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The encapsulation of functional colloidal nanoparticles (100 nm) into single‐crystalline ZSM‐5 zeolites, aiming to create uniform core–shell structures, is a highly sought‐after yet formidable objective due to significant lattice mismatch and distinct crystallization properties. In this study, we demonstrate the fabrication of a core–shell structured single‐crystal zeolite encompassing an Fe3O4 colloidal core via a novel confinement stepwise crystallization methodology. By engineering a confined nanocavity, anchoring nucleation sites, and executing stepwise crystallization, we have successfully encapsulated colloidal nanoparticles (CN) within single‐crystal zeolites. These grafted sites, alongside the controlled crystallization process, compel the zeolite seed to nucleate and expand along the Fe3O4 colloidal nanoparticle surface, within a meticulously defined volume (1.5×107≤V≤1.3×108 nm3). Our strategy exhibits versatility and adaptability to an array of zeolites, including but not restricted to ZSM‐5, NaA, ZSM‐11, and TS‐1 with polycrystalline zeolite shell. We highlight the uniformly structured magnetic‐nucleus single‐crystalline zeolite, which displays pronounced superparamagnetism (14 emu/g) and robust acidity (~0.83 mmol/g). This innovative material has been effectively utilized in a magnetically stabilized bed (MSB) reactor for the dehydration of ethanol, delivering an exceptional conversion rate (98 %), supreme ethylene selectivity (98 %), and superior catalytic endurance (in excess of 100 hours). [ABSTRACT FROM AUTHOR]

A novel composite for the electrochemical sensing of tramadol (Tr) was developed by the inclusion of a metallocene mediator between two layers of conducting poly(3,4-ethylenedioxythiophene) (PEDOT) polymer, in the presence of sodium dodecyl sulfate (SDS), i.e., P/mediator/P...SDS. Three charge transfer mediators were evaluated: ferrocene carboxylic acid (FC1), ferrocene (FC2), and cobaltocene (CC) for Tr electrocatalytic oxidation. The FC1 charge mediator showed a relatively higher current response that was assisted by the electronic conduction of the polymer film. Moreover, SDS presented a great impact, resulting in the enhancement of the preconcentration and (or) accumulation of Tr ions at the interface, leading to faster electron transfer. In addition, the practical application of the proposed FC1 composite for the determination of Tr in real urine and serum samples was successfully achieved with adequate recovery results. Very low detection limits of 18.6 nM and 16 nM in the linear dynamic ranges of 7-300 [micro]Mnd 5-280 [micro]M, respectively, were obtained at the proposed sensor. Furthermore, the simultaneous determination of Tr with common interfering species, paracetamol (APAP), morphine (MO), dopamine (DA), ascorbic acid (AA) and uric acid (UA), proved excellent, with good resolution and large potential peaks separation. The excellent characteristics of the proposed composite such as high reproducibility, good sensitivity, selectivity, anti-interference ability, and good stability enhanced its application for determination of other narcotic drugs. Key words: tramadol, ferrocene carboxylic acid, conducting polymer, surfactant, morphine, paracetamol. Nous avons mis au point un nouveau composite pour la detection electrochimique du tramadol (Tr) par inclusion d'un mediateur a base de metallocene entre deux couches d'un polymere conducteur, le poly(3,4-ethylenedioxythiophene) (PEDOT), en presence de dodecylsulfate de sodium (SDS): (P/mediateur/P...SDS). Nous avons evalue trois mediateurs de transfert de charge, l'acide ferrocenecarboxylique (FC1), le ferrocene (FC2) et le cobaltocene (CC), pour l'oxydation electroca-talytique du Tr. Le mediateur de transfert de charge FC1 a presente, par rapport aux deux autres, une reponse de courant plus elevee, favorisee par la conduction electronique des couches de polymere. Par ailleurs, le SDS a eu un effet important, qui s'est traduit par une augmentation de la preconcentration et de l'accumulation d'ions Tr a l'interface et, consequem-ment, par un transfert d'electrons plus rapide. En outre, nous avons applique dans la pratique le composite FC1 propose a la determination du Tr dans des echantillons reels d'urine et de serum, et nous avons obtenu des resultats de recuperation adequats. Le capteur propose s'est caracterise par des limites de detection tres faibles, soit de 18,6 nm et 16 nm dans les intervalles dynamiques lineaires de 7 [micro]Ma300[micro]Metde5[micro]Ma280[micro]M, respectivement. De plus, la determination simulta-nee du Tr et d'especes interferentes courantes, a savoir le paracetamol (APAP), la morphine (MO), la dopamine (DA), l'acide ascorbique (AA) et l'acideurique(UA), a donne d'excellents resultats, caracterises par une bonne resolution et une grande separation des pics de potentiel. Les excellentes caracteristiques du composite propose, telles que sa reproductibilite elevee, sa bonne sensibilite, sa selectivite, sa capacite anti-interference et sa bonne stabilite, ont favorise son application a la determination d'autres narcotiques. [Traduit par la Redaction] Mots-cles: tramadol, acide ferrocenecarboxylique, polymere conducteur, tensioactif, morphine, paracetamol., Introduction Tramadol hydrochloride (Tr) is a centrally acting analgesic with opioid agonist properties activating monoaminergic spinal inhibition of pain. Different methods of Tr administration were used, namely orally, rectally, intramuscularly, [...]

Piezoelectricity is pivotal for applications in micro/nanoelectromechanical (MEMS/NEMS) systems. Inducing such a property into the two-dimensional Sc2CTT′ MXenes (where T and T′ are the functionalization atoms) via homogeneous and heterogeneous surface functionalization is explored. The functionalization atoms T and T′ located at the upper and lower surfaces, respectively, are identical in the case of homogeneous functionalization, while they differ in the case of heterogeneous functionalization. Upon T and T′ exchange, an additional reverse heterogeneous configuration is generated. The heterogeneous functionalization of Sc2CT2 induces extraordinary in-plane and out-of-plane piezoelectric effects owing to symmetry breaking. Interestingly, both heterogeneous and its reverse configurations show approximately identical geometrical, energetic, and even elastic properties, but rather different piezoelectric coefficients. The obtained piezoelectric effect is more than ten times larger than the experimentally measured piezoelectricity of a MoS2-monolayer. Our study suggests a way toward more efficient nanoscale piezoelectric devices based on the Sc2C MXenes for energy conversion and storage. [ABSTRACT FROM AUTHOR]