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We report the synthesis of an EDOT-functionalizedmcp ligand that enables direct immobilization of [M(mcp)X₂]complexes (M = Fe, Co, Cu, Ru) into conducting redox polymers(CRPs) via electropolymerization. Poly(EDOT-co-[Fe(EDOT-mcp)-X₂]) films were thoroughly characterized in both acetonitrile andwater using cyclic voltammetry, in situ conductance measurements,and in situ UV/Vis spectroelectrochemistry. These operando studiesdisentangle backbone doping from the Fe(III)/Fe(II) pendant groupredox transition, revealing that charge transport proceeds predominantly through the polymer backbone, while the pendant complexesoperate as discrete electroactive sites. The Fe redox potential is highlysensitive to electrolyte anion coordinating strength and concentration,reflecting ligand exchange at the labile sites. In water, theelectrochemical response is governed by proton-coupled electron transfer and is strongly affected by pH and buffer identity.Only when buffer ions penetrate the polymer bulk at sufficiently high buffer concentrations do the pendant groups experiencethe same effective proton activity as the surrounding electrolyte. Although attempts at catalytic water oxidation confirm Fe-centeredoxidation chemistry, the material undergoes rapid conductivity loss at anodic potentials, indicating backbone degradation underturnover conditions. These findings establish the EDOT-mcp platform as a versatile immobilization strategy for mcp-type metalcomplexes and highlight design requirements for improving stability in oxidative catalysis.

The valorization of biomass into renewable, high-performance, adsorbent materials offers a sustainable alternative to conventional synthetic sorbents. In this study, we investigate the potential of lignin derivatives as efficient adsorbents for removing the cationic dye Rhodamine B (RhB) from aqueous solutions. Five organosolv lignin derivatives were synthesized via a one-step process using phenol, catechol, resorcinol, pyrogallol, and hydroquinone as phenolic modifiers to introduce structural diversity. The influence of these modifications on the materials’ physicochemical properties and adsorption behavior was examined. Comprehensive characterization included ³¹P NMR, Brunauer–Emmet–Teller surface area analysis, size exclusion chromatography, thermogravimetric analysis, and dynamic light scattering. Among the derivatives, resorcinol-modified lignin (ReL) showed the highest RhB adsorption capacity (101.2 mg g⁻¹), attributed to its favorable textural properties—high surface area and pore volume—together with increased availability of functional groups, which collectively enhanced adsorption efficiency. Adsorption kinetics for all materials followed the pseudo-second-order model, indicating chemisorption as the dominant mechanism. Isotherm analyses revealed Langmuir-type monolayer adsorption for ReL, pyrogallol-modified, and hydroquinone-modified lignins. Moreover, ReL demonstrated good recyclability, retaining 62% of its adsorption efficiency after five adsorption–desorption cycles. Collectively, these results highlight the promise of structurally engineered lignin-based adsorbents as cost-effective, efficient, and reusable materials for sustainable wastewater treatment.

A series of zirconium-based MOFs with acclaimed stability was prepared and their ability to adsorb polyfluorinated pollutants was compared. A novel fluorinated UiO-67 analogue, UiO-67-F2, was synthesised alongside three previously reported materials: UiO-67-NH2, UiO-68-(CF3)2 and UiO-67. The structures were established and confirmed by powder X-Ray diffraction. UiO-67-NH2, UiO-68(CF3)2 and UiO-67-F2 were examined as sorbents for the perfluorinated gas, sulphur hexafluoride (SF₆) from the gaseous phase. The SF₆ uptake of UiO-67-NH2 and UiO-67-F2 at 100 kPa, 293 K, was high (5.54 and 5.24 mmol g ^-1 respectively). UiO-67-F2 exhibited a remarkable perfluorinated octanoic acid (PFOA) uptake of 928 mg_PFOA g ^-1_MOF in an aqueous solution, which far exceeded that of unmodified UiO-67 (872 mg_PFOA g ^-1_MOF at 1 000 mg_PFOA L ^-1_Water PFOA). This study has identified strengths and potential applications of the novel UiO-67-F2 and the impact of fluorine functionalization. The study also offers insight into the structure-property relations of UiO-based MOFs for their use as low-pressure SF6 storage materials and PFAS sorbents intended for water purification under ambient conditions.

With the growing interest in fabricating nanofiltration membranes using novel materials and techniques, there is an increasing need to evaluate the practical viability of innovative membranes at the early stages of development. In many materials research laboratories, access to professionally manufactured membrane-evaluation systems may be limited. Here we present a pressure-driven filtration system for evaluation of nanofiltration membranes, which can be constructed from 3D-printed parts and widely available off-the-shelf components at a cost of approximately 60 €. The system uses a stirred cross-flow design capable of circulating the feed solution in the filter cell and maintaining a stable solute concentration during extended filtration experiments—as in conventional cross-flow cells. It is suitable for the filtration of aqueous solutions containing dyes, inorganic salts, and dilute acids. Validation was performed by filtering a 2000 mg L−1 MgSO4 solution through a Veolia RL membrane at 7.6 bar, achieving a 96.5% rejection rate and a permeance of 7.5 L m−2 h−1 bar−1 after 24 h of continuous operation.

Molecular catalysts for water oxidation and other electrochemical transformations have been a focus of significant research over recent decades. Among these, α-[Fe(mcp)L2] complexes stand out as one of the most active non-heme iron-based molecular catalyst for water oxidation. This study investigates how the Fe(II)/Fe(III) redox potential of these catalysts varies with the identity of their labile ligands (L). Using cyclic voltammetry and complementary spectroscopic techniques (UV/Vis, 1H-NMR), we examined how ligands bind to the metal centre. Systematic variation of the labile ligand (L) demonstrated that the catalyst's redox potential in acetonitrile solution strongly depends on ligand identity. By introducing stoichiometric amounts of different anions to the electrolyte, the redox potential was tuned across a 1.5 V potential window.In aqueous solutions, the redox potential depended on both pH and electrolyte anion identity. These dependencies were successfully fitted to a thermodynamic model that was obtained by extending the typical proton-coupled electron transfer square scheme into a cube scheme that incorporates anion binding. The equation derived from this model provides valuable insights into the ligand-binding dynamics at the iron centre under diverse conditions.

This study explores the potential of phenolated lignin as a precursor for synthesizing graphene-like carbon materials through laser-induced carbonization (LIC). Key parameters─including formulation, laser speed, laser power, and lignin loading─were optimized to enhance the quality of the resulting LIC materials. Under optimized conditions, this method produced a high-quality, few-layer graphene-like carbon material. Comprehensive materials characterization (XPS, XRD, TGA, Raman spectroscopy, sheet resistivity, and elemental analysis) revealed that the material’s conductivity is driven by the formation of an sp2-hybridized conjugated carbon system and the reduction of both sp3-hybridized carbon and oxygen groups. The introduction of phenolic groups into the lignin structure enhanced its thermostability and conversion efficiency to graphene-like carbon, achieving a low sheet resistance of 6.7 Ω·sq–1. This study demonstrates that phenolated lignin is a promising precursor for the synthesis of conductive graphene-like carbon materials with excellent electronic properties, making it suitable for micro-supercapacitor applications. Furthermore, the resulting printed device exhibited a specific capacitance of 454 mF cm–3 (1.4 mF cm–2) at a scan rate of 5 mV s–1 in cyclic voltammetry (CV) mode and 286 mF cm–3 (0.86 mF cm–2) at a current density of 0.05 mA cm–2 in galvanostatic charge–discharge (GCD) mode.

Flexible supercapacitors hold promise for applications in wearable electronic devices. However, the challenges of achieving flexibility, miniaturization, and high volumetric capacitance persist. In this work, precise laser etching of cellulose composites, prepared via in-situ growth of conductive metal–organic frameworks (c-MOFs) on cellulose nanofibers (CNF), was employed to fabricate flexible, binder-free, and integrated microsupercapacitors (MSCs). The interfacial synthesis of Ni₃(HITP)₂ (a type of c-MOF) on the surface of CNF yields a continuous and uniform conductive shell, enabling efficient electron transfer along the CNF@c-MOF nanofibers. The interwoven structure of the nanofibers creates a hierarchical porous network with enhanced surface area featuring interconnected porous channels, enabling rapid ion transport. The laser etching technique facilitates one-step production of integrated MSCs with a precisely interdigitated configurations and micron-scale accuracy. The fabricated MSCs demonstrate excellent mechanical stability, with a tensile strength of up to 81.9 MPa, and remarkable flexibility, maintaining consistent electrochemical performance under bending stress. The flexible device, with a thickness of only 45 µm, achieves a high volumetric specific capacitance of 36.7 F cm⁻³ at a current density of 0.17 mA cm⁻² and a specific energy density of 2,497.5 µWh cm⁻³ at a power density of 53.3 mW cm⁻³. This study provides a new strategy for designing flexible, binder-free, integrated MSCs with high capacitances and long cyclic stability, demonstrating significant potential for applications in wearable electronics.