity after four cycles. This work not only provides a high-performance material but also establishes a generalizable, sustainable paradigm for the design of advanced semiconductor photocatalysts. Full article

Photoresponsive hydrogen-bonded azo-macrocycles capable of selectively recognizing lithium cation were constructed by reversing the amide–azobenzene connectivity, which redistributes electron density and preorganizes four carbonyl oxygen donors into a smaller, more convergent cavity. Compared with a connectivity-isomeric reference macrocycle, the new receptor displays a pronounced preference for Li⁺, in which complexation with LiClO₄ shows a slow exchange on the ¹H NMR timescale and an association constant (K_a) exceeding 10⁴ M⁻¹, whereas the reference binds Li⁺ weakly (<5 M⁻¹). In contrast, both hosts exhibit only modest binding toward Na⁺ (10²~10³ M⁻¹) and fast exchange, consistent with size/geometry matching of the compressed cavity to Li⁺. The newly designed azo-macrocycles reveal a highly selective recognition of Li⁺ thanks to the more evenly arrayed four amide oxygens enclosing a cavity of small dimension. Notably, E/Z photoisomerization of macrocycle switches the binding regime, enabling reversibly light-triggered Li⁺ binding under UV irradiation and recapture under visible light. This work establishes a new photoresponsive receptor based on H-bonded azo-macrocycles for photoswitchable recognition of Li⁺. Full article

Metal–organic frameworks (MOFs) are unique microporous materials being explored for a wide range of applications. Their porosity and high surface areas can readily be exploited for guest–host interactions, separations, and photochemical catalysis, but many suffer from poor charge separation and fast electron–hole recombination. Introducing structural defects, such as missing linkers or metal nodes, can create unsaturated metal sites and alter band structure, conductivity, and light absorption, improving photocatalytic performance. UiO-66-NH₂ and MIL-125-NH₂ are water-stable, visible-light-absorbing MOFs well suited for photocatalytic degradation of organic dyes. In this work, the influence of defect engineering on photocatalytic properties of MOFs was investigated using formic and acetic acid modulators with UiO-66-NH₂ and variable temperature with MIL-125-NH₂ during synthesis. The resulting materials were characterized by XRD, FTIR and SEM/EDS. Defect states were tracked using N₂ adsorption/BET analysis and UV–Vis spectroscopy. Photocatalytic activity was evaluated by monitoring Rhodamine B (RhB) degradation in aqueous solution under simulated solar irradiation. It was found that increased temperature beyond 120 °C during synthesis promotes mesopore formation and decreases the bandgap in MIL-125-NH₂, resulting in a more photoactive material. Defective MIL-125-NH₂ synthesized at 150 °C showed the most defects and proved to be the best photocatalyst investigated in this study. Formic acid modulation in UiO-66-NH₂ generated smaller crystallites that slightly increased the bandgap; however, the surface area decreased proportionally with the amount of formic acid used. The decreased surface area and observed enhancement in photocatalytic degradation of RhB suggest that formic acid introduces defects into the UiO-66-NH₂ framework that enhance photocatalytic properties. UiO-66-NH₂ treated with acetic acid resulted in larger crystals, increased bandgaps, and increased surface areas, suggesting that acetic acid simply modulates growth rather than imparting defects to the framework. Full article

Age-related muscle decline is associated with impaired mitochondrial bioenergetics, altered redox signaling, and reduced myogenic capacity, yet how photobiomodulation (PBM) source characteristics shape these processes under replicative aging remains unclear. Here, we investigated source-specific PBM responses in C2C12 myoblasts using a 660 nm light-emitting diode (LED) and an 830 nm near-infrared (NIR) laser across fluence ranges and replicative stages. Single-cell screening performed at passage 25 identified 5 J/cm² as the optimal fluence for both sources, producing biphasic increases in mitochondrial membrane potential and ROS. Population-level assays in young (≤5 passages) and old (≥30 passages) cells revealed divergent downstream outcomes. LED irradiation elicited stronger metabolic activation and ATP production, particularly in aged cells, whereas NIR irradiation robustly enhanced myogenic fusion in both age groups and partially rescued differentiation deficits in aged myoblasts. Bulk ROS increased significantly after PBM independent of source, while extracellular vesicle release displayed age-dependent source sensitivity, with NIR favoring canonical small EV populations in young cells and LED inducing greater particle release in aged cells. Together, these findings demonstrate that PBM engages conserved mitochondrial signaling while source-specific delivery and wavelength differentially direct metabolic, paracrine, and myogenic outputs under replicative aging conditions. Full article

Light availability is a key environmental factor influencing plant functional traits and ecological strategies. To investigate how natural populations of Iris pumila respond to contrasting irradiance, we conducted an in situ reciprocal transplant experiment using clonal genotypes from two natural populations, each originating from an open dune and a shaded forest habitat. Leaves collected from each of the replanted and transplanted genotypes were analyzed for structural (specific leaf area—SLA, leaf dry matter content—LDMC), physiological (specific leaf water content—SLWC, photosynthetic pigments) and biochemical (peroxidase—POD, glutathione reductase—GR, phenolics and anthocyanins) traits. Shade-grown individuals developed thinner leaves with higher SLA and chlorophyll content, enhancing light-harvesting efficiency, whereas sun-exposed plants exhibited greater LDMC, increased POD and GR activities and higher anthocyanin levels—traits consistent with enhanced photoprotection under high irradiance. All genotypes exhibited pronounced plasticity to light intensity, with habitat exerting a stronger influence on trait expression than population origin. To evaluate oxidative balance, we proposed the ODAC index (Oxidative Damage to Antioxidant Capacity), which integrates lipid peroxidation with antioxidant capacity. ODAC values revealed consistent population-level differences, with higher values in Dune genotypes across habitats, indicating a constitutively elevated oxidative load relative to antioxidant protection and suggesting differentiation in redox regulation between populations. Overall, leaf trait variation in I. pumila appears to be primarily driven by plastic responses to light conditions, while differentiation in oxidative physiology contributes to functional divergence between populations. Full article

Photodynamic therapy (PDT) is a promising cancer treatment employing photo-induced reactive oxygen species (ROS) generation by a photosensitizer (PS). Titanium dioxide (TiO₂) is a potential PS due to its superb photocatalytic features and biocompatibility. However, its clinical potential is restricted by its predominant ultraviolet (UV) absorption. To address this limitation, this work introduces TiO₂/carbon dots (CDs) nanohybrid materials for improving the photophysical properties of TiO₂ and its photodynamic performance. TiO₂ and CDs were synthesized through wet chemical and hydrothermal techniques, and subsequently combined via a facile ex situ solvothermal process to produce hybrid materials containing 1–50% w/w CDs. The materials were characterized using XRD, Raman, TEM, FT-IR, zeta potential, TGA, UV-Vis and PL. PDT studies on A431 skin cancer cells indicated improved photosensitizing ability of TiO₂/CDs, with TiO₂/CDs (10%) inducing 47% cell toxicity, versus 20% for TiO₂ after 10 min of red-light irradiation (661 nm, 18 mW/cm², 12.96 J/cm²). Intracellular localization studies revealed enhanced cellular uptake of TiO₂/CDs (10%), compared with TiO₂. In vitro studies on 3T3 healthy fibroblasts confirmed PSs’ safety both with and without light. Overall, this study elucidates the key role of CDs in the photophysical and photodynamic behavior of TiO₂-based systems, providing design guidelines for the next-generation inorganic PSs. Full article

Organic dye-, pharmaceutical-, and heavy metal-contaminated water are emerging environmental issues, and thus there is a requirement for the development of efficient and sustainable purification methods. Semiconductor (SmC) material-based photocatalysis using TiO₂ and Fe₂O₃ nanostructures is considered a promising field for pollutant degradation due to its chemical stability, nontoxicity, and ability to perform photocatalytic degradation using light irradiation. Understanding the thermal, optical, and charge transport properties governing their photocatalytic activity requires advanced characterisation methods. In this context, photothermal (PT) techniques provide powerful tools for probing non-radiative processes and energy transport in photocatalytic materials. The photocatalytic activity of these materials strongly depends on their structural, optical, thermal, and electronic properties. These properties can be enhanced through several modification strategies, including metal and non-metal doping (e.g., C, N, Cu, Ag, Au), surface modification, forming a complex with SiO₂, and the formation of Fe₂O₃–TiO₂ heterostructure nanocomposites. In this review, a comprehensive overview is provided of TiO₂ and Fe₂O₃-based nanocomposites with a specific focus on characterisation techniques for photothermal characterisation techniques, including thermal lens spectroscopy (TLS), beam deflection spectrometry (BDS), and photoacoustic spectroscopy (PAS), for determining thermal diffusivity, thermal conductivity, bandgap energy, carrier lifetime, surface roughness, porosity, etc., which are related to photocatalytic activity. The properties of these nanocomposites are correlated with photocatalytic activity for pollutant degradation using these nanocomposites. The challenges faced while using these nanocomposites for pollutant degradation are also discussed, along with future prospects for designing efficient photocatalysts for water purification applications. Full article

In search of a non-surgical alternative for male animal sterilization, this study investigated the use of gold-coated maghemite nanoparticles (γ-Fe₂O₃@Au) functionalized with citrate to produce testicular photohyperthermia (PHT). Wistar rats received an intratesticular injection of the fluid containing the nanoparticles (150 µL/testicle) followed by testicular irradiation with an LED light (808 nm). Testicular temperature was maintained at ~45 °C for 15 min. The results demonstrated a significant reduction in testicular volume and weight and sperm motility and normal morphology in PHT-treated animals, together with histopathological degeneration of seminiferous tubules. No treatment-related side effects or signs of systemic toxicity were observed. The biodistribution of the gold (Au) and iron (Fe) from the nanoparticles showed that the testes were the primary site of nanoparticle accumulation until day 56 post-treatment with possible renal excretion of Au. These findings support the prospect of testicular PHT mediated by γ-Fe₂O₃@Au nanoparticles as a neutering method for male animals. Full article

Field trials were conducted to define several parameters associated with adding LEDs to monitoring traps for codling moth (CM), Cydia pomonella (L.), using both a sex pheromone lure (PH1X) and a non-pheromone lure (CM4K). Traps with LEDs emitting at a peak of 395 nm with 1000–2000 mW/m² were the most effective. Lights with greater intensities caught similar numbers of CMs and significantly more non-targets. Adding the UV-A lights did not increase moth catches early in the season with either the PH1X or CM4K lures. However, UV-A LEDs, when used with these two lures, significantly increased total moth catches 7- and 3-fold in July and August, respectively. The addition of the UV-A LEDs allowed CM4K-baited traps to perform significantly better in previously limiting situations, such as in weedy orchards, and in pear relative to apple. Distance from the light source is a key factor affecting light energy. Irradiance dropped >90% at 15 cm, which is the distance from the lure to the entrance of a standard delta trap. A smaller trap (7.5 cm radius) had a 4-fold greater irradiance at its entrance and caught greater numbers of non-targets but not CMs than delta traps without LEDs. Full article

Phenazine derivatives are promising metal-free chromophores with strong redox and photophysical properties, yet their use in photocatalytic hydrogenation remains limited. Here, we report a homogeneous phenazine-based system for the visible-light-driven hydrogenation of nitroarenes under mild conditions. Using nitrobenzene as a model substrate and triethanolamine as a sacrificial hydrogen source, the photocatalyst achieved aniline yields of up to 81% after 12 h of irradiation at 390 nm. Systematic variation in reaction parameters revealed that catalyst structure, solvent, and light wavelength strongly influence performance. Kinetic analysis indicated that prolonged irradiation reduces overall yield due to the reconversion of reactive intermediates. The system exhibited higher efficiency toward nitroarenes bearing electron-withdrawing groups, while aliphatic nitro compounds underwent only partial reduction. Mechanistic studies using UV–Vis, fluorescence, and EPR spectroscopy confirmed the formation of persistent radical species and supported a stepwise electron and proton transfer mechanism. This work showcases the potential of phenazine-based photocatalysts as metal-free platforms for nitroarene reduction under visible light. Full article

The widespread presence of antibiotic residues in aquatic environments poses severe ecological risks. While photocatalytic oxidation offers a promising, eco-friendly remediation technology, developing stable and high-efficiency photocatalysts remains a significant challenge. This study investigates the synthesis of Bi₂O₃/TiO₂ heterojunction with tailored morphological structures to enhance the degradation of tetracycline (TC). A series of Bi₂O₃/TiO₂ photocatalysts were prepared via a solvothermal method using mixed alcohol solvents (ethylene glycol and ethanol) to regulate morphology. Comprehensive characterization was performed using XRD, BET, TEM, XPS, UV-Vis, and PL spectroscopy. Photocatalytic activity was evaluated by monitoring TC removal efficiency under light irradiation. The optimized catalyst of BT5-EG3 (n(Bi)/n(Ti) = 0.05; V(EG):V(ethanol) = 1:3) achieved the highest TC conversion of 93.9% within 120 min. This superior performance is attributed to a large specific surface area, abundant lattice oxygen, and a narrowed band gap of 2.52 eV, which significantly promoted the spatial separation of photogenerated charge carriers and suppressed their ultrafast recombination. The reaction followed pseudo-first-order kinetics, and the catalyst demonstrated excellent stability, providing a robust strategy for treating antibiotic-polluted water. Full article

Daily exposure to blue light emitted by digital devices has raised concerns about oxidative stress-mediated damage to the ocular surface. Despite growing interest, validated in vitro models to study blue light-induced oxidative stress in corneal epithelial cells remain limited. A reproducible in vitro method was developed using rabbit corneal epithelial (RCE) cells exposed to blue LED light (405 nm). Irradiation parameters were optimized to induce oxidative stress without causing overt cytotoxicity. Cellular viability, intracellular ROS production, and mitochondrial oxidative stress were assessed. The model was validated using reference antioxidants (ascorbic acid and oleuropein), oleuropein formulated in a drug-in-cyclodextrin-in-liposome system (OLE-DCL), and two commercial ophthalmic formulations applied before or after irradiation. Blue light irradiation at 4.57 W/m² for 30 min significantly increased intracellular and mitochondrial ROS levels while preserving cell viability, indicating sublethal photo-oxidative stress. Ascorbic acid effectively suppressed ROS generation, whereas free oleuropein showed reduced efficacy, likely due to photosensitivity. OLE-DCL significantly enhanced antioxidant activity under irradiation. The model also discriminated between protective and restorative treatment strategies. This study establishes a validated in vitro blue light-induced oxidative stress model for corneal epithelial cells, suitable for screening antioxidant compounds, formulations, and application strategies relevant to ocular surface protection. Full article

CaCO₃/BiO_2−x/CdS (CCO/BO/CS) ternary composite photocatalyst was synthesized via a hydrothermal method combined with chemical precipitation, and its performance in the photocatalytic reduction of hexavalent chromium (Cr(VI)) under visible light was systematically investigated. Compared with pure BiO_2−x, CdS, and binary BiO_2−x/CdS composites, the CCO/BO/CS system exhibited significantly enhanced Cr(VI) reduction activity. Specifically, the CCO/BO/CS (0.75:1:2 wt) composite achieved a Cr(VI) reduction efficiency of 94.53% within 30 min of visible light irradiation—approximately 94.6 times and 6.1 times higher than those of BiO_2−x (1.0%) and CdS (15.52%). Photoelectrochemical and trapping experiments revealed that the enhanced performance stems from improved charge separation, accelerated interfacial electron transfer, and the promotional role of CaCO₃—likely through lattice distortion—rather than direct photocatalytic participation. This study highlights the innovation of incorporating low-cost, eco-friendly calcium carbonate into semiconductor-based photocatalysts to induce lattice distortion for enhanced charge separation, as an effective strategy for improving the reduction efficiency of Cr(VI). Full article

This study investigated the effect of CAD-CAM resin composite thickness on the polymerization behavior of dual-cure resin cements used for endocrown restorations. Three commercially available dual-cure resin cements and one light-cure resin cement (for comparison) were polymerized by light irradiation through CAD-CAM resin composite plates of varying thicknesses (1.5, 3.5, 5.5, 7.5, and 9.5 mm). Transmitted light intensity was measured using an optical spectrometer. Polymerization behavior was evaluated immediately after irradiation and after 24 h of aging using Fourier transform infrared spectroscopy to determine the degree of conversion (DC) and Vickers hardness (VH) testing. Transmitted light intensity decreased logarithmically with increasing composite thickness, with less than 1% of incident light reaching the resin cement at thicknesses ≥ 5.5 mm. For the dual-cure resin cements, DC and VH values significantly decreased when the composite thickness exceeded 5.5 mm. Although DC and VH increased after 24 h due to self-curing, values beneath thicker composites remained lower than those beneath 1.5 mm thick composites. The light-cure resin cement failed to polymerize when the composite thickness exceeded 7.5 mm. These results indicate that CAD-CAM resin composite thickness critically influences resin cement polymerization, highlighting the importance of thickness control in endocrown restorations. Full article

Benzothiophene polymers, as a class of novel organic semiconductor materials, exhibit significant potential in the field of photocatalysis due to their broad light-responsive range and tunable energy level structures. In this study, a benzothiophene-based polymer organic semiconductor (denoted as P42) was integrated with titanium dioxide (TiO₂) via a simple sol–gel method, yielding an organic–inorganic hybrid material. This composite facilitates the modulation of energy level potentials and promotes the effective separation of photogenerated charges, thereby demonstrating remarkable synergistic catalytic performance in the photocatalytic oxidative coupling of benzylamines. By optimizing the ratio of organic to inorganic components and various photocatalytic reaction conditions, the hybrid material 1.7%P42-TiO₂, containing 1.7 wt% of the dithiophene polymer without any metal cocatalysts, exhibited outstanding performance under an air atmosphere and visible light irradiation after 12 h. It achieved a yield of over 88.7% and a selectivity exceeding 89.8% in the synthesis of N-benzoylaniline, significantly surpassing the performance of pure TiO₂ (52.9% yield, 54.9% selectivity) and P42 (54.4% yield, 54.9% selectivity). Structural and photophysical characterizations, including UV–Vis DRS, XRD, SEM, TEM, and EPR, reveal that the enhanced photocatalytic activity originates from broad visible-light absorption, improved charge separation, and well-matched energy levels. Mechanistic investigations suggest a synergistic pathway involving photoinduced hole oxidation and radical-mediated coupling. This work provides valuable insights and a reference for the solar-driven photocatalytic synthesis of nitrogen-containing platform molecules under mild conditions. Full article