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Abstract Metal halide perovskites (MHPs, CsPbX3: X = Cl, Br, I) have advanced the field of optoelectronic devices due to their remarkable light‐emitting capabilities, stemming from the large overlap between their emission and absorption spectra, offering the possibility to reabsorb their own emitted photons. Herein, a straightforward method is reported to confine CsPbBr3 into mesoporous silica films with a chiral nematic structure, allowing the amplification of the photoluminescence (PL). The simple room temperature ligand‐free synthesis allows facile growth of CsPbBr3 in silica photonic films, in which the Bragg peak position can be tuned from the UV to the visible range. The perovskite/silica films demonstrate a remarkable improvement in PL intensity and lifetime compared to the as‐synthesized non‐confined perovskite nanocrystals (NCs) due to the overlap of the Bragg peak position of the chiral nematic photonic films and CsPbBr3 absorption band. Such a PL enhancement stems from the slow photon effect induced at blue and red Bragg peak edges that facilitates the photon recycling of the emitted photons. This innovative approach offers a new way to fabricate highly emissive and long‐lived photoluminescent films at ambient conditions, potentially advancing perovskite utilization in light‐emitting devices.

Abstract Barium phosphate (Ba3(PO4)2) is a class of material that has attracted significant attention thanks to its chemical stability and versatility. However, the use of Ba3(PO4)2 as a photocatalyst is scarcely reported, and its use as a photocatalyst has yet to be reported. Herein, Ba3(PO4)2 nanoflakes synthesis is optimized using sol‐gel and hydrothermal methods. The as‐prepared Ba3(PO4)2 powders are investigated using physicochemical characterizations, including XRD, SEM, EDX, FTIR, DRS, J–t, LSV, Mott‐Schottky, and EIS. In addition, DFT calculations are performed to investigate the band structure. The oxidation capability of the photocatalysts is investigated depending on the synthesis method using rhodamine B (RhB) as a pollutant model. Both Ba3(PO4)2 samples prepared by the sol‐gel and hydrothermal methods display high RhB photodegradation of 79% and 68%, respectively. The Ba3(PO4)2 obtained using the sol‐gel process exhibits much higher stability under light excitation after four regeneration cycles. The photocatalytic oxidation mechanism is proposed based on the active species trapping experiments where O2•‒ is the most reactive species. The finding shows the promising potential of Ba3(PO4)2 photocatalysts and opens the door for further investigation and application in various photocatalytic applications.

Although titanium dioxide (TiO2) has a wide range of potential applications, the photocatalytic performance of TiO2 is limited by both its limited photoresponse range and fast recombination of the photogenerated charge carriers. In this work, the preparation of nitrogen (N)-doped TiO2 accompanied by the introduction of oxygen vacancy (Vo) has been achieved via a facile annealing treatment with urea as the N source. During the annealing treatment, the presence of urea not only realizes the N-doping of TiO2 but also creates Vo in N-doped TiO2 (N-TiO2), which is also suitable for commercial TiO2 (P25). Unexpectedly, the annealing treatment-induced decrease in the specific surface area of N-TiO2 is inhibited by the N-doping and, thus, more active sites are maintained. Therefore, both the N-doping and formation of Vo as well as the increased active sites contribute to the excellent photocatalytic performance of N-TiO2 under visible light irradiation. Our work offers a facile strategy for the preparation of N-TiO2 with Vo via the annealing treatment with urea.

A one‐pot synthesis of plasmonic gold‐modified TiO2 nanocomposites is reported by using glucose reduction of HAuCl4 in presence of titanium tetraisopropoxide. The resulting nanocomposites are characterized by thermal‐gravimetric analyses, X‐ray diffraction combined with X‐ray fluorescence and photoelectron spectroscopies. A binary system of β‐TiO2 and anatase phases is obtained for low Au content while only anatase form is favored when the initial Au rate rises. This investigation also suggests the inclusion of gold in the TiO2 structure. Although the optical bandgap of the different nanocomposites remains around 3 eV, the increase of Au content induces a shift of both valence and conduction edge bands to lower energy levels. The photocatalytic activity of TiO2/Au nanocomposites is assessed through the decolorization of different cationic and anionic dyes as model compounds. Regarding rhodamine and methylene blue dyes, the sample TiO2 modified with 3.5 wt% of Au presents the best performance. The relation between the structure of the nanocomposites and their capacity to degrade pollutants is discussed. [ABSTRACT FROM AUTHOR]

Supported gold nanoparticles have proven to be highly effective catalysts for the base-free oxidation of furfural, a compound derived from biomass. Their small size enables a high surface-area-to-volume ratio, providing abundant active sites for the reaction to take place. These gold nanoparticles serve as catalysts by providing surfaces for furfural molecules to adsorb onto and facilitating electron transfer between the substrate and the oxidizing agent. The role of the support in this reaction has been widely studied, and gold–support interactions have been found to be beneficial. However, the exact mechanism of furfural oxidation under base-free conditions remains an active area of research and is not yet fully understood. In this review, we delve into the essential factors that influence the selectivity of furfural oxidation. We present an optimization process that highlights the significant role of machine learning in identifying the best catalyst for this reaction. The principal objective of this study is to provide a comprehensive review of research conducted over the past five years concerning the catalytic oxidation of furfural under base-free conditions. By conducting tree decision making on experimental data from recent articles, a total of 93 gold-based catalysts are compared. The relative variable importance chart analysis reveals that the support preparation method and the pH of the solution are the most crucial factors determining the yield of furoic acid in this oxidation process.

Infiltrative cardiomyopathies are an increasingly recognized cause of heart failure warranting systematic evaluation. Given overlap of clinical and imaging findings among etiologies of infiltrative cardiomyopathies, comprehensive evaluation, including a history and physical examination, advanced cardiac imaging, and sometimes endomyocardial biopsy, is required for diagnosis. We report a case of infiltrative cardiomyopathy in which endomyocardial biopsy confirmed diagnosis of cobalt-induced cardiomyopathy. The novel teaching points highlighted by this case report include identification of heavy-metal toxicity as a cause of infiltrative cardiomyopathy, and the outline of a diagnostic approach and management for cobalt-induced cardiomyopathy. Résumé: Le fait que les cardiomyopathies infiltrantes sont de plus en plus reconnues comme la cause de l’insuffisance cardiaque justifie une évaluation systématique. Puisque les résultats cliniques et d’imagerie se recoupent entre les étiologies des cardiomyopathies infiltrantes, l’évaluation exhaustive, y compris les antécédents et l’examen physique, les techniques avancées en imagerie cardiaque et parfois la biopsie endomyocardique, est nécessaire au diagnostic. Nous présentons un cas de cardiomyopathie infiltrante pour lequel la biopsie endomyocardique a permis de confirmer le diagnostic d’une cardiomyopathie induite par le cobalt. Parmi les points à enseigner illustrés dans cette observation, on cite la reconnaissance de la toxicité des métaux lourds comme une cause de cardiomyopathie infiltrante, et la vue d’ensemble de l’approche diagnostique et de la prise en charge de la cardiomyopathie induite par le cobalt.

Strong metal–support interaction (SMSI) is a pivotal strategy in thermal catalysis; however, its application in photocatalysis leaves ample area for further development. A method inducing SMSI between earth-abundant metals, such as copper and TiO2, at room temperature, and thus hindering the agglomeration of copper species remains rarely reported. In this work, we achieved SMSI construction of TiO2 overlayers on Cu nanoparticles via a straightforward soft-chemistry method. SMSI coverage is stable even after high-temperature treatment in the air (500 °C), as demonstrated by chemical mapping and surface analysis. The method is more accurate than thermal reduction since it produces a metastable, highly active anatase phase. Interestingly, the TiO2 overlayer induces the formation of four-coordinated copper(II) species surrounded by oxygen atoms, resulting in coexisting CuO2 planes, which were monitored through high-resolution transmission electron microscopy and electron paramagnetic resonance spectroscopy. The stronger interfacial interaction by forming Ti–O–Cu bonding promotes charge carrier separation, producing twice as much H2 than the low interfacial interaction within a conventional photoactive system wherein copper was decorated onto TiO2. Our approach offers a rational design for SMSI materials in photocatalysis, which is extendable to other catalytic reactions. [ABSTRACT FROM AUTHOR]

Selective photocatalytic reduction of CO2 to value‐added fuels, such as CH4, is highly desirable due to its high mass‐energy density. Nevertheless, achieving selective CH4 with higher production yield on p‐block materials is hindered by non‐ideal adsorption of *CHO key intermediate and an unclear structure‐function relationship. Herein, we unlock the key reaction steps of CO2 and found a volcano‐type structure‐function relationship for photocatalytic CO2‐to‐CH4 conversion by gradual reduction of the p‐band center of the p‐block Bi element leading to formation of Bi‐oxygen vacancy heterosites. The selectivity of CH4 is also positive correlation with adsorption energy of *CHO. The Bi‐oxygen vacancy heterosites with an appropriate filled Bi‐6p orbital electrons and p band center (−0.64) enhance the coupling between C‐2p of *CHO and Bi‐6p orbitals, thereby resulting in high selectivity (95.2 %) and productivity (17.4 μmol g−1 h−1) towards CH4. Further studies indicate that the synergistic effect between Bi‐oxygen vacancy heterosites reduces Gibbs free energy for *CO‐*CHO process, activates the C−H and C=O bonds of *CHO, and facilitates the enrichment of photoexcited electrons at active sites for multielectron photocatalytic CO2‐to‐CH4 conversion. This work provides a new perspective on developing p‐block elements for selective photocatalytic CO2 conversion. [ABSTRACT FROM AUTHOR]

Imogolite nanotubes (INTs) are predicted as a unique 1D material with spatial separation of conduction and valence band edges but their large band gaps have inhibited their use as photocatalysts. The first step toward using these NTs in photocatalysis and exploiting the polarization‐promoted charge separation across their walls is to reduce their band gap. Here, the modification of double‐walled aluminogermanate INTs by incorporation of titanium into the NT walls is explored. The precursor ratio x = [Ti]/([Ge]+[Ti]) is modulated between 0 and 1. Structural and optical properties are determined at different scales and the photocatalytic performance is evaluated for H2 production. Although the incorporation of Ti atoms into the structure remains limited, the optimal condition is found around x = 0.4 for which the resulting NTs reveal a remarkable hydrogen production of ≈1500 µmol g−1 after 5 h for a noble metal‐free photocatalyst, a 65‐fold increase relative to a commercial TiO2‐P25. This is correlated to a lowering of the recombination rate of photogenerated charge carriers for the most active structures. These results confirm the theoretical predictions regarding the potential of modified INTs as photoactive nanoreactors and pave the way for investigating and exploiting their polarization properties for energy applications. [ABSTRACT FROM AUTHOR]

Integrating photonic crystals (PCs) into the design of a photocatalyst can significantly enhance its light‐harvesting capability. PCs can manipulate the propagation of light uniquely within a material and reduce its group velocity, thereby enhancing the absorption factor for photocatalysts. However, the slow photon effect in photoactive films with chiral nematic structures has not been reported yet, especially at the blue edge of the photonic bandgap. This work proposes a straightforward one‐pot method to fabricate various photonic films with chiral nematic, namely g‐C3N4/SiO2, TiO2/SiO2, and g‐C3N4/TiO2/SiO2. The sol‐gel biotemplating formulation using cellulose nanocrystals successfully leads to the elaboration of films exhibiting variable iridescent colors with photonic bandgap from UV to visible range. The tunable wavelength of the Bragg peak reflection offers the opportunity to access a region with a slow photonic effect, which directly impacts the light‐harvesting properties of the photoactive material. It is demonstrated that the H2 generation is significantly enhanced when the blue edge of the photonic bandgap position overlapped with the absorbance band of the photocatalyst. These results offer the opportunity to design photonic materials with chiral nematic structure and optimize the photocatalytic performance for energy application. [ABSTRACT FROM AUTHOR]

The aim was to determine whether gum Arabic (GA) supplementation prevents cognitive decline in type 2 diabetes, through stimulation of mitochondrial function in the hippocampus. Type 2 diabetic rats and controls were assigned to following groups for 16 weeks: Control + Water; Control + GA 10% w/v; Diabetes + Water; Diabetes + GA 10% w/v. Latency in water maze was shorter for Diabetes + GA compared to Diabetes + Water (P

Although titanium dioxide (TiO2) has a wide range of potential applications, the photocatalytic performance of TiO2 is limited by both its limited photoresponse range and fast recombination of the photogenerated charge carriers. In this work, the preparation of nitrogen (N)-doped TiO2 accompanied by the introduction of oxygen vacancy (Vo) has been achieved via a facile annealing treatment with urea as the N source. During the annealing treatment, the presence of urea not only realizes the N-doping of TiO2 but also creates Vo in N-doped TiO2 (N-TiO2), which is also suitable for commercial TiO2 (P25). Unexpectedly, the annealing treatment-induced decrease in the specific surface area of N-TiO2 is inhibited by the N-doping and, thus, more active sites are maintained. Therefore, both the N-doping and formation of Vo as well as the increased active sites contribute to the excellent photocatalytic performance of N-TiO2 under visible light irradiation. Our work offers a facile strategy for the preparation of N-TiO2 with Vo via the annealing treatment with urea. [ABSTRACT FROM AUTHOR]