Publications

Aminated polyethersulfone (PES–NH2) has been synthesized and used with carboxylated activated carbon (AC–COOH) as an adsorbent using two different methods: in situ and ex situ techniques. The chemical modification of polyethersulfone (PES) to introduce –NH2 functions was used to overcome the hydrophobicity of PES which maximizes its use in water treatment applications whereas applying AC–COOH to this polymer provides a promising effective method as an adsorbent-separation technique to remove dye pollutants from wastewater. The structure and characterization of aminated polyethersulfone with carboxylated activated carbon (PES–NH2–AC–COOH) were identified using proton nuclear magnetic resonance (1H-NMR), Fourier transform infrared (FT-IR spectroscopy), X-ray diffraction (XRD), thermal analysis (TA), and a scanning electron microscopy (SEM). The performance of PES–NH2 in situ and ex situ with AC–COOH was tested for the adsorption of cationic (methylene blue) and anionic (acid red 1) dyes from an aquatic environment. The results of the study showed a better thermal stability for the PES–NH2 with 20% AC–COOH with both in situ and ex situ techniques as well as an excellent adsorption performance in comparison with the bare PES–NH2. The resultant polymers displayed significantly high adsorption rates for the acid red dye (60% and 68%) and methylene blue dye (61% and 88%) by PES–NH2 with AC–COOH using in situ and ex situ techniques, respectively, in comparison with the control (PES–NH2) which showed lower adsorption rates for both dyes (21% for acid red and 33% for methylene blue). Lastly, the study experimental measurements found the most suitable model to describe the kinetic behavior of the acid red dye adsorption by our developed polymer (by PES–NH2 with AC–COOH) to be the pseudo-second-order kinetic model.

Drug waste and inefficiencies in pharmaceutical supply chains contribute to significant economic losses and environmental harm. Pharmacists play a crucial role in minimizing drug waste through inventory optimization, proper medication management, and patient education. This paper explores strategies pharmacists can employ to enhance supply chain efficiency, reduce unnecessary drug disposal, and promote sustainable practices. Key interventions include just-in-time inventory systems, medication therapy management, and collaboration with healthcare providers. The findings highlight the pharmacist’s impact on cost savings, environmental sustainability, and improved patient outcomes.

The sol-gel technique was adopted to synthesize the zinc oxide (ZnO) nanoparticles. Nano-sized ZnO particles are embedded in-situ to the poly(vinyl alcohol) (PVA) matrix to form the nanocomposite polymeric membranes. The nanocomposite membranes were fabricated by varying concentration of ZnO nanoparticles of 2.5, 5, and 10 wt.% in the base PVA membrane matrix. The membranes were crosslinked using tetraethyl orthosilicate (TEOS) followed by hydrolysis and co-condensation. Immersion in a 2 molar sulphuric acid (H2SO4) bath produced sulfonated membranes. The membranes were characterized using Fourier transform infrared (FTIR) and scanning electron microscopy (SEM). The fabricated nano-composite membranes are being evaluated for proton exchange membrane fuel cell research (PEMFC). The computed test results demonstrate that increasing the concentration of ZnO in the membrane increased the ionic exchange capacity and proton conductivity efficiency of the nano-composite membranes. The incorporation of a quantum quantity of ZnO particles in the membrane improved the presentation in terms of proton conductivity characteristics. Membranes demonstrated excellent proton conductivity (10−2 S cm−1 range) while consuming less hydrogen gas. The highest measured proton conductivity is observed for 10 wt.% ZnO embedded PVA membrane and the value is 15.321 × 10−2 S cm−1 for 100% RH. The combination of ZnO and PVA nanocomposite membrane is a novel, next-generation eco-friendly method that is economical and convenient for large-scale commercial production in fuel cell applications.

As a non‐toxic species, Zn fulfills a multitude of biological roles, but its promoting effect on electrocatalysis has been rarely explored. Herein, the theoretic predications and experimental investigations that nonelectroactive Zn behaves as an effective promoter for CoP‐catalyzed hydrogen evolution reaction (HER) in both acidic and alkaline media is reported. Density function theory calculations reveal that Zn doing leads to more thermal‐neutral hydrogen adsorption free energy and thus enhanced HER activity for CoP catalyst. Electrochemical tests show that a Zn 0.08 Co 0.92 P nanowall array on titanium mesh (Zn 0.08 Co 0.92 P/TM) needs overpotentials of only 39 and 67 mV to drive a geometrical catalytic current of 10 mA cm ‐2 in 0.5 m H 2 SO 4 and 1.0 m KOH, respectively. This Zn 0.08 Co 0.92 P/TM is also superior in activity over CoP/TM for urea oxidation reaction (UOR), driving 115 mA cm ‐2 at 0.6 V in 1.0 m KOH with 0.5 m urea. The high HER and UOR activity of this bifunctional electrode enables a Zn 0.08 Co 0.92 P/TM‐based two‐electrode electrolyzer for energy‐saving hydrogen production, offering 10 mA cm ‐2 at a low voltage of 1.38 V with strong long‐term electrochemical stability.

We report here a comparative theoretical and experimental study of four triazine-based hydrazone derivatives. The hydrazones are synthesized by a three step process from commercially available benzil and thiosemicarbazide. The structures of all compounds were determined by using the UV-Vis., FT-IR, NMR (1H and 13C) spectroscopic techniques and finally confirmed unequivocally by single crystal X-ray diffraction analysis. Experimental geometric parameters and spectroscopic properties of the triazine based hydrazones are compared with those obtained from density functional theory (DFT) studies. The model developed here comprises of geometry optimization at B3LYP/6-31G (d, p) level of DFT. Optimized geometric parameters of all four compounds showed excellent correlations with the results obtained from X-ray diffraction studies. The vibrational spectra show nice correlations with the experimental IR spectra. Moreover, the simulated absorption spectra also agree well with experimental results (within 10-20 nm). The molecular electrostatic potential (MEP) mapped over the entire stabilized geometries of the compounds indicated their chemical reactivates. Furthermore, frontier molecular orbital (electronic properties) and first hyperpolarizability (nonlinear optical response) were also computed at the B3LYP/6-31G (d, p) level of theory.

Co(hydro)oxides show unsatisfactory catalytic activity for the hydrogen evolution reaction (HER) in alkaline media, and it is thus highly desirable but still remains a challenge to design and develop Co(hydro)oxide derived materials as superb hydrogen-evolving catalysts using a facile, rapid and less energy-intensive method. Here, we propose a cathodic electrochemical activation strategy toward greatly boosted HER activity of a Co₃O₄ nanoarray via room-temperature cathodic polarization in sodium hypophosphite solution. After activation, the overpotential significantly decreases from 260 to 73 mV to drive a geometrical catalytic current density of 10 mA cm^-2 in 1.0 M KOH. Notably, this activated electrode also shows strong long-term electrochemical durability with the retention of its catalytic activity at 100 mA cm^-2 for at least 40 h.

The selectivity toward lower olefins during the methanol-to-olefins conversion over H-SAPO-34 at reaction temperatures between 573 and 773 K has been studied with a combination of operando UV-vis diffuse reflectance spectroscopy and online gas chromatography. It was found that the selectivity toward propylene increases in the temperature range of 573-623 K, while it decreases in the temperature range of 623-773 K. The high degree of incorporation of olefins, mainly propylene, into the hydrocarbon pool affects the product selectivity at lower reaction temperatures. The nature and dynamics of the active and deactivating hydrocarbon species with increasing reaction temperature were revealed by a non-negative matrix factorization of the time-resolved operando UV-vis diffuse reflectance spectra. The active hydrocarbon pool species consist of mainly highly methylated benzene carbocations at temperatures between 573 and 598 K, of both highly methylated benzene carbocations and methylated naphthalene carbocations at 623 K, and of only methylated naphthalene carbocations at temperatures between 673 and 773 K. The operando spectroscopy results suggest that the nature of the active species also influences the olefin selectivity. In fact, monoenylic and highly methylated benzene carbocations are more selective to the formation of propylene, whereas the formation of the group of low methylated benzene carbocations and methylated naphthalene carbocations at higher reaction temperatures (i.e., 673 and 773 K) favors the formation of ethylene. At reaction temperatures between 573 and 623 K, catalyst deactivation is caused by the gradual filling of the micropores with methylated naphthalene carbocations, while between 623 and 773 K the formation of neutral poly aromatics and phenanthrene/anthracene carbocations are mainly responsible for catalyst deactivation, their respective contribution increasing with increasing reaction temperature. Methanol pulse experiments at different temperatures demonstrate the dynamics between methylated benzene and methylated naphthalene carbocations. It was found that methylated naphthalene carbocations species are deactivating and block the micropores at low reaction temperatures, while acting as the active species at higher reaction temperatures, although they give rise to the formation of extended hydrocarbon deposits.

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

In this paper, we develop an environmentally friendly, one-pot strategy toward rapid preparation of Ag nanoparticle-decorated reducd graphene oxide (AgNPs/rGO) composites by heating the mixture of GO and AgNO(3) aqueous solution in the presence of sodium hydroxide at 80 °C under stirring. The reaction was accomplished within a short period of 10 min without extra reducing agent. As-synthesized AgNPs/rGO composites have been successfully applied in photocurrent generation in the visible spectral region.