RESUMEN

The photocatalytic production of hydrogen (H2) from water is a vital avenue towards sustainable energy and addressing global environmental challenges. To maximize efficiency, harnessing the synergistic effects of multiple co-catalysts is essential, as these interactions can significantly enhance performance. In this study, we introduce a ternary heterojunction composed of a nickel-imidazole framework (Ni-MOF), graphitic carbon nitride (CN), and Ti3C2 MXene (TC), employing solvothermal and wet impregnation methods, featuring a well-designed Type II heterojunction and a noble metal-free Schottky junction for efficient hydrogen evolution. The Type II heterojunction between Ni-MOF and CN minimizes charge carrier recombination and promotes photogenerated electron generation, while TC as an electron acceptor enhances electron capture, increases participation in surface reactions, and augments active sites. Consequently, the Ni-MOF/CN/TC hybrid catalyst achieves outstanding photocatalytic hydrogen evolution under visible light, with a peak production rate of 1044.46 µmol/g over 3 hours, surpassing CN by 13 fold and Ni-MOF/CN by 50%. This work provides insights into MXene-based ternary systems, emphasizing the potential for enhanced light absorption and efficient charge separation, making it a promising platform for photocatalytic applications.

RESUMEN

Metal-Organic Frameworks (MOFs) are extensively used as electrode material in various sensing applications due to their efficacious porous nature and tunable properties. However, pristine MOFs lack conductive attributes that hinder their wide usage in electrochemical applications. Electropolymerization of several aromatic monomers has been a widely used strategy for preparing conducting electrode materials for various sensing applications in the past decades. Herein, we report a similar approach by employing the electropolymerization method to create a functional polymer layer to enhance the sensitivity of an Aluminium Organic Framework (DUT-4) for the selective detection of Chloramphenicol (CAP) antibiotic in aqueous environment. The combined strategy using the conducting polymer layer with the porous Al MOF provides surpassing electrochemical performance for sensing CAP with regard to the very low detection limit (LOD = 39 nM) and exceptionally high sensitivity (11943 µA mM-1 cm-2). In addition, the fabricated sensor exhibited good selectivity, reproducibility and stability. The developed method was successfully evaluated in various real samples including lake water and river water for CAP detection with good recovery percentages even at lower concentrations.

Asunto(s)

RESUMEN

Rising concerns of pesticide-induced neurotoxicity and neurodegenerative diseases like Parkinson's, Alzheimer's, and Multiple Sclerosis, are exacerbated by overexposure to contaminated waterbodies. Therefore, evaluating the risk accurately requires reliable monitoring of related biomarkers like dopamine (DA) through electrochemical detection. Layered double hydroxides (LDHs) have shown great potential in sensors. However, to meet the challenges of rapid detection of large patient cohorts in real-time biological media, they should be further tailored to display superior analytical readouts. Herein, a ternary LDH (Ni2CoMn0.5) was integrated with the sheets of thermally reduced graphene oxide (trGO), to expose more highly active edge planes of the LDH, as opposed to its generally observed inert basal planes. The improvement in detection performance through such a modulated structure-property is a prospect that hasn't been previously explored for any other LDH-based materials employed in sensing applications. The 2 folds superior electrochemical activity exhibited by the face-on oriented LDH with trGO as compared to the pristine LDH material was further employed for direct detection of DA in real blood plasma samples. Moreover, the designed sensor exhibited exceptional selectivity towards the detection of DA with a limit of detection of 34.6 nM for a wide dynamic range of 0.001-5 mM with exceptional stability retaining 88.56% of the initial current even after storage in ambient conditions for 30 days.

Asunto(s)