Publications by authors named "Samuel Ntim"

We present here a detailed analysis of the electric double layer at the gold electrode/[BMIM][BF] interface using a polarizable model for the electrode, based on our recent approach to include image charges [Geada et al. 716]. A double bell (camel) shape is obtained for the differential capacitance, where the inclusion of metal polarization allows for a higher density of ions in the double layer, particularly around the maxima, thereby increasing the capacitance.

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Understanding electrified interfaces requires an accurate description of the electric double layer which also takes into account the metal polarisation. Here we present a simple approach to the molecular dynamics simulation of electrified interfaces which combines fixed charges and a core-shell model for the description of the polarisable electron density on the metal electrode. The approach has been applied to the Au(111) surface in contact with a NaCl aqueous electrolyte solution in order to calculate the differential capacitance and to gain a detailed picture of the charging mechanism.

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It has been shown that a weak shear can induce crystallisation in a disordered, glassy state. In this study, we use molecular dynamics simulations in order to investigate the out-of-equilibrium properties of [BMIM][BF] confined between metal slabs. In particular, we want to understand the extent to which the shear flow modifies the interfacial properties.

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The use of biomolecules as capping and reducing agents in the synthesis of metallic nanoparticles constitutes a promising framework to achieve desired functional properties with minimal toxicity. The system's complexity and the large number of variables involved represent a challenge for theoretical and experimental investigations aiming at devising precise synthesis protocols. In this work, we use L-asparagine (Asn), an amino acid building block of large biomolecular systems, to synthesise gold nanoparticles (AuNPs) in aqueous solution at controlled pH.

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The peculiar properties of ionic liquids in confinement have not only become essential for energy storage, catalysis and tribology, but still pose fundamental questions. Recently, an anomalous liquid-solid phase transition has been observed in atomic force microscopy experiments for 1-butyl-3-methylimidazolium tetrafluoroborate ([BMIM][BF]), the transition being more pronounced for metallic surfaces. Image charges have been suggested as the key element driving the anomalous freezing.

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