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Photoelectrochemical (PEC) systems are inefficient, probably due to charge carrier mobility, recombination rate, and solar light absorption. Fabricating semiconductor-metal sulfide nanocomposites and nanostructured materials can improve the absorption of solar radiation, electron–hole separation, transport, and hydrogen (H2) and oxygen generation to resolve the world's energy dilemma. The vanadium-doped (V) layered graphitic carbon nitride (g-CN)/MoS2 (MS) nanocomposite was synthesized employing two-step solvent evaporation and thermal condensation. This multilayer V-doped g-CN/MS nanocomposite broke down methyl red dye in 60 min under sunlight. Due to visible light absorption, the V-doped g-CN-MS nanostructure degrades the dye by 97.84%. We found that at 3.0 wt % V-doped g-CN/MS coated on TiO2 nanorods. The catalyst nanocomposites displayed a high photocurrent density of 23.72 mA cm–2 and a H2 production rate of 4477 mol h–1 cm–2. Additionally, the microstructure, optical absorption behavior, and electrical conductivity were all shown to contribute to these impressive PEC characteristics. The V-modified g-CN/MS nanocomposite structures are effective and regulated PEC catalysts, and this study suggests ways to improve PEC water splitting and degradation. [ABSTRACT FROM AUTHOR]

A superficial, one step thermal polycondensation method has been employed for the manifestation of graphene like graphitic carbon nitride (g-C3N4) catalyst. The as synthesized g-C3N4 was well characterized by SEM and EDAX analysis, XRD, ATR-IR, FTIR, Fluorescence spectroscopy, Raman spectroscopy and UV–Visible spectroscopy which provide structural, morphological assemblage relating to the structure of g-C3N4. The g-C3N4 showed that an outstanding photochemical stability, morphology, conductive carbon framework and superior photocatalytic activity. The band gap value of g-C3N4 is 2.34 eV determined using Tauc plot. Due to low band gap (2.33 eV) and unique morphology which provides high separation and migration ability of the photogenerated charges, the g-C3N4 shows enhanced photocatalytic activity for the removal of many organic dyes such as Rhodamine B (RhB), Crystal Violet (CV), Methylene Blue (MB), Methyl Orange (MO), Naphthol Orange (NO) and a phenol derivative, p-Nitrophenol (p-NP). Among them, RhB dye was degraded almost 81 % at 90 min under sunlight irradiation in presence g-C3N4 while other dyes and p-NP was degraded at lower rate. From the experimental data, it was found that MO and p-NP degradation rate was least. The rate constant for degradation of Rh B is 1.1 × 10−2 min−1. Therefore, g-C3N4 can be used as an efficient photocatalyst for waste water treatment by the removal of such organic pollutants.

This research deals with the synthesis of copoly(methylvinyl)(dimethyl)siloxanes by the copolycondensation of dimethyldiethoxy- and methylvinyldimethoxysilane in an active medium, followed by thermal condensation in a vacuum. We achieved a range of copolymers exhibiting finely tuned molecular weights spanning between 1500 and 20,000 with regulated functional methylvinylsiloxane units. Analysis of the microstructure showed that the copolymerization predominantly formed products demonstrating a random distribution of units (R~1). However, an increase in the content of vinyl-containing monomers increases the R parameter, indicating an enhanced tendency towards alternating linkages within the copolymer matrix. [ABSTRACT FROM AUTHOR]

This research deals with the synthesis of copoly(methylvinyl)(dimethyl)siloxanes by the copolycondensation of dimethyldiethoxy- and methylvinyldimethoxysilane in an active medium, followed by thermal condensation in a vacuum. We achieved a range of copolymers exhibiting finely tuned molecular weights spanning between 1500 and 20,000 with regulated functional methylvinylsiloxane units. Analysis of the microstructure showed that the copolymerization predominantly formed products demonstrating a random distribution of units (R~1). However, an increase in the content of vinyl-containing monomers increases the R parameter, indicating an enhanced tendency towards alternating linkages within the copolymer matrix.

Having access to safe drinking water is one of the 17 sustainable development goals defined by the United Nations (UN). However, many settlements around the globe have limited access to drinkable water due to non-anthropogenic pollution of the water sources. One of those pollutants is fluoride, which can induce major health problems. In this manuscript, we report on a post synthetic functionalization of metal organic frameworks for the sensing of fluoride in water. The proposed thermal condensation methodology allows for a high yield of functionalization using few steps, reducing reagent costs and generating minimal by-products. We identified a Rhodamine B functionalized Al-BDC-NH2 metal organic framework as one particularly suitable for fluoride detection in water. [ABSTRACT FROM AUTHOR]

A superficial, one step thermal polycondensation method has been employed for the manifestation of graphene like graphitic carbon nitride (g-C 3 N 4 ) catalyst. The as synthesized g-C 3 N 4 was well characterized by SEM and EDAX analysis, XRD, ATR-IR, FTIR, Fluorescence spectroscopy, Raman spectroscopy and UV-Visible spectroscopy which provide structural, morphological assemblage relating to the structure of g-C 3 N 4 . The g-C 3 N 4 showed that an outstanding photochemical stability, morphology, conductive carbon framework and superior photocatalytic activity. The band gap value of g-C 3 N 4 is 2.34 eV determined using Tauc plot. Due to low band gap (2.33 eV) and unique morphology which provides high separation and migration ability of the photogenerated charges, the g-C 3 N 4 shows enhanced photocatalytic activity for the removal of many organic dyes such as Rhodamine B (RhB), Crystal Violet (CV), Methylene Blue (MB), Methyl Orange (MO), Naphthol Orange (NO) and a phenol derivative, p -Nitrophenol (p-NP). Among them, RhB dye was degraded almost 81 % at 90 min under sunlight irradiation in presence g-C 3 N 4 while other dyes and p-NP was degraded at lower rate. From the experimental data, it was found that MO and p-NP degradation rate was least. The rate constant for degradation of Rh B is 1.1 × 10 -2 min -1 . Therefore, g-C 3 N 4 can be used as an efficient photocatalyst for waste water treatment by the removal of such organic pollutants., Competing Interests: The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Dr. Suranjan Sikdar reports administrative support was provided by University of North Bengal. Afroja Banu reports a relationship with University of North Bengal that includes: non-financial support. N A has patent NA pending to NA. Not Applicable If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors. Published by Elsevier Ltd.)

Having access to safe drinking water is one of the 17 sustainable development goals defined by the United Nations (UN). However, many settlements around the globe have limited access to drinkable water due to non-anthropogenic pollution of the water sources. One of those pollutants is fluoride, which can induce major health problems. In this manuscript, we report on a post synthetic functionalization of metal organic frameworks for the sensing of fluoride in water. The proposed thermal condensation methodology allows for a high yield of functionalization using few steps, reducing reagent costs and generating minimal by-products. We identified a Rhodamine B functionalized Al-BDC-NH2 metal organic framework as one particularly suitable for fluoride detection in water.

Electrochemical energy conversion and storage technologies involving controlled catalysis provide a sustainable way to handle the intermittency of renewable energy sources, as well as to produce green chemicals/fuels in an ecofriendly manner. Core to such technology is the development of efficient electrocatalysts with high activity, selectivity, long-term stability, and low costs. Here, two-dimensional (2D) carbonaceous materials have emerged as promising contenders for advancing the chemistry in electrocatalysis. We review the emerging 2D carbonaceous materials for electrocatalysis, focusing primarily on the fine engineering of active structures through thermal condensation, where the design, fabrication, and mechanism investigations over different types of active moieties are summarized. Interestingly, all the recipes creating two-dimensionality on the carbon products also give specific electrocatalytic functionality, where the special mechanisms favoring 2D growth and their consequences on materials functionality are analyzed. Particularly, the structure-activity relationship between specific heteroatoms/defects and catalytic performance within 2D metal-free electrocatalysts is highlighted. Further, major challenges and opportunities for the practical implementation of 2D carbonaceous materials in electrocatalysis are summarized with the purpose to give future material design guidelines for attaining desirable catalytic structures.

Highlights • For the first time, BCN/NiFe 2 O 4 nanocomposite has been used for the photocatalytic degradation of organic dye. • MB has been used as a model organic dye to study the photocatalytic behavior of synthesized nanomaterials. • The photocatalyst can able to degrade 98% of MB within 80 min under visible light irradiation. • The BCN/NiFe 2 O 4 nanocomposite has enhanced photocatalytic activity towards MB than that of BCN and NiFe 2 O 4. • The as-synthesized nanocomposite photocatalyst had excellent cyclic stability. Abstract In this paper, we report the synthesis of boron doped C 3 N 4 /NiFe 2 O 4 nanocomposite and its application as a visible-light photocatalyst for the degradation of methylene blue (MB). Boron-doped C 3 N 4 (BCN) was prepared by simple thermal condensation of dicyandiamide with boric acid, and NiFe 2 O 4 nanoparticles were prepared by the simple sol-gel method. The as-synthesized nanocomposite materials were characterized and confirmed by the X-ray diffraction spectroscopy, Fourier-transform infrared spectroscopy, field-emission scanning electron microscopy, transmission electron microscopy, UV–Visible diffuse reflectance spectroscopy, X-ray photoelectron spectroscopy, and photoluminescence spectroscopy. The photocatalytic activity of BCN/NiFe 2 O 4 nanocomposite was evaluated towards the degradation of MB in the presence of visible light irradiation. The obtained results confirmed that BCN/NiFe 2 O 4 composite has higher degradation efficiency (98%) than that of BCN and NiFe 2 O 4. [ABSTRACT FROM AUTHOR]

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In this paper, a novel thermal condensation method was developed for preparing mesoporous g-C 3 N 4 /TiO 2 composite by using PAA-Ti/TiO 2 and melamine as co-precursors. This method can not only ensure the incorporation of TiO 2 nanoparticles into g-C 3 N 4 matrix but also lead to the formation of mesoporous structures. In the heating process, polyacrylate (PAA) in the PAA-Ti/TiO 2 composites can volatilize to produce carbonous gases and its volatilization temperature falls into the temperature range for melamine condensation, which makes PAA-Ti/TiO 2 a suitable pore-forming agent for fabricating mesoporous g-C 3 N 4 /TiO 2 . The largest surface area for the fabricated mesoporous g-C 3 N 4 /TiO 2 was found to be 268 m 2 g −1 , which was approximately 7 or 12 times higher than that of TiO 2 or g-C 3 N 4 . The mesoporous g-C 3 N 4 /TiO 2 composite exhibited excellent reproducibility and good performance in the photocatalytic decomposition of dinitro butyl phenol (DNBP) under visible-light illumination. The enhanced photocatalytic efficiency can be attributed to the synergetic effects of large surface area and the formation of heterojunction interface between g-C 3 N 4 and TiO 2 . [ABSTRACT FROM AUTHOR]

The present work deals with synthesis of 2-Pyridyl - 4 Quinazolone (NN) (A1), 2-Pyrazinyl - 4 - Quinazolone (A2).The synthesis is based on Niementowski Reaction which involves condensation of the reactants under varying thermal conditions. The synthesis of 2-hetero substituted Quinazolone is based on Niementowski Reaction involves thermal condensation and cyclisation of a drug amide and Anthranilic acid / 3, 5 di bromo anthranilic acids at elevated temperatures to yield the various hetero-moieties. The drug amides used are Nicotinamide, Pyrazinamide and Carbamezepine. The products formed were recrystallized using ethanol. Thin layer chromatography was carried out using Benzene: ethanol. The melting points of the products were found by capillary tube method. The values are uncorrected. The synthesized compounds have been characterized using UV, IR, NMR and MASS. The literature review indicates that Substituted Quinazolinones have wide spectrum of pharmacological activity such as anti-bacterial, antimicrobial, antiviral and antifungal. Hence antimicrobial study was carried out. The antibacterial activity of the synthesized compounds was determined .The pathogens used in this study included both gram positive and gram negative organisms. Namely Negative coagulase staphylococci, Staphylococcus aureus, Escherichia coli, Klebsiella pneumonia, all the synthesized compounds showed antibacterial activity to varying degree against the organisms tested. Zone of inhibition was carried out using Antibiotic disc diffusion assay method Amikacin (5μg/ml) was used as control. [ABSTRACT FROM AUTHOR]

The frequent use of methylene blue (MB) and other organic dyes pose serious environmental concerns subjected to their resistance towards traditional degradation procedures. Therefore, it is important to develop efficient degradation treatments to degrade such dyes. We report a facile thermal condensation methodology to synthesize graphitic nitride (GN) and its derived polyimides by using three different dianhydrides. The obtained results from physicochemical characterization; FTIR, XRD, XPS, and BET/BJH confirmed the formation of GN and its derived polyimides. The synthesized photocatalyst materials were tested for MB degradation under light irradiation for 60 min. Interestingly, the superior photocatalytic performance (96% MB degradation efficiency) despite of decreased surface area of polyimide, GN-FDA (6.78 m2 g−1) has been attributed to its relatively improved degree of crystallinity, greater HOMO-LUMO charge separation, high quaternary nitrogen content, and appropriate porosity. This study can be concluded as follows; firstly the π conjugated polyimides surprisingly undergo significant shrinkage in surface area probably due to π-π interactions. Secondly, derived polyimides exhibited essential features of photocatalytic materials viz greater HOMO-LUMO charge separation evidenced by DFT studies, improved hydrophilicity, appropriate surface area/ porosity, and surface nitrogen functionalities that improve their degradation efficiency. Quantum mechanical calculations reveal that modification of GN results in improved electronic properties and enhanced dye degradation attributed to modified charge transfer. This work may open new opportunities to develop efficient metal-free photocatalysts based on GN that are a significant contribution in designing suitable photocatalyst materials for degradation of other organic dyes/ contaminants. [Display omitted] • Graphitic Nitride (GN) based polyimides were synthesized by thermal condensation of derived GN with different dianhydrides. • The polyimides were characterized by physicochemical techniques; FTIR, XRD, BET/BJH, XPS, SEM, UV-vis and PL spectroscopy. • The synthesized polyimide; GN-FDA exhibited highest degradation efficiency (96 %) for the degradation of methylene blue dye. • Quantum mechanical calculations suggested improved electronic properties and modified charge transfer in the polyimides. • The improved physicochemical properties and modified charge transfer resulted in high degradation efficiency of polyimide. [ABSTRACT FROM AUTHOR]

Green copolymer Poly(MA-CA) was developed by the thermal condensation polymerization of monomers such as DL-Malic acid (MA) and Citric acid (CA). The copolymer of Poly(MA-CA) was synthesized by varying the ratio of MA and CA monomers with 1:0, 1:3, 1:1, 3:1 and 0:1, and their antibacterial properties were studied with respect to their activity onGram-positiveandGram-negativebacteria by the bacterial count method. Furthermore, the biocidal activity of the plain monomers was also investigated and compared to those of the copolymers. Synthesized copolymers show good antibacterial effects towards bothGram-positiveandGram-negativebacteria. The antimicrobial properties of the copolymers and the monomers were studied by varying the ratio of polymers, effect of polymer concentration and effect of pH. Results indicated that the antibacterial activity of the copolymers increased with MA content and polymer dose. At low content of MA (wt.%), the copolymers poly(MA-CA)(1:3) possessed a higher effect onGram-positivebacteriaBacillus cereus and Micrococcus luteusthanGram-negativebacteriaSalmonella and Shigella. The other copolymers with the ratio of 1:1 and 3:1 including MA homopolymer possesses 100% inhibition of both Gram-positive and Gram-negative bacteria under the conditions studied. The developed polymers were extensively characterized by Fourier transform infrared spectroscopy analysis, thermal gravimetric analysis, X-ray diffraction analysis and scanning electron microscope-energy dispersive spectroscopy to understand their physicochemical properties. [ABSTRACT FROM AUTHOR]

Creating materials that are capable of catalyzing enzymatic reactions could be important to the treatment of both acute and chronic wounds, as well as other topical diseases. As a first step in the design of catalytic biomaterials, a new class of proteinoid microsphere (PM), that includes amino acids found in phosphatase enzyme active sites, has been constructed. This material can significantly enhance catalytic activity for phosphoester hydrolysis, with observed specific activity increases between 35- and 55-fold. Further specific activity increases occur when metal cations, notably iron or zinc, are added to the PMs. Specific activity increases between 140- and 300-fold for these metal modified systems are measured. The phosphatase activity increase is demonstrated for both aromatic phosphate esters as well as the high-energy phosphate bond of adenosine triphosphate. PMs bind substrate heterogeneously on their surfaces in an enthalpically driven reaction that is defined by an overall favorable free energy, but unfavorable entropy. The catalytic PMs have been successfully blended with polyolefin foam and extruded with PLA. These materials remain fully active. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013. [ABSTRACT FROM AUTHOR]

A study of the synthesis of a 4-hydroxyquinoline derivative using the Conrad-Limpach reaction led to the identification of inexpensive and user-friendly solvents for this thermal condensation. [ABSTRACT FROM AUTHOR]

It is widely held that there was a phosphate compound in prebiotic chemistry that played the role of adenosine triphosphate and that the first living organisms had ribose-phosphate in the backbone of their genetic material. However, there are no known efficient prebiotic synthesis of high-energy phosphates or phosphate esters. We review the occurrence of phosphates in Nature, the efficiency of the volcanic synthesis of PO, the efficiency of polyphosphate synthesis by heating phosphate minerals under geological conditions, and the use of high-energy organic compounds such as cyanamide or hydrogen cyanide. These are shown to be inefficient processes especially when the hydrolysis of the polyphosphates is taken into account. For example, if a whole atmosphere of methane or carbon monoxide were converted to cyanide which somehow synthesized polyphosphates quantitatively, the polyphosphate concentration in the ocean would still have been insignificant. We also attempted to find more efficient high-energy polymerizing agents by spark discharge syntheses, but without success. There may still be undiscovered robust prebiotic syntheses of polyphosphates, or mechanisms for concentrating them, but we conclude that phosphate esters may not have been constituents of the first genetic material. Phosphoanhydrides are also unlikely as prebiotic energy sources. [ABSTRACT FROM AUTHOR]

Colon cancer is one of the major causes of death in the Western world. Early detection significantly improves long-term survival for patients with colon cancer. Near-infrared (NIR) fluorescent nanoparticles are promising candidates for use as contrast agents for tumor detection. Using NIR offers several advantages for bioimaging compared with fluorescence in the visible spectrum: lower autofluorescence of biological tissues and lower absorbance and, consequently, deeper penetration into biomatrices. The present study describes the preparation of new NIR fluorescent proteinoid-poly(L-lactic acid) (PLLA) nanoparticles. For this purpose, a P(EF-PLLA) random copolymer was prepared by thermal copolymerization of L-glutamic acid (E) with L-phenylalanine (F) and PLLA. Under suitable conditions, this proteinoid-PLLA copolymer can self-assemble to nanosized hollow particles of relatively narrow size distribution. This self-assembly process was used for encapsulation of the NIR dye indocyanine green. The encapsulation process increases significantly the photostability of the dye. These NIR fluorescent nanoparticles were found to be stable and nontoxic. Leakage of the NIR dye from these nanoparticles into phosphate-buffered saline containing 4% human serum albumin was not detected. Tumor-targeting ligands such as peanut agglutinin and anticarcinoembryonic antigen antibodies were covalently conjugated to the surface of the NIR fluorescent P(EF-PLLA) nanoparticles, thereby increasing the fluorescent signal of tumors with upregulated corresponding receptors. Specific colon tumor detection by the NIR fluorescent P(EF-PLLA) nanoparticles was demonstrated in a chicken embryo model. In future work, we plan to extend this study to a mouse model, as well as to encapsulate a cancer drug such as doxorubicin within these nanoparticles for therapeutic applications.