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To meet the energy demands artificial photosynthesis is playing the most promising role these days. Using sunlight directly in a manner that can provide useful chemicals is a sustainable means of generating energy. Studies are going on in this context to make better and effective photocatalyst. In this paper, we study the synthesis of flower‐like graphene quantum dots‐based fuschin (GQDF) photocatalyst from lemon, which is created by a green and sustainable process that is effective and environment friendly. The UV‐visible spectra of prepared GQDF showed a high molar extinction coefficient. A flower‐like GQDF photocatalyst has better catalytic efficiency for the selective creation and regeneration of the NAD(P)H cofactor. A newly designed flower‐like GQDF photocatalyst is used as one of its most effective photocatalysts as they have several additional applications in the removal of CO2 and aqueous contaminants like heavy metals. [ABSTRACT FROM AUTHOR]

Covalent triazine frameworks (CTFs), belonging to the super‐family of covalent organic frameworks, have attracted significant attention as a new type of photosensitizer due to the superb light‐harvesting ability and efficient charge transfer originating from the large surface area. However, the wide optical band gap in CTFs, which is larger than 3.0 eV, hinders the efficient light harvesting in the visible range. To overcome this limitation, we developed the new type CTFs photocatalyst based on the donor–acceptor conjugation scheme by using melamine (M) and 2,6‐diaminoanthraquinone (AQ) as monomeric units. The melamine‐2,6‐diaminoanthraquinone‐based covalent triazine frameworks (M‐AQ‐CTFs) photocatalyst shows the excellent light‐harvesting capacity with high molar extinction coefficient, and the suitable optical band gap involving the internal charge transfer character. Combination of M‐AQ‐CTFs and artificial photosynthetic system including the organometallic rhodium complex, acting as an electron mediator, exhibited the excellent photocatalytic efficiency for the regeneration of the nicotinamide cofactors such as NAD(P)H. In addition, this photocatalyst showed the high photocatalytic efficiency for the metal‐free aerobic oxidation of sulfide. This study demonstrates the high potential of CTFs photocatalyst with the donor–acceptor conjugated scheme can be actively used for artificial photosynthesis. [ABSTRACT FROM AUTHOR]

Summary: Direct conversion of sunlight into value‐added chemicals through artificial photosynthesis has been recognized as one of the most promising ways to address the global energy needs and to utilize the sustainable energy source. Even though the various semiconducting materials have been used for the solar‐driven production of chemicals, many experimental efforts have been still focusing on developing clean and reusable photocatalysts. In this study, we report the new metal‐free graphitic carbon nitride (g‐C3N4) composite including anthracene moieties as a primary photosensitizer. The morphological and electronic structure of anthracene‐based g‐C3N4 (An‐g‐C3N4) composite were characterized by optical spectroscopies, electrochemical measurements, and theoretical calculations based on density‐functional theory. The An‐g‐C3N4 composite exhibited outstanding photocatalytic efficiency for the regenerations of NAD(P)H cofactors owing to the prominent charge‐transferred character and the superb light absorption. This study demonstrates that the catalytic reaction employing the combination of An‐g‐C3N4 photocatalyst and Z‐scheme nature would be a suitable option for artificial photosynthesis. [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]

• This manuscript focuses on how structural ordering can facilitate the formation of formic at ultra-low potential, which is a critical challenge via photocatalysis. • Human dependency on fossil fuels not only spikes the CO2 levels in the atmosphere but also depletes the limited energy resources. • The photocatalyst-enzyme integrated artificial system emerged as a benchmark for CO2 fixation solving both the energy crisis and carbon emission simultaneously. • Herein a TBE-Y photocatalyst designed by coupling triptycene (T) with eosin-Y (EY) through friedel craft reaction shows excellent solar light harvesting property, high molar extinction coefficient, and appropriate band-gap. • The as-synthesized 3D polymeric TBE-Y photocatalyst exhibits high NADH regeneration (78.77%) which when consecutively coupled with enzyme (formate dehydrogenase) via electron mediator produces HCOOH from CO2 in high yield. Carbon dioxide, one of the primary greenhouse gasses leading to global warming, ocean acidification, and climate change is an obnoxious concern. Human dependency on fossil fuels not only spikes the CO 2 level but also depletes the limited energy resources. The horrendous impact of carbon footprint has made the reduction of CO 2 into solar fuel an indispensable task. The photocatalyst-enzyme integrated artificial system has emerged as a benchmark for CO 2 fixation solving both the energy crisis and carbon emission simultaneously. Herein a TBE-Y photocatalyst designed by coupling triptycene (T) with eosin-Y (EY) through Friedel Craft reaction shows excellent solar light harvesting property, high molar extinction coefficient, and appropriate band-gap. The as-synthesized 3D polymeric TBE-Y photocatalyst exhibits high NADH regeneration (78.77%) which when consecutively coupled with enzyme (formate dehydrogenase) via electron mediator produces HCOOH (189.34 μmol) from CO 2 in high yield in 2 h. The graphical abstract shows the formation and regeneration of HCOOH from CO 2 and NADH respectively through TBE-Y photocatalyst under solar light irradiation. The TBE-Y photocatalyst was formed through Friedel craft reaction by the coupling of Triptycene and Eosin-Y, which is utilized for HCOOH formation from CO 2 in the presence of Solar light. Formic acid and NADH regeneration have a wide application in pharmaceutical companies. [Display omitted] [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]

Abstract: The conversion of CO2 to valuable solar fuels by means of solar energy using metal‐free flexible film photocatalysts is an appealing strategy. Here we demonstrate a three dimensional aromatic polymer (3DAP) derived from triptycene (TC) as a metal free, stable and highly efficient visible light responsive flexible film photocatalyst for selective solar fuel production from CO2. For this research work, the polymerization of TC by the Diels–Alder reaction is exploited for the first time as a new synthetic approach for the construction of three dimensional aromatic polymer photocatalyst. The visible‐light harvesting ability, band gap suitability, high Brunauer–Emmett–Teller (BET) surface area and electron transfer capability via interconnecting 3D chain of 3DAP contribute to the excellent performance of the film photocatalyst as evident from 91.09 % NADH regeneration and 225.12 μmol of formic acid production. This work provides important insights into the design of flexible polymer film photocatalyst for selective solar fuel formation from CO2 and is expected to trigger further interest in sustainable solar energy conversion applications such as tailorable and wearable devices. [ABSTRACT FROM AUTHOR]

Abstract: The conversion of CO2 to valuable solar fuels by means of solar energy using metal‐free flexible film photocatalysts is an appealing strategy. Here we demonstrate a three dimensional aromatic polymer (3DAP) derived from triptycene (TC) as a metal free, stable and highly efficient visible light responsive flexible film photocatalyst for selective solar fuel production from CO2. For this research work, the polymerization of TC by the Diels–Alder reaction is exploited for the first time as a new synthetic approach for the construction of three dimensional aromatic polymer photocatalyst. The visible‐light harvesting ability, band gap suitability, high Brunauer–Emmett–Teller (BET) surface area and electron transfer capability via interconnecting 3D chain of 3DAP contribute to the excellent performance of the film photocatalyst as evident from 91.09 % NADH regeneration and 225.12 μmol of formic acid production. This work provides important insights into the design of flexible polymer film photocatalyst for selective solar fuel formation from CO2 and is expected to trigger further interest in sustainable solar energy conversion applications such as tailorable and wearable devices. [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]

[Display omitted] • Artificial photosynthesis. • Easy to make polydopamine modified sulphur doped GCN photocatalyst for generation of HCOOH from CO 2. • P@SGCN photocatalyst utilizes in the artificial photosynthetic system for the highly selective generation of formic acid from CO 2 under sun ray irradiation. The photocatalytic transformations of CO 2 into solar chemicals are a promising way in views of green energy and environmental sustainability. Improving the low catalytic performance and poor selectivity of the photocatalysts are one of the great challenges in this field. By mimicking the natural photosynthesis and taking advantage of the enzyme's high specificity and efficiency, we designed the metal-free photocatalyst combined to an enzyme in order to synergistically solve the stated problems. In this work, we developed a metal-free polydopamine (P) modified sulfur-doped graphitic carbon nitride (P@SGCN) photocatalyst for the regeneration of NADH and the highly selective production of formic acid, HCOOH, from CO 2. Our study shows a new way for the applications of polydopamine-modified photocatalysts to produce the solar chemicals/fuels from CO 2. [ABSTRACT FROM AUTHOR]

A spherical photocatalyst to emulate natural photosynthesis for the production of formic acid from CO 2. [Display omitted] • Efficient photocatalytic formic acid production from CO 2 has been carried out by a novel Bromophenol-Bakelite (BPB) composite. • The as prepared photocatalyst was characterized by several characterization techniques to determine the physio-chemical properties. • The prepared photocatalyst is found to be visible light active and was further used for the regeneration of NADH and formation of formic acid. • The yield for solar light driven NADH regeneration and formic acid production by this photocatalyst was found to be 82.52 % and 220 μmol respectively. The conversion of carbon dioxide (CO 2) to various chemical compounds is an attractive solution to overcome the global energy and environmental crisis. However, the chemical stability of CO 2 hinders the many chemical applications such as photochemical conversion processes. In this work, we developed the efficient photocatalytic reactions for the production of formic acid from CO 2 and the NADH regeneration by employing a novel Bromophenol-Bakelite (BPB) composite. We synthesized the BPB photocatalyst with the bromophenol blue dye-doped inside the Bakelite matrix. The BPB-composite showed the excellent photocatalytic abilities combined to the photocatalyst − enzyme coupled artificial photosynthetic system. For the production of formic acid and the NADH regeneration, the catalytic efficiencies of BPB-composite were much higher than those of bromophenol. Our approach will open up the new way toward the selective productions of solar chemicals directly converted from CO 2 via the artificial photosynthesis. [ABSTRACT FROM AUTHOR]

We performed high-level ab initio quantum chemical calculations, incorporating higher-order excitations, spin–orbit coupling (SOC), and the Gaunt interaction, to calculate the electron affinities (EAs) of alkaline earth (AE) metal atoms (Ca, Sr, Ba, and Ra), which are notably small. The coupled-cluster singles and doubles with perturbative triples [CCSD(T)] method is insufficient to accurately calculate the EAs of AE metal atoms. Higher-order excitations proved crucial, with the coupled-cluster singles, doubles, and triples with perturbative quadruples [CCSDT(2)Q] method effectively capturing dynamic electron correlation effects. The contributions of SOC (ΔESOs) to the EAs calculated using the multireference configuration interaction method with the Davidson correction, including SOC, positively enhance the EAs; however, these contributions are overestimated. The Dirac–Hartree–Fock (DHF)-CCSD(T) method addresses this overestimation and provides reasonable values for ΔESO (ΔESO−D). Employing additional sets of diffuse and core–valence correlation basis sets is critical for accurately calculating the EAs of AE metal atoms. The contributions of the Gaunt interaction (ΔEGaunt) to the EAs of AE metal atoms are negligible. Notably, the CCSDT(2)Q with the complete basis set limit + ΔESO−D + ΔEGaunt produced EA values for Ca, Sr, and Ba that closely aligned with experimental data and achieved accuracy exceeding the chemical accuracy. Based on our findings, the accurately proposed EA for Ra is 9.88 kJ/mol. [ABSTRACT FROM AUTHOR]

Introduction: Neonatal sepsis is an infection in newborns that may be caused by bacteria, fungi, or viruses and has a high death and morbidity rate. The clinical presentation of sepsis may be rather general, making it challenging to make a diagnosis. While blood culture is the most accurate method to diagnose sepsis, it is also time-consuming. Because of this, it is crucial to locate other biomarkers like C-reactive protein (CRP), high sensitive C-reactive protein (hs-CRP), and procalcitonin (PCT) that may aid in early identification. Aim: To learn about the bacterial composition of suspected cases of neonatal sepsis in a tertiary care hospital in western Uttar Pradesh and how that composition relates to the biomarkers CRP, hs-CRP, and PCT. Materials and Methods: Hundred people who fulfilled the study’s inclusion criteria were included. All neonatal venous blood samples have been obtained after receiving written informed permission from either parent. The conventional method was used to perform the blood culture. The ELISA technique has been used to determine hs-CRP along with serum PCT levels, while the latex agglutination test was utilized for CRP detection. Result: A total of 100 cases were enrolled, 78% presented within 3 days of birth. Blood culture was positive in 33 neonates (33%). There were 17 Gram-positive, 15 Gram-negative, and in all 2 cases with poly bacterial culture. CRP positivity rate was significantly higher in culture positive (57.6%) as compared to culture-negative neonates (25.4%). It was shown that a CRP >6 mg/l level was sensitive at 57.6% and specific at 74.6%. hs-CRP has a 100% sensitivity and 47.8% specificity. The PCT’s sensitivity was 69.7%, whereas its specificity was 89.6%. Conclusion: PCT is more specific for detecting sepsis, but hs-CRP is more sensitive than CRP. The combination of PCT along with hs-CRP has a negative predictive value and high sensitivity compared to other markers. Thus, the most accurate predictors of neonatal sepsis would be a combination of factors. [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]

Functionalized graphene quantum dots (fGQDs) as visible-light-harvesting photocatalysts for solar fuel production from CO2 is explored for the first time. The highly efficient light-harvesting fGQDs photocatalyst upon integration with the biocatalyst performs highly selective CO2 reduction to formic acid. The results are a benchmark example of GQD based materials as photocatalysts for selective production of solar fuels from CO2 and opens up possibilities for greener synthesis of other value added chemicals. [ABSTRACT FROM AUTHOR]

Functionalized graphene quantum dots (fGQDs) as visible-light-harvesting photocatalysts for solar fuel production from CO2 is explored for the first time. The highly efficient light-harvesting fGQDs photocatalyst upon integration with the biocatalyst performs highly selective CO2 reduction to formic acid. The results are a benchmark example of GQD based materials as photocatalysts for selective production of solar fuels from CO2 and opens up possibilities for greener synthesis of other value added chemicals. [ABSTRACT FROM AUTHOR]