Journals
2025 EN
Das Gobinda · Singha Roy Suprobhat · Abou Ibrahim Fayrouz
+15 more
Abstract Developing a low‐cost, robust, and high‐performance electrocatalyst capable of efficiently performing both the oxygen evolution reaction (OER) and the hydrogen evolution reaction (HER) under both basic and acidic conditions is a major challenge. This area of research has attracted much attention in recent decades due to its importance in energy storage and conversion. Herein, we report the synthesis of two imine‐linked isoindigo‐based covalent organic networks I‐TTA and I‐TG (I=Isoindigo, TTA=4,4′,4′′‐(1,3,5‐triazine‐2,4,6‐triyl)‐trianiline, TG=triamino‐guanidinium hydrochloride salt). By introducing two amine core units with different planarity, such as triazine and ionic guanidinium units, we control the morphology, crystallinity, and corresponding electrocatalytic properties of the materials. The combination of isoindigo dialdehyde with a planar triazine core, leads to the formation of thin, highly crystalline, planar two dimensional (2D) nanosheets covalent organic framework (COF), I‐TTA whereas its combination with ionic non‐planar guanidinium core leads to an amorphous covalent organic polymer (COP), I‐TG with a fibrous morphology. The sheet‐like crystalline I‐TTA COF shows better electrocatalytic activity compared to the amorphous fibrous I‐TG COP. I‐TTA exhibits a current density of 10 mA cm −2 at an overpotential of ~134 mV for HER (in 0.5 M H 2 SO 4 ) and ~283 mV for OER (in 1 M KOH). The electrocatalytic activity of the I‐TTA COF in the OER exceeds that of other metal‐free COFs. The catalytic activity is maintained even after 24 hours of chronoamperometry and 500 cycles of cyclic voltammetry (CV) at high scan rates.
Journals
2025 EN
Chen Hengyue · Ruan Pengchao · Zhang Hao
+4 more
Abstract Despite the widespread interest in electrolytic Zn‐MnO 2 batteries with excellent output voltage and high theoretical capacity, the spontaneous disproportionation reaction of free Mn 3+ along with the disorderly deposited inactive MnO 2 results in the low Mn 2+ /MnO 2 conversion reversibility, which seriously affects their cycling stability. Here, we propose a novel aqueous SiO 2 colloidal electrolyte with FeSO 4 mediator (denoted as SF electrolyte) based on a bidirectional electrochemical‐chemical model to achieve dual regulation of the MnO 2 deposition/dissolution process. During the charging process, the SiO 2 colloidal particles located at the carbon felt interface and the electrolyte bulk phase simultaneously provide sufficient disproportionation sites for the diffused Mn 3+ to guide the orderly rapid deposition of MnO 2 . Meanwhile, the introduction of Fe 2+ mediators during the discharge process can sufficiently react with MnO 2 on the SiO 2 particles in the electrolyte, thereby further enabling the efficient conversion of Mn 2+ /MnO 2 . Consequently, electrolytic Zn‐MnO 2 battery with SF electrolyte can stably run for 550 cycles at 10 mAh cm −2 and achieve superior reversibility at a high area capacity of 20 mAh cm −2 . This work demonstrates the feasibility of colloidal electrolytes in modulating electrochemical‐chemical processes to stabilize electrolytic Zn‐MnO 2 batteries.
Journals
2025 EN
Wu Jiajun · Chugh Vishal · SharpBucknall Lachlan
+3 more
A single propargylic alcohol beam enters a catalyst prism and splits into three product beams via adaptive rhodium catalysis assisted by a Lewis‐acidic secondary sphere. In their Communication ( e202515903 ), Christophe Werlé and co‐workers describe a rhodium catalyst featuring a triazine ligand with a borane arm that selectively transforms a propargylic alcohol into retained alkynes, allylic ethers, or (E)‐alkenes.
Journals
2025 EN
Wu Jiajun · Chugh Vishal · SharpBucknall Lachlan
+3 more
Abstract Achieving chemoselective transformations of multifunctional molecules under mild and sustainable conditions remains a central challenge in catalysis. Here, we show that a rhodium complex equipped with a Lewis acidic secondary coordination sphere can mediate condition‐dependent, divergent hydrogenation of propargylic alcohols. By tuning the reaction medium, the system selectively yields one of three products—retained alkynes, allylic ethers, or ( E )‐alkenes—from a single substrate–catalyst pair under hydrogen. Mechanistic studies implicate π‐allyl and rhodium hydride intermediates, with solvent polarity and nucleophilicity steering the reaction pathway. Control experiments confirm the critical roles of both molecular hydrogen and the boron Lewis acid in enabling divergent selectivity. These findings demonstrate how rational secondary‐sphere design can enable adaptive catalysis and provide a platform for programmable bond transformations in multifunctional substrates.
Journals
2025 EN
Rathmann Florian · Abdelsalam IbrahiM · Wang Shiqi
+8 more
Abstract Plasmonic‐catalytic nanostructures enable coupling light harvesting with chemical transformations, yet their performance critically depends on nanoscale architecture and metal‐support interactions. Here, we synthesize Au@Ru core–shell nanoparticles with tunable Ru coverage and immobilize them on TiO 2 to create hybrid catalysts for CO 2 methanation. By controlling Ru shell thickness, we identifyAu 60 Ru 40 /TiO 2 , featuring a thin, discontinuous shell (∼2 nm Ru nanocrystallites), as the most active composition. This catalyst combines abundant Ru active sites with preservation of the Au core's localized surface plasmon resonance (LSPR). Under 545 nm illumination, it shows a 335% rate enhancement over dark conditions at 190 °C, outperforming commercial Ru/C and remaining stable for 85 h. Optical, structural, and kinetic analysis indicate that illumination accelerates the methanation without changing the rate‐determining step, consistent with a dominant photothermal contribution. Density functional theory reveals that TiO 2 induces strong metal‐support interactions, upshifts the Ru d‐band center, strengthens CO 2 adsorption, and lowers the barrier for the first hydrogenation step, shifting the rate‐limiting step to CH 4 desorption. These results establish Au@Ru/TiO 2 as an efficient platform for visible‐light‐assisted thermocatalysis and demonstrates that nanoscale shell engineering as a generalizable strategy to optimize plasmonic catalysts for CO 2 hydrogenation and beyond.
Journals
2025 EN
Luo Zijie · Xu Yijia · Fan Jiayi
+4 more
Abstract Type‐2 diabetes (T2D) is a growing global health crisis, with over 90% of diabetes cases attributed to this condition. Misfolding and aggregation of islet amyloid polypeptide (IAPP) is a hallmark of early T2D, contributing to pancreatic β‐cell dysfunction. While significant progress has been made in developing sensors for amyloids implicated in neurodegeneration, fluorescent probes for detecting IAPP aggregates remain limited. We report a series of flavonoid derivatives designed for enhanced IAPP fibril detection. The probes feature modifications, including methoxy substitution at C7 and varying amines at C4, which enhance their binding affinity for IAPP fibrils compared to the widely used Thioflavin T (ThT). The leading probes, F4 and MF1 , exhibited over 10‐fold increased binding affinity compared to ThT, alongside ratiometric fluorescence due to excited‐state intramolecular proton transfer. F4 and MF1 were applied to image IAPP aggregates in pancreatic β‐cells and zebrafish tissue sections, where both probes demonstrated specific imaging of IAPP fibrils. These probes also demonstrated reduced fluorescence when IAPP monomers were incubated with inhibitors, indicating fibril disassembly. Our results position F4 and MF1 as promising tools for exploring the pathological role of IAPP aggregation in diabetes and for high‐throughput screening of IAPP aggregation inhibitors.
Journals
2025 EN
Reisenhofer Antonia · Belaj Ferdinand · Ibrahim Malek Y. S.
+1 more
ABSTRACT Hydrosilylation of ketones using manganese complexes has emerged as an efficient and safer alternative to traditional reduction methods. Reported manganese(I) systems are typically monomeric Mn(I) carbonyl bromide catalysts, while dimeric systems have remained largely unexplored. Here, three manganese complexes of the dimeric type [{Mn(6‐R‐PyS)(CO) 3 } 2 ] (R = H 1 , CH 3 2 , CF 3 3 ) featuring thiopyridine ligands and Mn 2 S 2 cores are found to be catalysts in the visible light‐induced hydrosilylation of ketones at room temperature. Notably, optimal reactivity was achieved when the irradiation wavelength was set at 427 nm. Furthermore, a catalyst loading of 0.1 mol% was sufficient to achieve full conversion within 90 min over a wide scope of acetophenones and aliphatic ketones. However, the reactivity was drastically reduced when the sterically demanding, electron withdrawing CF 3 group was introduced to the ligand. An induction time of 10 min was observed that can be attributed to the formation of the active species, after which the reaction was found to proceed without irradiation. Further investigations into the mechanism revealed that upon irradiation of solutions of the complexes, CO is released forming an undefined paramagnetic species. In conclusion, for fast catalysis with the dinuclear Mn(I) complexes sterically unhindered ligands and activation with light are required. Furthermore, the catalytic reaction is amenable to continuous flow chemistry as exemplified by the hydrosilylation of acetophenone with 0.1 mol% of catalyst 1 . When carried out in a photoflow reactor, the reaction is completed after 14.2‐min resistant time.
Journals
2025 EN
Waziri Ibrahim · Sookai Sheldon · Yusuf Tunde L.
+2 more
ABSTRACT Metal complexes derived from salicylaldehyde‐based Schiff bases are among the frontrunners in the pursuit of precise and potent cancer treatments due to their remarkable prowess. In this study, salicylaldehyde‐based Schiff base ( HL ) was prepared via a reaction between 2‐amino‐5‐benzonitrile and salicylaldehyde. Subsequently, HL was further reacted with Ni (II), Co (II), Cu (II) and Pd (II) ions using their respective metal salts to obtain homoleptic mononuclear complexes ( C1 – C4 ). The composition of HL and C1 – C4 were determined using 1 H and 13 C NMR, UV–Vis, FTIR, CHN, SEM–EDX and HRMS analyses. In addition, the structural geometries of HL , C1 , C3 and C4 were determined in solid state using single crystal X‐ray diffraction analysis and corroborate with the mentioned characterization techniques employed. The stability of compounds was assessed through time‐dependent UV–vis spectroscopy, revealing that C2 exhibited the highest stability under the experimental conditions. Subsequently, the anticancer effects of HL and C2 were tested on breast cancer cell lines (MCF‐7) using MTT, LDH and ATP assays. Both HL and C2 displayed potential cytotoxicity on the MCF‐7 cell line, in which C2 displayed a better inhibition effect than a standard chemotherapeutic agent, doxorubicin (DOX), with IC 50 of 43.08 μM. We postulate that the mechanism by which C2 may function is by binding to DNA (K a $$ {K}_a $$ = 0.114 (± 0.02) × 10 4 ) and intercalation (shown by UV‐CD and UV‐LD spectroscopy) at the AT rich sites. These data were corroborated in silico by extra precision (XP) docking and molecular dynamic (MD) simulations.
Journals
2025 EN
Pato Abdul Hameed · Chandio Imran Ali · Javaid Saba
+8 more
ABSTRACT The proposed study was undertaken to design a facile, straightforward recoverable Titania@ITO‐grown nanocatalyst, owning ironic catalytic sites synthesized via a liquid phase deposition protocol. The size, shape, charge, and morphological characteristics of the synthesized functional nanocatalyst were determined via zeta seizer, XRD, zeta potential, and SEM, critically disclosing ⁓5–6 nm, anatase crystalline nature, −44.0 mV, and flakes or sheet‐like morphology, respectively. The reuse of the nanocatalyst particles was evaluated for their catalytic and antimicrobial efficiency. The obtained data revealed that the titania nanocatalyst is promising for ultrafast reduction of organic pollutants (4‐nitrophenol) with 99% reduction efficiency, utilizing only 120 μg within 60 s following microwave‐assisted protocols. Moreover, phenomenal antibacterial activity was disclosed by the titania nanocatalyst against both gram‐positive and gram‐negative bacteria. The anticipated nanocatalyst is advantageous due to its ultrafine and economical design, a significant amount of reduction capabilities in a short space of time, along with extreme recyclability, with a negligible loss in reduction abilities. The nanocatalyst provided here is more valuable and useful than the disclosed methods, symbolizing an exceptional commercial icon.
Journals
2025 EN
AbdelMegid Mohamed · Adly Omima M. I. · Ibrahim Magdy A.
+1 more
ABSTRACT The study focused on the synthesis, structural analysis, and characterization of four metal complexes (Ni‐ MCT , Co‐ MCT , VO‐ MCT , and Cd‐ MCT ) derived from 6‐methyl‐4‐[(chromon‐3‐yl)methylidene]amino‐3‐thioxo‐3,4‐dihydro‐1,2,4‐triazin‐5(2 H )‐one ( MCT ) as a ligand. A range of techniques including elemental analysis, UV–Vis, FT‐IR, 1 H‐NMR, ESR, XRD, molar conductivity, magnetic susceptibility, and thermal analysis were used to confirm the octahedral structures. The ligand coordinated with the metal ion via O, N, and S donor atoms, forming mononuclear complexes. The anticancer potential was evaluated using HepG‐2 liver cancer cells, revealing that Cd‐ MCT and VO‐ MCT exhibited notable cytotoxic effects, with IC 50 values lower than those of other synthesized complexes and conventional chemotherapeutic drugs. Additionally, cytotoxicity was assessed in normal human cells, where VO‐ MCT demonstrated a comparatively higher IC 50 value, indicating lower toxicity to healthy cells than the other compounds. DFT calculations supported the molecular structures and provided quantum chemical insights of the current complexes. A QSAR model correlated DFT‐derived descriptors with biological activity (pIC 50 ). ADMET analysis indicated promising oral bioavailability. The molecular docking studies suggested an interaction with the CDK2 kinase, highlighting Cd‐ MCT and VO‐ MCT as promising candidates for further pharmacological exploration in drug development.