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Metal-organic frameworks (MOFs) are promising catalysts for producing clean energy and environmental-based applications. This paper reported one-pot encapsulation of guest molecules, e.g., thiourea (TU) and D-Glucose-6-phosphate disodium salt dihydrate (G6P-Na2), into zeolitic imidazolate frameworks (ZIF-67), denoted as S@ZIF-67 and P@ZIF-67, respectively. The organic guest molecules offered the synthesis of cobalt-based materials (e.g., Co3O4, CoP, and CoS), embedded heteroatoms (P, N, and S) via carbonization. The materials were tested for hydrogen generation via sodium borohydride (NaBH4) hydrolysis. ZIF-67, S@ZIF-67, and P@ZIF-67 displayed maximum hydrogen generation rates (HGRmax) of 27,273, 24,000, and 60,000 mLH2 gcat−1 min−1, respectively, using 20 mg of the catalyst and 0.2 wt.% of NaBH4 at 60 °C. The materials were also investigated as potential catalysts for the adsorption and catalytic degradation of water pollutants such as organic dyes, e.g., methyl orange (MO) and Congo red (CR), with degradation efficiency of 100% and 99% in a short time (30–60 min).
Heterogeneous photocatalysis is a promising technology to overcome the problems associated with the energy crisis and environmental pollution. Therefore, the design of a reusable dual function photocatalyst has been studied extensively. Herein, MIL-53 (Fe) was used to fabricate Fe3O4@C on which TiO2 was deposited via a sol-gel route to form Fe3O4@C@TiO2 (FCT) double core-shell nanocomposite. Thermal treatment effect on photocatalytic activity under different atmospheres (air, argon and hydrogen) has been investigated. Then, the temperature was optimized (300-400 °C) under hydrogen atmosphere. Furthermore, the photocatalytic performance of the prepared composite on Rose Bengal (RB) dye degradation and hydrogen generation via water-splitting has been evaluated. The FCT sample treated at 350 °C in H2-atmosphere (FCT/H350) showed significant improvement in photodecomposition of 100 ppm of RB which completely disappeared within 40 min of the reaction. The apparent rate constant of FCT/H350 was 8.71 × 10−2 min−1, which is 4-folds faster than that of bare-TiO2. Moreover, the FCT/H350 exhibited an initial hydrogen generation rate (HGR) of 1593 µmol·g−1·h−1. Spectroscopic and electrochemical measurements were conducted to investigate the possible photocatalytic mechanism and photogenerated charge carriers pathway. This study aims to develop a magnetically separable, high-performance, and bifunctional catalyst for photocatalytic applications.
This work describes the synthesis of Fe-doped mesoporous anatase and brookite polymorphs of TiO2 in the occurrence of P-123 surfactant at varying Fe3+ ions contents (0.5–2%). The photocatalytic performance of the newly synthesized Fe–TiO2 was evaluated for phenol degradation compared to the parent TiO2, commercial P25 and 2%Fe–P25 under the solar simulator. XRD and TEM results illustrated that the construction of TiO2 NPs with brookite and anatase phases and the diameter of 10 nm was achieved. The surface area of 2%Fe–TiO2 NPs (100 m2/g) revealed a large two times compared to that of P25 (50 m2/g). Interestingly, the optimum 2%Fe–TiO2 photocatalyst exhibited complete degradation phenol within 40 min, and it was two times greater than that bare TiO2 and commercial P25 under simulated solar light. The rate constant for degradation of phenol over 2% Fe–TiO2 was enhanced 5.5 and 2.93 folds than that P25 and bare TiO2 NPs. The photocatalytic enhancement performance of Fe–TiO2 photocatalyst was supposedly created from the got better utilization of the visible light range. This is because Fe3+ ions can serve as a transient capturing site for photoinduced hole-electron, which suppressed the charge carriers' recombination and extended their lifetime. Photoelectrochemical measurements such as electrochemical impedance spectroscopy, chronoamperometry and cyclic voltammetry were conducted to verify and confirm the photocatalytic performance of the newly synthesized photocatalysts
The resources of clean water worldwide are very limited, and climate change is already affecting the available supplies. Therefore, developing a low-cost, highly efficient, and recyclable adsorbent to upgrade water quality has become an essential task. Herein, we report the fabrication of activated carbon (AC) adsorbents derived from lignocellulosic wastes. Both physical and chemical activation were investigated to modify the surface texture properties. The results indicated that increasing the activation temperature, whether physically or chemically, increases the specific surface area (SBET). On the contrary, increasing the amount of the chemical activating agent significantly decreases the SBET values. The SBET of 1771, 2120, and 2490 m2 g−1 were obtained for water vapor, K2CO3 and KOH, at activation temperatures of 950 °C, 800 °C, and 800 °C, respectively. Methylene blue (MB) and phenol were used as adsorbates for the adsorption experiment. Adsorption of methylene blue dye revealed the ability of the water activated carbon to remove more than 95% of the dye (100 ppm) within 5 min with an adsorption capacity of 148.8 mg g−1. For phenol adsorption, Several parameters were investigated, including initial concentration (50–250 ppm), pH (2–10), contact time (5–60 min), and temperature (25–45 °C). The highest adsorption capacity of phenol achieved was 158.9 mg g−1. The kinetics of adsorption of phenol was better described by pseudo-second-order reaction while the isotherm process using Langmuir model. This study presents a roadmap for conversion of lignocellulosic biomass waste into highly efficient porous carbon adsorbents.
Ulcerative colitis (UC) is one of the most common subtypes of inflammatory bowel disease (IBD) that affects the colon and is characterized by severe intestinal inflammation. Canagliflozin is a widely used antihyperglycemic agent, a sodium-glucose cotransporter-2 (SGLT2) inhibitor that enhances urinary glucose excretion. This study aims to provide insights into the potential benefits of canagliflozin as a treatment for UC by addressing possible cellular signals. Acetic acid (AA; 4% v/v) was administered intrarectally to induce colitis. Canagliflozin is given orally at a dose of 10 mg/kg/day. Canagliflozin attenuates inflammation in AA-induced colitis, evidenced by significant and dose-dependently downregulation of p38 MAPK, NF-κB-p65, IKK, IRF3, and NADPH-oxidase as well as colonic levels of IL-6 and IL-1β and MPO enzymatic activity. Canagliflozin mitigates colonic oxidative stress by decreasing MDA content and restoring SOD enzymatic activities and GSH levels mediated by co-activating of Nrf2, PPARγ, and SIRT1 pathways. Moreover, an in-silicostudy confirmed that canagliflozin was specific to all target proteins in this study. Canagliflozin's binding affinity with its target proteins indicates and confirms its effectiveness in regulating these pathways. Also, network pharmacology analysis supported that canagliflozin potently attenuates UC via a multi-target and multi-pathway approach.
In this study, we successfully used the Suzuki-Miyaura reaction to prepare three novel conjugated microporous polymers (CMPs) that include tetraphenylethene (TPE): TPE-Ph-Th, TPE-Ph-Tha, and TPE-Ph-BSu. Using methods like FTIR and solid-state NMR, we examined the chemical composition and functional groups in the TPE-Ph CMPs. The TPE-Ph-BSu CMP's thermal characteristics were also examined, and they showed remarkable features with a decomposition temperature (Td10) of 535 °C and a char yield of 73 wt%. We also looked at TPE-Ph-Th CMP, which had a pore size of 2.0 nm and a surface area (SBET) of 67 m2 g−1. We carried out photoluminescence (PL) and electrochemical investigations to evaluate the potential of TPE-Ph CMPs for supercapacitor applications and their capability to detect p-nitrophenol (PNP). According to our electrochemical investigation, the TPE-Ph-Tha and TPE-Ph-BSu CMPs both exhibited exceptional capacitance, reaching 51 and 52 F g−1 at a current density of 0.5 A g−1, respectively. Furthermore, even after 5000 cycles, these CMPs still retained 80% of their capacitance, demonstrating their remarkable capacitance retention. In conclusion, synthetic TPE-Ph CMPs have several benefits, including outstanding electrochemical performance and thermal stability. Additionally, they successfully detect PNP using fluorescence-based sensing without interference, making them adaptable materials suited for a variety of applications, including the detection of pollutants (as PNP has shown) and the usage of supercapacitors.
The development of biodegradable and active cellulosic-based heterogeneous catalysts for the synthesis of different organic compounds would be attractive in pharmaceutical and petrochemical-related industries. Herein, a post-sulfonated composite of one-pot synthesized magnetite (Fe3O4) and cellulose nanocrystals (CNCs) was used as an effective and easily separable heterogeneous catalyst for activating the Knoevenagel and Thorpe–Ziegler reactions. The composite was developed hydrothermally from microcrystalline cellulose (MCC), iron chlorides, urea, and hydrochloric acid at 180 °C for 20 h in a one-pot reaction. After collecting the magnetic CNCs (MCNCs), post-sulfonation was performed using chlorosulfonic acid (ClSO3H) in DMF at room temperature producing sulfonated MCNCs (SMCNCs). The results confirmed the presence of sulfonated Fe3O4 and CNCs with a hydrodynamic size of 391 nm (±25). The presence of cellulose was beneficial for preventing Fe3O4 oxidation or the formation of agglomerations without requiring the presence of capping agents, organic solvents, or an inert environment. The SMCNC catalyst was applied to activate the Knoevenagel condensation and the Thorpe–Ziegler reaction with determining the optimal reaction conditions. The presence of the SMCNC catalyst facilitated these transformations under green procedures, which enabled us to synthesize a new series of olefins and thienopyridines, and the yields of some isolated olefins and thienopyridines were up to 99% and 95%, respectively. Besides, the catalyst was stable for five cycles without a significant decrease in its reactivity, and the mechanistic routes of both reactions on the SMCNCs were postulated.