Sustainable multifunctional hydrogels developed from waste-derived carbon materials and marine bioactive compounds represent a promising strategy for producing environmentally friendly antibacterial biomaterials. To the best of our knowledge, this is the first report on the fabrication of a poly(vinyl alcohol) (PVA)-based composite hydrogel by integrating hydrochar derived from pomegranate (Punica granatum) peel waste with an ethanolic extract of the brown macroalga Cystoseira corniculata, combining waste valorization with marine-derived bioactivity in a single multifunctional platform. The resulting hydrochar/PVA (H/PVA) and extract-loaded hydrochar/PVA (H/PVAC) hydrogels were characterized using Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), particle size, zeta potential, and conductivity measurements. Gas chromatography–mass spectrometry (GC–MS) analysis identified germacrene (49.1
For non-invasive glucose monitoring, a highly sensitive and reliable non-enzymatic glucose sensor based on a CuO–ZnO/polyaniline (CuO–ZnO/PANI) nanocomposite was fabricated. A simple chemical synthesis method was used to create the CuO–ZnO/PANI nanocomposite, which was coated onto a graphite electrode to enhance its electrochemical performance. X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), field-emission scanning electron microscopy (FESEM), and energy-dispersive X-ray spectroscopy (EDS) analyses and X-Ray Photoelectron Spectroscopy (XPS) confirmed the formation of the nanocomposite and the incorporation of CuO–ZnO within the conductive PANI matrix. Cyclic voltammetry (CV), differential pulse voltammetry (DPV), linear sweep voltammetry (LSV), square wave voltammetry (SWV), and chronoamperometry were used to assess the modified electrode’s electrochemical performance in 0.1 M phosphate-buffered saline (PBS, pH 7.4). With a low detection limit of 0.03 µM and a high sensitivity of 6.246 mA mM⁻¹ cm⁻², the CuO–ZnO/PANI-modified electrode demonstrated outstanding electrocatalytic activity toward glucose oxidation. The sensor also showed good repeatability and reproducibility, with relative standard deviation (RSD) values of 0.11
This study systematically evaluated Ti3C2Tx MXene adsorbents synthesized via conventional HF etching and a milder LiF/HCl in situ HF generation route for the removal of Reactive Blue 221 (RB221) from aqueous solutions. Adsorption performance was compared under varying operational conditions, including pH, temperature, adsorbent dosage, and initial dye concentration, together with kinetic, isotherm, thermodynamic, and structural analyses. Results showed that LiF/HCl-etched Ti3C2Tx consistently outperformed the HF-etched counterpart. At optimized conditions (pH 2, 60 degrees C), the LiF/HCl-derived MXene achieved nearly complete dye removal (similar to 95-100%) with rapid equilibrium within 10-20 min, while HF-etched samples showed lower efficiency (< 70%) and slower kinetics. The maximum adsorption capacity reached 145 mg g(-1) for LiF/HCl, compared to 100 mg g(-1) for HF-etched material. Kinetic modeling indicated that adsorption follows a pseudo-second-order model (R & sup2; > 0.99), suggesting chemisorption. Isotherm analysis fit the Langmuir model well for LiF/HCl samples (R & sup2; = 0.9994), indicating monolayer adsorption on a homogeneous surface. Thermodynamic parameters confirmed the process is spontaneous and endothermic, with improved adsorption at higher temperatures. Characterization (XRD, SEM, XPS, TGA) revealed increased interlayer spacing, better exfoliation, and higher surface functional groups (-OH/-O) in LiF/HCl-etched MXene. These features enhance electrostatic attraction, hydrogen bonding, and pi-pi interactions with RB221 molecules. Overall, the superior performance of LiF/HCl-etched Ti3C2Tx is attributed to its improved surface chemistry and morphology, highlighting the importance of etching strategy in tailoring MXene materials for efficient wastewater treatment applications.
Herein, a cost-effective biocomposite with a novel structure was fabricated and appraised for its adsorptive performance toward phenol from aqueous solutions. The synthetic route comprised the amalgamation of activated carbon derived from watercress seed waste with rhyolite, which was subsequently functionalized using sodium alginate. Comprehensive analytical evaluations via FTIR, XRD, BET, TGA/DTG, FESEM, EDX, and elemental mapping collectively substantiated the exceptional sorptive characteristics inherent to the prepared biosorbent. Through a statistical optimization framework based on the Box–Behnken design (BBD), corroborated by empirical trials, maximal phenol adsorption was achieved under the stipulated parameters: pH maintained at 6.5, adsorbent dosage set at 15 mg, and equilibration time fixed at 60 min, for a starting solute concentration held at 50 mg·L⁻¹. Kinetic profiles were adequately captured by the pseudo-first-order (PFO) model, whereas the Langmuir isotherm provided a markedly representation of the equilibrium data, with experimental adsorption capacities of 207.10, 211.72, and 216.92 mg·g⁻¹ at 25, 40, and 55 °C, respectively. Sophisticated computational simulations revealed that the underlying adsorptive mechanism involves a temperature-dependent, multimolecular, and multisite binding phenomenon. Thermodynamic assessments suggested the spontaneous and endothermic character of the adsorption performance, consistent with a physical adsorption pathway. This pathway is predominantly dictated by hydrogen-bonding forces and π–π stacking contacts, with associated binding energies falling within the interval of 24.26 to 27.34 kJ/mol. Based on a preliminary techno-economic assessment, the estimated production cost was 10.71 USD·kg⁻¹ of biosorbent, with a projected treatment cost of approximately 1.16 USD·m⁻³ for processing phenol-laden water (50 mg·L⁻¹) under the optimized conditions. The biocomposite demonstrated outstanding recyclability, preserving 90.28
Poly(aniline-co-p-phenylenediamine) (PANI-co-PPDA) electrospun nanofibers and those doped with chromium oxide nanoparticles (PANI-co-PPDA-Cr) were successfully synthesized and evaluated as electrode materials for supercapacitor applications. The morphology, electrical conductivity, and ion transport of the nanofibers were improved by the addition of chromium oxide Cr2O3 nanoparticles The morphology and structure of PANI-co-PPDA-Cr nanofibers were characterized using XRD, TGA, SEM, EDS, and TEM/HR-TEM. At a scan rate of 50 mV s−1, the optimized PANI-co-PPDA-Cr nanofiber showed an impressive areal capacitance of 1112 F g−1 at scan rate 2 mV.s−1 and maintained 84
