1. Hydrazone-linked covalent organic framework catalyst via efficient Pd recovery from wastewaterMahira Bashri, Sushil Kumar, Pallab Bhandari, Sasi Stephen, Matthew J. O'Connor, Safa Gaber, Tina Škorjanc, Matjaž Finšgar, Gisha Elizabeth Luckachan, Blaž Belec, 2024, izvirni znanstveni članek Opis: Global consumption and discharge of palladium (Pd) have raised environmental concerns but also present an opportunity for the sustainable recovery and reuse of this precious metal. Adsorption has proven to be an efficient method for the selective recovery of Pd from industrial wastewater. This study investigated a hydrazone-linked covalent organic framework (Tfpa-Od COF) as a potential material for the high-affinity adsorption of Pd2+ ions from wastewater, achieving a Kd value of 3.62 × 106 mL g–1. The electron-rich backbone of the COF contributes to its excellent selective removal efficiency (up to 100%) and adsorption capacity of 372.59 mg g–1. Furthermore, the Pd-adsorbed COF was evaluated as a sustainable catalyst for the Suzuki–Miyaura coupling reaction, demonstrating good catalytic conversion and recyclability. This work attempts to showcase a protocol for reusing waste palladium generated in water to fabricate heterogeneous catalysts and, thereby, promote the circular economy concept. Ključne besede: covalent organic frameworks, sustainability, catalysis, palladium adsorption, water purification Objavljeno v RUNG: 22.08.2024; Ogledov: 783; Prenosov: 6 Celotno besedilo (4,04 MB) Gradivo ima več datotek! Več... |
2. Crystallizing covalent organic frameworks from metal organic framework through chemical induced-phase engineeringAbdul Khayum Mohammed, Safa Gaber, Jesus Raya, Tina Škorjanc, Nada Elmerhi, Sasi Stephen, Pilar Pena-Sánchez, Felipe Gándara, Steven Hinder, Mark A. Baker, Kyriaki Polychronopoulou, Dinesh Shetty, 2023, izvirni znanstveni članek Opis: The ordered porous frameworks like MOFs and COFs are generally constructed using the monomers through distinctive metal-coordinated and covalent linkages. Meanwhile, the inter-structural transition between each class of these porous materials is an under-explored research area. However, such altered frameworks are expected to have exciting features compared to their pristine versions. Herein, we have demonstrated a chemical-induction phase-engineering strategy to transform a two dimensional conjugated Cu-based SA-MOF (Cu-Tp) into 2D-COFs (Cu-TpCOFs). The structural phase transition offered in-situ pore size engineering from 1.1 nm to 1.5–2.0 nm. Moreover, the Cu-TpCOFs showed uniform and low percentage-doped (~ 1–1.5%) metal distribution and improved crystallinity, porosity, and stability compared to the parent Cu-Tp MOF. The construction of a framework from another framework with new linkages opens interesting opportunities for phase-engineering. Ključne besede: metal organic framework, covalent organic framework, phase engineering, chemical transformation, porous materials Objavljeno v RUNG: 10.11.2023; Ogledov: 2886; Prenosov: 7 Celotno besedilo (3,64 MB) Gradivo ima več datotek! Več... |