Search

Carbon dioxide reduction together with aerobic oxidative cyclization using eosin Y-based light-harvesting photocatalysts remains a key challenge. In this study, we present the first-ever synthesis of unique in situ Se-infused eosin Y (Sein–EY) flexible photocatalysts through a simple one-pot method. The as-synthesized Sein–EY flexible film photocatalyst exhibits outstanding performance for the production of formic acid (204 μM in 2 h) and aerobic oxidative cyclization of thioamides via the formation of C–N/C–S bonds with outstanding yields (98.6%) when exposed to solar light. The presence of infused Se significantly extends the solar light absorption capacity of the Sein–EY photocatalyst, reaching up to 580 nm. This study opens up a new pathway for the rational design and synthesis of potentially effective Se-infused-EY photocatalysts through a simple and scalable method, enabling both solar chemical production and efficient one-pot three-component reactions. [ABSTRACT FROM AUTHOR]

Elevated global pollution level is the prime reason that contributes to the onset of various harmful health diseases. The products of Biginelli reaction are enormously used in the pharmaceutical industry as they have antiviral, antibacterial, and calcium channel modulation abilities. This work reports a novel eosin Y sensitized boron graphitic carbon nitride (EY‐Ben‐g‐C3N4) as a photocatalyst that efficiently produced 3,4‐dihydropyrimidine‐2‐(1H)‐one by the Biginelli reaction of benzaldehyde, urea, and methyl acetoacetate. The photocatalyst EY‐Ben‐g‐C3N4 showed a successful generation of 3,4‐dihydropyrimidine‐2‐(1H)‐one (Biginelli product) in good yield via photocatalysis which is an eco‐friendly method and has facile operational process. In addition to the production of Biginelli products, the photocatalyst also showed a remarkable NADH regeneration of 81.18%. The incorporation of g‐C3N4 with boron helps increase the surface area and the incorporation of eosin Y which is an inexpensive and non‐toxic dye, and in Ben‐g‐C3N4, enhanced the light‐harvesting capacity of the photocatalyst. The production of 3,4‐dihydropyrimidine‐2‐(1H)‐one and NADH by the EY‐Ben‐g‐C3N4 photocatalyst is attributed to the requisite band gap, high molar absorbance, low rate of charge recombination, and increased capacity of the photocatalyst to harvest solar light energy. [ABSTRACT FROM AUTHOR]

A schematic strategy is presented to overcome the problem of low photocatalytic performance of graphene. Herein, we synthesized nitrogen-doped graphene (NDG)-coupled acid fuchsin (AF) photocatalyst, i.e.; NDGCAF photocatalyst. The NDGCAF photocatalyst has excellent solar light harvesting ability, band gap suitability, and high molar extinction coefficient than the NDG photocatalyst. Due to these properties, the NDGCAF photocatalyst has the ability to oxidize aryl-vinyl into aryl-vinyl-aldehyde under the irradiation of visible light. In this context, it exhibited the utmost conversion efficiency of aryl-vinyl to aryl-vinyl-aldehyde with a good yield of 98.15%. Current research highlights the significant application of NDGCAF light-harvesting photocatalysts in the research field of organic transformations. [ABSTRACT FROM AUTHOR]

The generation of a low HOMO-LUMO energy gap makes organic polymer-based composites an important class of materials with outstanding catalytic efficiency. The present work describes the simple and direct synthesis of an excellent photocatalyst, PC (C26H16NO7S)n via doping of erythrosine-B dye on sulfone infused poly(2-amino thiophenol) assembly (PA, (C6H4NO2S)n). The O 1 s spectrum displays peaks at 531.8 eV and 533.3 eV, representing the O=C and O–C groups of the in-situ generated fluorescein loaded on PA surface. Through absorption study (Tauc's plot), the optical band gap (Eg) for polymer PA (2.9 eV) and photocatalyst PC (2.1 eV) has been calculated. Further, due to the efficient absorbance in the range of 400–600 nm with a low optical band gap, the applicability of the catalyst, PC has been checked in photocatalytic C–H activation in thiophene, and the generation of C–C bond with p-nitro aryldiazonium salt. [ABSTRACT FROM AUTHOR]

The combination of excellent electronic properties and thermal stability positions orange‐derived graphene quantum dots (GQDs) as promising materials for solar light‐based applications. Researchers are actively exploring their potential in fields such as photovoltaics, photocatalysis, optoelectronics, and energy storage. Their abundance, cost‐effectiveness, and eco‐friendly nature further contribute to their growing relevance in cutting‐edge scientific research. Furthermore, only GQDs are not much more effective in the UV‐visible region, therefore, required band gap engineering in GQDs material. In this context, we designed GQDs‐based light harvesting materials, which is active in UV‐visible region. Herein we synthesized GQDs coupled with 2,6‐diaminoanthrquninone (AQ), that is, GQDs@AQ light harvesting photocatalyst the first time for the oxidation of sulfide to sulfoxide under visible light. For the integrating reactions of sulfide in aerobic conditions under visible light by GQDs@AQ photocatalyst exhibit utmost higher photocatalytic activity than simple GQDs due to low molar extinction coefficient and slow recombination charges. The use of GQDs@AQ light harvesting photocatalyst, showed the excellent organic transformation efficiency of sulfide to sulfoxide with excellent yield (94%). The high efficiency and excellent yield of 94% indicate the effectiveness of GQDs@AQ as a photocatalyst for these specific organic transformations. [ABSTRACT FROM AUTHOR]

Fluorinated and enzymatic chemicals are widely used in society due to their chemical, physical, and biological qualities. Nevertheless, despite their vital importance, present approaches to adding fluorine to molecules and regenerating enzyme cofactors have serious flaws. For instance, numerous approaches are photocatalytic and employ stoichiometric counterparts of heavy metals. Prevailing photocatalytic approaches, on the other hand, show very poor activity, and selectivity has not been attained by heterogeneous photocatalysis, despite the several benefits such a method would provide. Here, we show how heterogeneous photocatalysis may be used to selectively create C(sp3)‐F bonds and 1,4‐NADH regeneration cofactor. Employing NiS‐NiO/S‐g‐C3N4 nanocomposite photocatalyst as a photocatalyst, NAD+ and Selectfluor as an acceptor and mild fluorine donor, effective 1,4‐NADH regeneration, and decarboxylative fluorination of carboxylic acids can be attained in very short reaction times. Furthermore, NiS‐NiO/S‐g‐C3N4 nanocomposite photocatalyst exhibits outstanding levels of robustness and photo‐catching capacity. These aspects, attached to the mild environment of the reaction scheme, exhibit a breakthrough toward the sustainable cofactor of 1,4‐NADH regeneration and synthesis of fluorinated compounds. [ABSTRACT FROM AUTHOR]

Topological insulators, a class of materials possessing bulk bandgap and metallic surface states with a topological nontrivial symmetry, are considered promising candidates for emerging quantum and optoelectronic applications. However, achieving scalable growth and control over the parameters including thickness, carrier density, bulk bandgap, and defect density remains a challenge in realizing such applications. In this work, we show the scalable growth of topological insulator alloys Bi2Se(3−x)Sx and demonstrate composition-tunable bandgap, using chemical vapor deposition (CVD). A bandgap increase of up to ∼40% at a sulfur concentration of ∼15% is demonstrated. Correspondingly, the real part (n) of the refractive index is reduced in the alloy by ∼25% relative to that of Bi2Se3. Additionally, electronic transport measurements indicate a bulk p-type doping and field-effect tunable metallic surface states of the alloy. This work paves the way for the controlled growth of topological insulators, free from surface-state pinning, suitable for quantum optoelectronics and spintronics applications. [ABSTRACT FROM AUTHOR]

Aloe vera‐derived graphene (ADG) coupled system photocatalyst, mimicking natural photosynthesis, is one of the most promising ways for converting solar energy into ammonia (NH3) and nicotinamide adenine dinucleotide (NADH) that have been widely used to make the numerous chemicals such as fertilizer and fuel. In this study, we report the synthesis of the aloe vera‐derived graphene‐coupled phenosafranin (ADGCP) acting as a highly efficient photocatalyst for the generation of NH3 and regeneration of NADH from nitrogen (N2) and oxidized form of nicotinamide adenine dinucleotide (NAD+). The results show a benchmark instance for mimicking natural photosynthesis activity as well as the practical applications for the solar‐driven selective formation of NH3 and the regeneration of NADH by using the newly designed photocatalyst. [ABSTRACT FROM AUTHOR]

Melanoma and nonmelanoma skin cancers are among the most prevalent and most lethal forms of skin cancers. To identify new lead compounds with potential anticancer properties for further optimization, in vitro assays combined with in‐silico target fishing and docking have been used to identify and further map out the antiproliferative and potential mode of action of molecules from a small library of compounds previously prepared in our laboratory. From screening these compounds in vitro against A375, SK‐MEL‐28, A431, and SCC‐12 skin cancer cell lines, 35 displayed antiproliferative activities at the micromolar level, with the majority being primarily potent against the A431 and SCC‐12 squamous carcinoma cell lines. The most active compounds 11 (A431: IC50 = 5.0 μM, SCC‐12: IC50 = 2.9 μM, SKMEL‐28: IC50 = 4.9 μM, A375: IC50 = 6.7 μM) and 13 (A431: IC50 = 5.0 μM, SCC‐12: IC50 = 3.3 μM, SKMEL‐28: IC50 = 13.8 μM, A375: IC50 = 17.1 μM), significantly and dose‐dependently induced apoptosis of SCC‐12 and SK‐MEL‐28 cells, as evidenced by the suppression of Bcl‐2 and upregulation of Bax, cleaved caspase‐3, caspase‐9, and PARP protein expression levels. Both agents significantly reduced scratch wound healing, colony formation, and expression levels of deregulated cancer molecular targets including RSK/Akt/ERK1/2 and S6K1. In silico target prediction and docking studies using the SwissTargetPrediction web‐based tool suggested that CDK8, CLK4, nuclear receptor ROR, tyrosine protein‐kinase Fyn/LCK, ROCK1/2, and PARP, all of which are dysregulated in skin cancers, might be prospective targets for the two most active compounds. Further validation of these targets by western blot analyses, revealed that ROCK/Fyn and its associated Hedgehog (Hh) pathways were downregulated or modulated by the two lead compounds. In aggregate, these results provide a strong framework for further validation of the observed activities and the development of a more comprehensive structure–activity relationship through the preparation and biological evaluation of analogs. [ABSTRACT FROM AUTHOR]

Photocatalysis is one of the most promising methods for producing organic compounds with a renewable source of energy. Two‐dimensional covalent organic frameworks (2D COFs) are a type of polymer that has developed as a potential light‐harvesting catalyst for artificial photosynthesis with a design‐controllable platform that might be developed into a new type of cost‐effective and metal‐free photocatalyst. Here, we present a two‐dimensional covalent organic framework synthesis technique as a low‐cost and highly efficient visible light active flexible photocatalyst for C–H bond activation and dopamine regeneration. 2D COF were synthesized from tetramino‐benzoquinone (TABQ) and terapthaloyl chloride monomer through condensation polymerization reaction and the resultant photocatalyst have remarkable performance due to its visible light‐harvesting capacity, appropriate band gap, and highly organized π‐electron channels. The synthesized photocatalyst is capable to convert dopamine into leucodopaminechrome with a higher yield (77.08%) and also capable to activate the C–H bond between 4‐nitrobenzenediazonium tetrafluoroborate and pyrrole. [ABSTRACT FROM AUTHOR]

Graphene is one of the amazing present encroachments in current research area of science and one of the utmost fascinating materials for relevance in cutting-edge research. Herein, we designed lemon-derived heteroatoms-doped graphene quantum dots (S, N-GQDs) based photocatalyst for the first time. For the integrating reactions of amines in aerobic conditions under solar light by S, N-GQDs photocatalyst exhibit utmost higher photocatalytic activity than simple oxygen-doped graphene quantum dots (O-GQDs) due to slow recombination charges. The mechanisms accountable for the drastically increased photocatalytic activity of S, N-GQDs in solar light responsive integrating reactions of amines in aerobic conditions into the corresponding derivative of imines are also completely scrutinized. [ABSTRACT FROM AUTHOR]

Photocatalytic processes triggered by graphene‐based photocatalysts under solar light have sparked interest as a new sort of instrument for solar chemical synthesis. Herein we investigated self‐assembled graphene quantum dots (GQDs)/NiSe‐NiO composite photocatalyst for organic transformation as well as dye degradation. The synthesized GQDs/NiSe‐NiO composite photocatalyst has an excellent suitable band gap, high molar extinction coefficient, low toxicity and chemical/thermal stability. The GQDs/NiSe‐NiO composite photocatalyst emerges as a new standard for sulfur oxidation and dye degradation reactions under homemade LED light with high yield. [ABSTRACT FROM AUTHOR]