Realistic Modelling of Dynamics at Nanostructured Interfaces Relevant to Heterogeneous Catalysis

The focus of this short review is directed towards investigations of the dynamics of nanostructured metallic heterogeneous catalysts and the evolution of interfaces during reaction—namely, the metal–gas, metal–liquid, and metal–support interfaces. Indeed, it is of considerable interest to know how a metal catalyst surface responds to gas or liquid adsorption under reaction conditions, and how its structure and catalytic properties evolve as a function of its interaction with the support. This short review aims to offer the reader a birds-eye view of state-of-the-art methods that enable more realistic simulation of dynamical phenomena at nanostructured interfaces by exploiting resource-efficient methods and/or the development of computational hardware and software.

Electrochemical Study of Butyl-Pyrene Nitrobenzoate Derivatives Trapped on MWCNT Nanostructured Electrodes

In the scope of our studies tending to find new nanostructured electrodic platforms containing nitroaromatic compounds (NACs) capable of generating in situ electrocatalytic redox couples, we synthesized and electrochemically studied three related 4-(pyren-1-yl)-butyl-substituted nitrobenzoates (2-NBPy, 3-NBPy and 4-NBPy). The design of the compounds is based on a combination of a) an adsorptive tail (-butyl-pyrene) capable of interacting via π-π stacking with the MWCNT nanostructured electrodes and b) nitroaromatic compounds (NACs) capable of electrochemically activating to form a RNHOH/NO redox couple trapped on the nanostructured electrodic platform. Morphological and structural analyses of the nanostructured interfaces were performed by SEM and WAXS/SAXS analysis. All of the NBPy compounds trapped on the nanostructured electrodic platform were susceptible to reduction, generating the corresponding hydroxylamine derivative. The order of ease of reduction for the nitrocompounds is 4-NBPy > 2-NBPy > 3-NBPy. After electrochemical activation, all compounds generated an RNHOH/NO redox mediator couple with the following order of stability of the mediator couple: 2-NBPy > 3-NBPy > 4-NBPy. For the 2-NBPy and 3-NBPy derivatives, excellent stability of the couple was observed, and a decrease in the peak current of 6% was observed after 60 minutes.

Probing Biosensing Interfaces With Single Molecule Localization Microscopy (SMLM)

Far field single molecule localization microscopy (SMLM) has been established as a powerful tool to study biological structures with resolution far below the diffraction limit of conventional light microscopy. In recent years, the applications of SMLM have reached beyond traditional cellular imaging. Nanostructured interfaces are enriched with information that determines their function, playing key roles in applications such as chemical catalysis and biological sensing. SMLM enables detailed study of interfaces at an individual molecular level, allowing measurements of reaction kinetics, and detection of rare events not accessible to ensemble measurements. This paper provides an update to the progress made to the use of SMLM in characterizing nanostructured biointerfaces, focusing on practical aspects, recent advances, and emerging opportunities from an analytical chemistry perspective.