Carbonyl Functional Groups Research Articles

A non-fullerene acceptor as an interfacial modified layer for enhancing efficiency and stability of inverted perovskite solar cells

The molecular structure of INDCDT-b8-Cl, which is rich in carbonyl and cyano functional groups, is used as an interfacial modified layer for PSCs.

Biosynthesis of Poly Acrylic Acid (PAA) Modified Silver Nanoparticles, Using Basil Leaf Extract (Ocimum basilicum L.) for Heavy Metal Detection

<p>This study focused on characterizing synthesized silver nanoparticles (AgNPs) and evaluating their efficacy as colorimetric detectors for heavy metal ions. The synthesis employed a bottom-up approach, using AgNO<sub>3</sub> as a precursor, reduced by secondary metabolites in basil leaf extract, enhanced with Polyacrylic acid (PAA). Basil leaves were chosen for their rich content of secondary metabolites like phytosterols, alkaloids, phenolic compounds, tannins, lignin, starch, saponins, flavonoids, terpenoids, and anthraquinones, crucial in reducing silver ions. Incorporating basil leaf extract as a bioreactor and adding PAA to increase stability and selectivity towards metal ions are innovative aspects of this research. The optimal AgNP composition was attained with a 0.7 mL basil leaf extract to 10 mL AgNO<sub>3</sub> ratio plus 2% PAA. The AgNP formation was indicated by a color change from yellow to brownish, with a Surface Plasmon Resonance (SPR) peak at 418 nm. Characterization via Fourier Transform Infrared Spectroscopy (FTIR) revealed hydroxyl (-OH) and carbonyl (C=O) functional groups aiding in silver ion reduction. Particle Size Analysis (PSA) showed AgNPs of 72.3 nm size, with a polydispersity index of 0.504. Colorimetric detection tests were conducted on Cu(II), Pb(II), Cd(II), Zn(II), and Mn(II) ions. AgNPs exhibited high reactivity towards Cu<sup>2+</sup>, changing color from brownish to clear white within a minute upon Cu2+ addition, unlike Cd<sup>2+</sup>, Mn<sup>2+</sup>, Zn<sup>2+</sup>, and Pb<sup>2+</sup>, which showed negligible changes. This indicates a heightened sensitivity of AgNPs to Cu<sup>2+</sup> ions. Such a colorimetric sensor could be instrumental in detecting heavy metals in drinking water, showcasing the potential application of AgNPs in environmental monitoring.</p>

Effective adsorptive removal of a cationic dye from aqueous solutions using a biosorbent derived from Sargassum sp.

Abstract The present research evaluated the potential use of the macroalga Sargassum sp., which was modified with filamentous fungus Cunninghamella echinulata for the biosorption of methylene blue (MB) dye. The modified fungal biomass (FERsarg) was obtained through solid-state fermentation of enzyme (alginate lyase). The FERsarg showed a pHPZC of 7.9, a low mass loss, material micro/mesoporous, and the presence of hydroxyl, carboxylic, phenolic, and carbonyl functional groups. The influence of biomass dosage, solution pH, contact time, initial concentration, and temperature were evaluated for MB biosorption, and the best results were obtained at 2 g L-1 and pH 6. The kinetic study revealed a better fit for the pseudo-second-order model, while the Sips model best described the equilibrium experimental data. The equilibrium was reached within 180 min and showed qmax yielding of 115.49 mg g-1 at 323 K. The thermodynamic understanding of the present research revealed that the biosorbent exhibited spontaneous, exothermic, and physical nature for MB removal. The adsorptive mechanism shows that the process was controlled by electrostatic attraction. Also the feasibility of using residual fermented biomass as a potential adsorbent was applied and discussed, contributing to the concept of minimum waste generation, and supporting the concept of circular bioeconomy.

Mechanism of Infiltration between Alumina and Polyurea for Stretchable Patterned Thin Film

Conventional display panels could be replaced by OLED displays, which are a leading and popular technology in display industry. While OLEDs are quite stretchable, they are vulnerable to oxygen and moisture, and currently, there is no proper barrier film that can protect them from these elements while also maintaining high stretchability. In this study, a horizontally patterned organic/inorganic layer that can increase the stretchability of the film while also providing the necessary protection is proposed. The final structure of the thin film will consist of two layers: a stripe-patterned organic/inorganic layer created using area-selective ALD/MLD processes, followed by an organic layer.To achieve the research objectives, the degree of infiltration of the inorganic layer into the organic layer is crucial. In this study, the mechanism behind the generation of the interface layer between alumina and polyurea is investigated. Trimethylaluminum (TMA) and H2O were used as precursors for fabricating alumina by ALD, while 1,4-phenylene diisocyanate (PPDI) and ethylene diamine (ED) were used for fabricating polyurea by MLD. The porous structure of the polymer allows ALD precursors to spread into it. During TMA pulsing on the polymer layer, the degree of infiltration is affected by the type of chemical bond in the polymer. Previous research has shown that TMA precursors are more likely to infiltrate polymers with C=O bonds into the polymer layer. Therefore, polyurea, which contains a carbonyl functional group (-C(=O)-), is suitable for this research. While the conditions for polyurea MLD are fixed, five chamber temperature conditions for depositing alumina were selected: 30℃, 50℃, 70℃, 90℃, and 110℃. Alumina was deposited by ALD on 30nm of polyurea which was deposited on a Si wafer.From X-ray reflectivity (XRR) data, it was observed that three main types of thin films were formed. As the temperature increased, the density and thickness of the alumina layer forming the thin film changed. To verify the change in the alumina thin film, FTIR and XPS were used to compare the peaks representing the bonds of Aluminum and Oxygen.

An Efficient Synthesis of 1-(1,3-Dioxoisoindolin-2-yl)-3-aryl Urea Analogs as Anticancer and Antioxidant Agents: An Insight into Experimental and In Silico Studies.

The present investigation reports the efficient multistep synthesis of 1-(1,3-dioxoisoindolin-2-yl)-3-aryl urea analogs (7a-f) in good yields. All the 1-(1,3-dioxoisoindolin-2-yl)-3-aryl urea analogs (7a-f) were characterized by spectroscopic techniques. Five among the six compounds were tested against 56 cancer cell lines at 10 µM as per the standard protocol. 1-(4-Bromophenyl)-3-(1,3-dioxoisoindolin-2-yl)urea (7c) exhibited moderate but significant anticancer activity against EKVX, CAKI-1, UACC-62, MCF7, LOX IMVI, and ACHN with percentage growth inhibitions (PGIs) of 75.46, 78.52, 80.81, 83.48, 84.52, and 89.61, respectively. Compound 7c was found to exhibit better anticancer activity than thalidomide against non-small cell lung, CNS, melanoma, renal, prostate, and breast cancer cell lines. It was also found to exhibit superior anticancer activity against melanoma cancer compared to imatinib. Among the tested compounds, the 4-bromosubstitution (7c) on the phenyl ring demonstrated good anticancer activity. Docking scores ranging from -6.363 to -7.565 kcal/mol were observed in the docking studies against the molecular target EGFR. The ligand 7c displayed an efficient binding against the EGFR with a docking score of -7.558 kcal/mol and displayed an H-bond interaction with Lys745 and the carbonyl functional group. Compound 7c demonstrated a moderate inhibition of EGFR with an IC50 of 42.91 ± 0.80 nM, in comparison to erlotinib (IC50 = 26.85 ± 0.72 nM), the standard drug. The antioxidant potential was also calculated for the compounds (7a-f), which exhibited good to low activity. 1-(2-Methoxyphenyl)-3-(1,3-dioxoisoindolin-2-yl)urea (7f) and 1-(4-Methoxyphenyl)-3-(1,3-dioxoisoindolin-2-yl)urea (7d) demonstrated significant antioxidant activity with IC50 values of 15.99 ± 0.10 and 16.05 ± 0.15 µM, respectively. The 2- and 4-methoxysubstitutions on the N-phenyl ring showed good antioxidant activity among the series of compounds (7a-f). An in silico ADMET prediction studies showed the compounds' adherence to Lipinski's rule of five: they were free from toxicities, including mutagenicity, cytotoxicity, and immunotoxicity, but not for hepatotoxicity. The toxicity prediction demonstrated LD50 values between 1000 and 5000 mg/Kg, putting the compounds either in class IV or class V toxicity classes. Our findings might create opportunities for more advancements in cancer therapeutics.

Sorption kinetics of heavy metals from aqueous solution using Spirogyra sp.: a microcosm study

Understanding the mechanisms by which algae communities respond to disturbances in the lotic aquatic environment that is polluted by heavy metals is important, considering that algae is a biotic component of waters that acts as a producer in the aquatic food chain which has the potential to bio-magnify. This study examines the influence of time, biomass weight, heavy metal concentration, sorption capacity, and efficient removal on epilithic periphyton as a bio-accumulator of Cr, Pb, and Ni. The experiment was conducted on a laboratory scale using a canal system with a length and width of 1.2 and 1.0 meters, respectively. The canal system contains 132 L of water, has a 1.2 m2 substrate and periphyton area, a depth of 0.09 – 0.10 m, and a current flow rate of 0.04 – 0.06 m/s. The dissolved Cr6+ initial concentration in the medium was 1.64 mg/L, Pb2+ and Ni2+ concentrations were 1.4 mg/L, and the adsorption process was studied for 24 hours. Based on microscope observations and functional group interpretation utilizing infrared spectra (FTIR), the periphyton community is dominated by Spirogyra sp., which has hydroxyl (O-H), carboxyl (C-H), and carbonyl (C-C and C=O) functional groups with the ability to binding heavy metals. The remaining quantities of Cr, Pb, and Ni in water were 0.43 mg/L (removal 69.29%), 0.05 mg/L (96.43% removal), and 0.03 mg/L (97.86% removal). Periphyton has a maximal sorption capacity of 1.019 mg Cr/g, 1.97 mg Pb/g, and 1.92 mg Ni/g. The sorption kinetics of Cr, Pb, and Ni follow a pseudo-second-order model with k2 = 1.686 x 10-2 g/mg.min for Cr, 4.516 x 10-3 g/mg.min for Pb, and 2.259 x 10-2 g/mg.min for Ni, with R2 of 0.965 for Cr and 0.971 for Pb and 0.972 for Ni. Periphyton can potentially play a role as a bio-accumulator in lotic habitats, adsorbing Cr, Pb, and Ni ions, according to this study.

Three‐dimensional Polymers as Organic Cathodes for Affordable and Sustainable Sodium/Potassium‐ion Batteries

AbstractRedox‐active polymers (RAPs) are promising organic electrode materials for affordable and sustainable batteries due to their flexible chemical structures and negligible solubility in the electrolyte. Developing high‐dimensional RAPs with porous structures and crosslinkers can further improve their stability and redox capability by reducing the solubility and enhancing reaction kinetics. This work reports two three‐dimensional (3D) RAPs as stable organic cathodes in Na‐ion batteries (NIBs) and K‐ion batteries (KIBs). Carbonyl functional groups are incorporated into the repeating units of the RAPs by the polycondensation of Tetrakis(4‐aminophenyl)methane and two different dianhydrides. The RAPs with interconnected 3D extended conjugation structures undergo multi‐electron redox reactions and exhibit high performance in both NIBs and KIBs in terms of long cycle life (up to 8000 cycles) and fast charging capability (up to 2 A g−1). The results demonstrate that developing 3D RAPs is an effective strategy to achieve high‐performance, affordable, and sustainable NIBs and KIBs.

Transformation of 5-hydroxymethylfurfural to 5-hydroxymethyl-2-furan carboxylic acid mediated by silver nanoparticles biosynthesized from Spartium junceum flower extract

The central idea of this study is to develop a green, efficient, and simple method for producing silver nanoparticles (Ag NPs) using Spartium junceum flower extract. The extract contains phenolic hydroxyl and carbonyl functional groups that enhance the adsorption of silver ions and their subsequent reduction to Ag NPs in situ. The synthesis of Ag NPs using this method offers a new environmentally friendly approach that the prepared nanoparticles exhibit high catalytic activity in the conversion of 5-hydroxymethylfurfural (5-HMF) into the more valuable chemical 5-Hydroxymethyl-2-furan carboxylic acid (HMFCA). The study investigates the parameters for HMFCA synthesis, including solvent, reaction temperature, reaction time, catalyst amount, base, and oxidant, using Ag NPs. The Ag NPs was characterized by various techniques such as FESEM, XRD, TEM, UV–Vis, and DLS. The results demonstrated that under optimal conditions, a yield of 98 % for HMFCA and a conversion rate of 99 % for 5-HMF were achieved at a temperature of 40 °C and a reaction time of 1 h. Furthermore, our catalytic system exhibited the ability to be reused for at least 12 cycles.

Unveiling microplastic spectral signatures under weathering and digestive environments through shortwave infrared hyperspectral sensing

Microplastic (MP) pollution presents a novel challenge for marine environmental protection, necessitating comprehensive and long-term monitoring and assessment approaches. Environmental MPs can undergo weathering and microorganism-related digestive processes, altering their original surface properties and chemical structure, thus complicating their quantification and identification. This study aims to establish a comprehensive hyperspectral database for weathered and digestion-degraded MPs, using a wide variety of polymer types collected as either virgin particles or commercial products (within a size range of approximately 3 mm), and to investigate the impact of these processes on their spectral characteristics. Polypropylene (PP) and polyethylene (PE) MPs exhibited significant responses to weathering treatment, as indicated by the formation of new characteristic peaks or slight peak shifts around 1679–1705 nm, which can be attributed to the formation of carbonyl and vinyl functional groups through Norrish reactions. Similarly, polyethylene terephthalate (PET), acrylonitrile butadiene styrene (ABS), and polystyrene (PS) MPs demonstrated notable degradation following digestive treatment, as evidenced by the emergence of new absorption peaks at approximately 1135–1165 nm, possibly associated with alterations involving carbonyl and vinyl functional groups. The results were further validated based on their comparable spectral characteristics of the resultant MPs to reference polymers and possible additives, considering a reasonably accurate match of approximately 80% for the studied MP samples. This study showcases the significant advantage of using shortwave infrared hyperspectral sensing for rapid identification of virgin and exposed MPs with a relatively large scan area after a simple sample preparation. This approach, combined with other complementary characterization techniques, shall provide highly throughput results for MPs identification. This research provides valuable insights into the features extracted from environmental MPs and establishes a foundation for improving their classification efficiency for environmental applications.

Synthesis, characterization, and thermal decomposition performance of 1,2,3-triazolyl-substituted 1,3,5-triazines with carbonyl, ester, and azide functional groups

Based on the organocatalytic reaction of enamine azide addition of 2,4,6-triazido-1,3,5-triazine to acetylacetone acetoacetic ester, we synthesized a series of previously unknown mono-, di-, and tri(1,2,3-triazolyl)-substituted-1,3,5-triazines that additionally carried carbonyl, ester, and azide groups. The structure of the obtained compounds was proved by NMR (1H, 13C) and IR spectroscopy, and the composition was confirmed by elemental analysis. With the aid of differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) coupled to mass spectrometry (TG-MS), we obtained data on the thermal behavior and decomposition mechanism for these compounds. We demonstrated that di(1,2,3-triazolyl)-substituted 1,3,5-triazines have an increased thermal stability and have higher values of decomposition onset temperature (220–250 °C) in comparison with tri(1,2,3-triazolyl)-substituted 1,3,5-triazines (180 °C and 160 °C, respectively).

Significant Efficiency and Stability Enhancement of Flexible Perovskite Solar Cells Combining with Multifunctional Effects of a Natural Spice

AbstractThe numerous defect‐induced non‐radiative recombination losses and residual stress in the preparation of perovskite film greatly hinder the further improvement of the efficiency and stability of flexible perovskite solar cells (PSCs). Here, a natural spice 7‐amino‐4‐(trifluoromethyl)‐2‐benzopyrone (ATB) containing amino (─NH2), carbonyl (─C═O), and trifluoromethyl (─CF3) functional groups is introduced into the perovskite precursor solution, thereby preparing high‐quality perovskite film with low defect density. It is revealed that the utilization of ATB is beneficial to comprehensively passivate the defects and release the residual stress of perovskite film through the synergistic effect of functional groups, thereby improving the crystallinity and enhancing the carrier lifetime of perovskite film. Moreover, the introduction of ATB contributes to an improved energy levels alignment between the perovskite and adjacent layers, which facilitates fast carrier transport and suppresses the recombination loss in the flexible PSCs. Combined with the multifunctional effects of ATB, the target flexible and rigid PSCs with ATB modification yield remarkable photoelectric conversion efficiency (PCE) of 21.08% and 23.79%, respectively. More importantly, the ATB‐modified flexible device exhibits outstanding stability and retains 87.3% and 91.6% of the original efficiency after aging for 3000 h at 50 ± 5 relative humidity and 5000 bending cycles, respectively.

Antibiotic-Powered Energy Harvesting: Introducing Benzylpenicillin as an Efficient Tribopositive Material for Triboelectric Nanogenerators

The pursuit of enhancing the performance of triboelectric nanogenerators (TENGs) has led to the exploration of new materials with efficient charge-generating capabilities. Herein, we propose benzylpenicillin sodium salt (b-PEN) as a candidate biomaterial for the tribopositive layer owing to its superior electron-donating capability via the lone pairs of electrons on its sulfur atom, carbonyl, and amino functional groups. The proposed b-PEN TENG device exhibits promising electrical performance with an open-circuit voltage of 185 V, a short-circuit current of 4.52 µA, and a maximum power density of 72 µW/cm2 under force applied by a pneumatic air cylinder at 5 Hz. The biomechanical energy-harvesting capabilities of the b-PEN TENG device are demonstrated by actuating it with finger, hand, and foot movements. Moreover, the proposed TENG device is utilized to charge capacitors and power light-emitting diodes by scavenging the externally applied mechanical energy. This outstanding electrical performance makes b-PEN a promising tribopositive material.

X-ray quantification of oxygen groups on diamond surfaces for quantum applications

Identifying the surface chemistry of diamond materials is increasingly important for device applications, especially quantum sensors. Oxygen-related termination species are widely used because they are naturally abundant, chemically stable, and compatible with stable nitrogen vacancy centres near the diamond surface. Diamond surfaces host a mixture of oxygen-related species, and the precise chemistry and relative coverage of different species can lead to dramatically different electronic properties, with direct consequences for near-surface quantum sensors. However, it is challenging to unambiguously identify the different groups or quantify the relative surface coverage. Here we show that a combination of x-ray absorption and photoelectron spectroscopies can be used to quantitatively identify the coverage of carbonyl functional groups on the diamond surface. Using this method we reveal an unexpectedly high fraction of carbonyl groups (9%) on a wide range of sample surfaces. Furthermore, through a combination of ab initio calculations and spectroscopic studies of engineered surfaces, we reveal unexpected complexities in the x-ray spectroscopy of oxygen terminated diamond surfaces. Of particular note, we find the binding energies of carbonyl-related groups on diamond differs significantly from other organic systems, likely resulting in previous misestimation of carbonyl fractions on diamond surfaces.

Carbonaceous adsorbent as green silica by-product applied to the treatment of contaminated effluent by pesticide commonly sprayed on rice cultivation.

Grain cultivation and its impacts on the environment have been the focus of many studies, especially due to generated solid waste and the wide use of agrochemicals aiming for greater productivity. In this context, the present study proposes a new and consistent step in constructing self-sustainability in rice farming. The proposed stage includes reusing green silica waste as an adsorbent to treat effluents contaminated by pesticides directly applied to rice cultivation. After nano silica production through the rice husks burning, followed by basic leaching and acid precipitation, a carbonaceous material remains. This material, naturally impregnated by Na2SiO3, was washed and dried, characterized, and used to remove the pesticide 2,4-dichlorophenoxyacetic acid (2,4-D). The adsorption essays were performed at 2,4-D at low concentrations (between 1 and 10mg L-1) at different temperatures. The washed and dried porous carbon (WDPC) surface is irregular and presents slit-shaped channels. The FT-IR analysis identified the siloxane, carbonyl, carboxylate, and methylene functional groups available to interact with the pesticide molecules. The washing/drying process eliminated impurities, improving the surface area from 539.67 to 619.67 cm2g-1 and pore volume from 0.29 to 0.44 cm3g-1. Concerning the adsorption of 2,4-D on WDPC, the best pH was 6.0, where around 75% of the pesticide was removed from the water. The equilibrium isotherms presented an S-shaped form indicating a multilayer and cooperative adsorption, with maximum adsorption capacities of 7.504 and 7.736mgg-1. The estimated ∆Gads, ΔHads, and ΔSads values suggested that pesticide adsorption was spontaneous, exothermic, and favorable. Finally, WDPC demonstrated a good potential to uptake 2,4-D from water, contributing to self-sustainability in rice farming.

Green synthesis of Ag/CuO and Ag/ [formula omitted] nanoparticles for enhanced photocatalytic dye degradation, antibacterial, and antifungal properties

In the context of synthesizing metal doped metal oxide nanoparticles (NPs), green synthesis emerges as a reliable, sustainable, environmentally-friendly, and exceptional alternative to the more efficient and conventional chemical methods. In this study, we explored the co-precipitation method performed for the Caesalpinia pulcherrima (C.pulcherrima) flower extract high percentage of hydroxyl functional groups on terpenoid derivatives, reducing and encapsulating agents, and the stability of the Ag/CuO and Ag/ TiO2 NPs. The XRD patterns provided evidence of the highly crystalline structure of monoclinic CuO, tetragonal crystal structure, and face-centered cubic Ag metal, obtained to improve the nanosized 6 and 8 nm, which structural defects in the synthesis materials were determined by scanning and transmission electron microscopy (SEM and TEM), as well as by X-ray photoelectron spectroscopy (XPS) and energy-dispersive X-ray spectroscopy (EDX) analyze. The existence of Ag ions (Ag+), Ti4+ ions, and Cu2+ ions in CuO and TiO2 caused the reduction of carbonyl and hydroxide functional groups, thereby facilitating the efficient formation of nanostructures, as demonstrated by XPS and Fourier transform infrared spectroscopy (FTIR). The band gap analysis of Ag/CuO and Ag/TiO2 NPs revealed that they increased the catalytic activity of methylene blue (MB) dye degradation efficiency achieved by 86 and 94 %, respectively. Comparatively, Ag doped with CuO and TiO2 has a synergistic effect leading to in highly effective antimicrobial activity against P. aeruginosa and E. coli infections.

Spectroscopic analysis of 1.75 MeV N5+ ions irradiated polystyrene film and the quest for the reaction mechanisms of fullerene and other products

The effects of 1.75 MeV N5+ ion beams of varying fluences, ranging from 1 × 1011 to 1 × 1014 ions/cm2, have been used to investigate the structural, optical, and chemical properties of polystyrene using X-ray diffraction (XRD), UV–Visible spectroscopic, and Fourier transform infrared (FTIR) spectroscopic techniques. The changes in polystyrene polymer depend on ion fluence. The crystallinity has been increased drastically up to the ion fluence of 5 × 1012 ions/cm2, and decreases further up to 1 × 1014 ions/cm2. The energy of the direct bandgap is found to be reduced by up to 50% when compared to the pristine one. The shift in absorption maxima towards a higher wavelength supports color development in polymer films and is due to the formation of extended conjugation. The developments of FTIR peaks at 1601, 1697, 3321, and 3723 cm−1 support the existence of aromatic rings, carbonyl (>CO), acetylenic (-CC-), and hydroxyl functional groups in the irradiated polystyrene. Functional group generation is exponentially dependent on the quantity of ion fluences. The reaction mechanism of degradation products formation chemistry has been discussed.

Abraham general solvation parameter model: intramolecular hydrogen bond formation and its effect on the A- and B-descriptor values of select tetracycline derivatives

ABSTRACT Experiment-based Abraham model solute descriptors are calculated from published solubility data for sancycline dissolved in methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-methyl-1-propanol, 1-octanol, cyclohexane, acetonitrile, ethyl acetate and 1,4-dioxane at 298.15 K. The calculated descriptor values suggest that sancycline engages in strong intramolecular hydrogen formation. The hydrogen-bond acidity and basicity solute descriptor values obtained from the experimental solubility data are considerably smaller than what would be expected based on the four hydroxyl, one amide, one dimethylamino and two carbonyl functional groups contained in the molecule. Our study further shows that existing group contribution and machine learning methods provide rather poor estimates of the experiment-based solute descriptors of sancycline.

Carbonyl-Supported Coordination in Imidazolates: A Platform for Designing Porous Nickel-Based ZIFs as Heterogeneous Catalysts.

Zeolitic imidazolate frameworks (ZIFs) are a subclass of metal-organic framework that have attracted considerable attention as potential functional materials due to their high chemical stability and ease of synthesis. ZIFs are usually composed of zinc ions coordinated with imidazole linkers, with some other transition metals, such as Cu(II) and Co(II), also showing potential as ZIF-forming cations. Despite the importance of nickel in catalysis, no Ni-based ZIF with permanent porosity is yet reported. It is found that the presence and arrangement of the carbonyl functional groups on the imidazole linker play a crucial role in completing the preferred octahedral coordination of nickel, revealing a promising platform for the rational design of Ni-based ZIFs for a wide range of catalytic applications. Herein, the synthesis of the first Ni-based ZIFs is reported and their high potential as heterogeneous catalysts for Suzuki-Miyaura cross-coupling C─C bond forming reactions is demonstrated.

One-pot hydrothermal green synthetic approach of fluorescent carbon dots as optical probes for 2-nitrophenol

The pursuit of a cost-effective and green synthetic approach to chemical sensors and their application in the sensing of toxic and harmful substances is a never-ending exercise for scientists and researchers. Preparation of fluorescent carbon dots (C-dots) from biomass using water as a solvent and a hydrothermal autoclave to provide the required synthesis temperature offers a cheap and environmentally friendly synthetic approach. Herein, we report a faster, less costly and ecofriendly hydrothermal synthetic approach of carbon dots from Citrullus vulgaris peels as a precursor. The as-prepared carbon dots exhibited hydroxyl, carbonyl and amide functional groups on the surface and an amorphous structure with a particle size distribution of 1.7–3.0 nm. Moreover, the carbon dots displayed intense blue emission fluorescence at 470 nm after excitation at 400 nm. The as-prepared carbon dots demonstrated effective application without further modification towards the selective and sensitive optical recognition of 2-nitrophenol used in the manufacture of explosives. A limit of detection of 2.28×10−7 M was achieved, and no fluorescence quenching was observed in the presence of other nitroaromatic and benzene derivatives indicating excellent selectivity towards 2-nitrophenol. Finally, further studies are required to investigate the potential for the as-prepared carbon dots to monitor nitroaromatic pollutants in real environmental systems.

Latest Advancements in the Development of High-Performance Lignin- and Tannin-Based Non-Isocyanate Polyurethane Adhesive for Wood Composites.

The depletion of natural resources and increasing environmental apprehension regarding the reduction of harmful isocyanates employed in manufacturing polyurethanes (PUs) have generated significant attention from both industrial and academic sectors. This attention is focused on advancing bio-based non-isocyanate polyurethane (NIPU) resins as viable and sustainable substitutes, possessing satisfactory properties. This review presents a comprehensive analysis of the progress made in developing bio-based NIPU polymers for wood adhesive applications. The main aim of this paper is to conduct a comprehensive analysis of the latest advancements in the production of high-performance bio-based NIPU resins derived from lignin and tannin for wood composites. A comprehensive evaluation was conducted on scholarly publications retrieved from the Scopus database, encompassing the period from January 2010 to April 2023. In NIPU adhesive manufacturing, the exploration of substitute materials for isocyanates is imperative, due to their inherent toxicity, high cost, and limited availability. The process of demethylation and carbonation of lignin and tannin has the potential to produce polyphenolic compounds that possess hydroxyl and carbonyl functional groups. Bio-based NIPUs can be synthesized through the reaction involving diamine molecules. Previous studies have provided evidence indicating that NIPUs derived from lignin and tannin exhibit enhanced mechanical properties, decreased curing temperatures and shortened pressing durations, and are devoid of isocyanates. The characterization of NIPU adhesives based on lignin and tannin was conducted using various analytical techniques, including Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), matrix-assisted laser desorption/ionization with time-of-flight (MALDI-TOF) mass spectrometry, and gel permeation chromatography (GPC). The adhesive performance of tannin-based NIPU resins was shown to be superior to that of lignin-based NIPUs. This paper elucidates the potential of lignin and tannin as alternate sources for polyols in the manufacturing of NIPUs, specifically for their application as wood adhesives.