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Glucose, an abundant and renewable form of biomass, has garnered significant attention in research for its conversion into high‐value chemicals such as gluconic acid. Traditional methods for biomass transformation typically involve high energy input, elevated temperature, pressure, and costly systems. In contrast, photocatalysis emerges as a promising approach to produce organic molecules under mild conditions, harnessing energy from natural sunlight or lamps. This study presents the nitrogen‐enriched graphene with zeolite second Mobil–5 (NenG/ZSM‐5) photocatalyst, evaluated for generating high‐value chemicals (gluconic acid and leucodopaminechrome) under solar light irradiation. The NenG/ZSM‐5 photocatalyst, synthesized from nitrogen‐doped graphene and ZSM‐5, successfully converted dopamine into leucodopaminechrome (71.54 %) — a critical step in dopamine regeneration and transformed glucose into gluconic acid (85 %). The addition of ZSM‐5 to NenG provided stability and enhanced product selectivity. The outstanding performance of the NenG/ZSM‐5 photocatalyst can be attributed to its heightened solar light harvesting potential, appropriate energy band gap, and uniformly arranged π‐electron channels. This research focuses on solar conversion of glucose to gluconic acid and dopamine regeneration, with potential for further exploration in the research domain. [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]

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]

The photocatalytic oxidation and generation/regeneration of amines to imines and leucodopaminechrome (LDC)/NADH are subjects of intense interest in contemporary research. Imines serve as crucial intermediates for the synthesis of solar fuels, fine chemicals, agricultural chemicals, and pharmaceuticals. While significant progress has been made in developing efficient processes for the oxidation and generation/regeneration of secondary amines, the oxidation of primary amines has received comparatively less attention until recently. This discrepancy can be attributed to the high reactivity of imines generated from primary amines, which are prone to dehydrogenation into nitriles. In this study, we present the synthesis and characterization of a novel polymer‐based photocatalyst, denoted as PMMA‐DNH, designed for solar light‐harvesting applications. PMMA‐DNH incorporates the light‐harvesting molecule dinitrophenyl hydrazine (DNH) at varying concentrations (5%, 10%, 20%, 30%, and 40%). Leveraging its high molar extinction coefficient and slow charge recombination, the 30% DNH‐incorporated PMMA photocatalyst proves to be particularly efficient. This photocatalytic system demonstrates exceptional yields (96.5%) in imine production and high generation/regeneration rates for LDC/NADH (65.27%/78.77%). The research presented herein emphasizes the development and application of a newly engineered polymer‐based photocatalyst, which holds significant promise for direct solar‐assisted chemical synthesis in diverse commercial applications. [ABSTRACT FROM AUTHOR]

Selective radical‐radical coupling of terminal alkynes and thiol has been broadly used in chemical synthesis, providing plausible entries to the formation of anti‐Markovnikov products. Because of the selective control and Kharasch effect, the formation of Markovnikov products still remains an immense challenge. Herein, we designed a covalent organic polymer, poly(naphthalene 1,4,5,8‐tetracarboxylic dianhydrideimide‐benzoquinone) through in situ polymerization on activated flexible carbon cloth to function as a light harvester material for selective Markovnikov radical‐radical coupling of terminal alkynes and thiol. Mechanistic explorations verified that cross‐coupling between radical of terminal alkynes and thiol might be the key route in this organic transformation, such as C—S bond formation. This selective radical‐radical Markovnikov of cross‐coupling protocol provide an opportunity to assist the synthesis of valuable vinyl sulfide. Additionally, the synthesized material has been explored as liquefied petroleum gas (LPG) sensor for 0.5, 1.0, 1.5, and 2.0 vol% LPG, respectively. At 2.0 vol% LPG, it shows maximum sensor response as 635.29. Least response and recovery times are 2.44 and 1.0 s, respectively. [ABSTRACT FROM AUTHOR]

Summary: Development of ecofriendly and low‐cost highly efficient photocatalysis is of importance in the field of chemical synthesis. Currently, various metals‐based organic materials, metal oxide nanoparticles, and metal nanomaterials have been urbanized as light harvesting photocatalysts for direct carbon (C)‐hydrogen (H) arylation of aryl diazonium salts and heteroarenes. These light harvesting photocatalysts, however, still suffer from poor stability, reusability problem, high cost, or less selectivity. Herein, we report the fabrication of a novel chitosan‐based fluorescein isothiocyanate (CBFITC) film photocatalyst and demonstrate its tremendous photocatalytic activity, high yields (97 ± 0.015%), selectivity (99%), and reusability to catalyze the metal free solar‐light‐mediated direct CH arylation of aryl diazonium salts and heteroarenes at ambient temperature. Moreover, CBFITC film photocatalyst can be recycled more than five times without loss of activity, verifying this photocatalyst excellent light harvesting ability and stability. The present approach to fabricate a metal‐free film photocatalyst with the suitable band gap will be a new platform for efficient photocatalytic reaction and provide a new insight into the solar chemical synthesis. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: Photoredox C—H bond formation can proceed in aerobic environment under solar light and has therefore become attractive. Nowadays, different types of expensive novel metal complexes and nanomaterials have been urbanized as photocatalysts for direct C—H bond formation in between derivatives of heteroarenes (HAs) and aryl diazonium salts. These photocatalysts, however, still suffer from poor stability, high cost, and decay. Herein, a graphitic carbon nitride‐based fluorescein isothiocyanate (g‐C3N4–FITC) film photocatalyst has been reported, which shows excellent light harvesting ability, and band gap suitability to catalyze the metal free direct C—H arylation of HAs under solar light at ambient temperature. Moreover, the g‐C3N4–FITC film photocatalyst can be reused four times without significant loss of activity, confirming the excellent photocatalytic stability. The current strategy to construct a g‐C3N4–FITC film photocatalyst for direct C—H arylation opens a new path towards replacing metal‐based catalysts in fine chemical synthesis. [ABSTRACT FROM AUTHOR]

As most promising organic semiconductors, and polymeric materials have concentrated much attention due to their thermochemical stability, chemical inertness, non-toxicity, excellent photoelectrical properties, low cost, and abundance of raw materials. However, the light-harvesting polymeric material graphitic carbon nitride (g-C 3 N 4) has a limited ability to absorb light in the region below 420 nm because of its wide optical band gap. As one method to enhance the character of light harvesting and optical properties, such as EB-T (Eriochrome Black-T) has been used, and easy to prepare g-C 3 N 4 based EB-T (g-C 3 N 4 @EB-T) composite photocatalyst, which has tuned the energy gap of pristine g-C 3 N 4. In this article, we synthesized a new classic type of g-C 3 N 4 @EB-T composite photocatalyst by the copolymerization method. The EB-T moieties serve as external photosensitizing components in this composite photocatalyst. Compared to the initial materials, the g-C 3 N 4 @EB-T composite photocatalyst shows exceptional yields in the regeneration and formation of NADH and C(sp3) F bond. [Display omitted] • A novel photocatalytic system utilizing g-C 3 N 4 is proposed for the production and regeneration of the C(sp3)-F bond and NADH, crucial components in pharmaceutical synthesis. • The proposed system consists of a self-assembled g-C 3 N 4 composite that efficiently captures and utilizes sunlight to activate the reactions. • Ethylbenzene is used as a representative substrate for C(sp3)-F bond generation, while NAD+ serves as a model for NADH regeneration (65% yield). • The system exhibits remarkable selectivity and efficiency for both reactions and operates under mild conditions and at room temperature, making it suitable for large-scale synthesis. • This research highlights g-C 3 N 4 's potential as a versatile and environmentally friendly photocatalytic platform for various chemical transformations under sunlight. [ABSTRACT FROM AUTHOR]

Photocatalytic CO2 reduction for solar fuel production has attracted considerable attention as it can simultaneously reduce the effects of worldwide fossil-fuel shortage and global warming. As a means to achieve this we herein report the facile and eco-friendly synthesis of highly active carbon nanodots-silica hybrid photocatalyst (CNDSH) by a reverse microemulsion method with a nonionic surfactant. The photocatalyst-biocatalyst coupled system developed using CNDSH as photocatalyst functions efficiently to carry out high NADH regeneration (74.10±0.17 %) followed by its consumption in exclusive formic acid production (203.33±1.9 μmol) from CO2. This research work is a benchmark example of carbon nanodots-silica hybrid photocatalyst system for solar fuel production and expected to trigger further interest in the development of efficient and eco-friendly CO2 reduction systems. [ABSTRACT FROM AUTHOR]

Photocatalytic CO2 reduction for solar fuel production has attracted considerable attention as it can simultaneously reduce the effects of worldwide fossil-fuel shortage and global warming. As a means to achieve this we herein report the facile and eco-friendly synthesis of highly active carbon nanodots-silica hybrid photocatalyst (CNDSH) by a reverse microemulsion method with a nonionic surfactant. The photocatalyst-biocatalyst coupled system developed using CNDSH as photocatalyst functions efficiently to carry out high NADH regeneration (74.10±0.17 %) followed by its consumption in exclusive formic acid production (203.33±1.9 μmol) from CO2. This research work is a benchmark example of carbon nanodots-silica hybrid photocatalyst system for solar fuel production and expected to trigger further interest in the development of efficient and eco-friendly CO2 reduction systems. [ABSTRACT FROM AUTHOR]

The photocatalyst-enzyme coupled system for artificial photosynthesis process is one of the most promising methods of solar energy conversion for the synthesis of organic chemicals or fuel. Here we report the synthesis of a novel graphene-based visible light active photocatalyst which covalently bonded the chromophore, such as multianthraquinone substituted porphyrin with the chemically converted graphene as a photocatalyst of the artificial photosynthesis system for an efficient photosynthetic production of formic acid from CO2. The results not only show a benchmark example of the graphene-based material used as a photocatalyst in general artificial photosynthesis but also the benchmark example of the selective production system of solar chemicals/solar fuel directly from CO2. [ABSTRACT FROM AUTHOR]

The Cover shows the exclusive production of formic acid from CO2 using a carbon nanodots‐silica hybrid photocatalyst system.In their Full Paper, R. K. Yadav et al. report a new carbon nanodots‐silica hybrid material (CNDSH) as a highly active photocatalyst for the photocatalytic‐biocatalytic coupled selective solar fuel production system from CO2. The CNDSH photocatalyst was obtained by a facile and ecofriendly reverse microemulsion method with a nonionic surfactant. This work would serve as a benchmark example of a carbon nanodots‐silica hybrid photocatalyst system for solar fuel production and is expected to trigger further interest in the development of efficient and ecofriendly solar CO2 reduction systems. [ABSTRACT FROM AUTHOR]

[Display omitted] • Use of non-toxic/least toxic chemicals. • Generation of least studied ester-linked covalent organic polymer. • Crystalline nanosheet generation (average crystallite size = 43.5 nm, crystallinity = 90.5 %). • Excellent photocatalytic activity with high selectivity for C-H activation and C-C bond formation reaction. Among all polymeric materials, the chemistry of covalent organic polymers has been the least covered in the field of photocatalysis due to the rare availability of design and synthetic protocols. In the present work, we have come up with an efficient design of a one-dimensional Covalent Organic polymer (COP) (S-COP) through the ester-linked co-polymerization of Erythrosine B with 2,2′-Dithiodibenzoic acid (2,2′-DDB). The COP was synthesized via the facile one-pot solvothermal method. The XRD data analysis favors high crystalline nanoscale polymeric sheet generation (S-COP , 90.5 % & 43.5 nm). The HOMO-LUMO calculation through an electrochemical study as well as Tauc's plot showed 2.1 eV band gap. In this order, S-COP , a metal-free polymeric material was observed as an effective photocatalyst in the solar-driven photocatalytic reaction of heteroarenes with aryl diazonium salts via direct C-H arylation (High yield (∼98 %), and high selectivity (∼98 %)). [ABSTRACT FROM AUTHOR]

Abstract: Herein, for the first time, CuAlGaO4 is demonstrated as an efficient visible-light-active (band-gap of 1.87eV, λ ≥420nm) photocatalyst for solar H2 production. The CuAlGaO4 prepared by solid-state method is capable of producing 3214μmol of H2 per hour from H2S photodecomposition under visible-light irradiation with quantum yield of 10.8% at 550nm. Loading with 1wt.% NiO enhances the rate of H2 generation of the photocatalyst to 3616μmolh−1 with quantum yield of 12.7% at 550nm. The CuAlGaO4 exhibits a spinel structure with particle size varying from a few nanometers to a few micrometers. The regenerated catalysts validate the stability and the reusability. [Copyright &y& Elsevier]

An asymmetric artificial photosynthesis system that comprises an efficient method of nicotinamide cofactor regeneration under visible light employing a graphene-based light harvesting photocatalyst and its subsequent utilization in an enzyme-catalyzed asymmetric reduction of prochiral ketones is described. [ABSTRACT FROM AUTHOR]