Recent advances in the electrooxidation of biomass-based organic molecules for energy, chemicals and hydrogen production

The recent developments in biomass-derivative fuelled electrochemical converters for electricity or hydrogen production together with chemical electrosynthesis have been reviewed.

Surface Structure Characterization of Shape and Size Controlled Pd Nanoparticles by Cu UPD: A Quantitative Approach

The search for new surface sensitive probes that characterize the surface structure of shape and size-controlled nanoparticles is an interesting topic to properly understand the correlations between electrocatalytic properties and surface structure at the nanoscale. Herein, we report the use of Cu UPD to characterize, not only qualitatively but also quantitatively, the surface structure of different Pd nanoparticles with controlled particle shape and size. Thus, Pd nanoparticles with cubic, octahedral and rhombic dodecahedral shapes, that is, with preferential {100}, {111}, and {110} surface structures, respectively, were prepared. In addition, cubic Pd nanoparticles with different particles sizes and spherical (2–3 nm) Pd nanoparticles were also synthesized. Based on the Cu UPD results on Pd single crystals, a new approach is proposed to qualitatively and quantitatively determine the percentages of {100}, {111}, and {110} surface domains present at the surface of the different shape and size controlled Pd nanoparticles. The results reported clearly show the benefits of this Cu UPD to get detailed information of the surface structure of the nanoparticles according to their particle shape and size.

Shape-Controlled Nanoparticles as Anodic Catalysts in Low-Temperature Fuel Cells

The great dependence of the electrocatalytic activity of most electrochemical reactions on the catalytic surface area and specific surface structure is widely accepted. Building on the extensive knowledge already available on single-crystal surfaces, this Perspective discusses the recent progress made in low-temperature fuel cells through the use of the most active shape-controlled noble metal-based nanoparticles. In particular, we will focus on discussing structure-composition-reactivity correlations in methanol, ethanol, and formic acid oxidation reactions and will offer a general vision of future needs.

Shape-controlled metal nanoparticles for electrocatalytic applications

The application of shape-controlled metal nanoparticles is profoundly impacting the field of electrocatalysis. On the one hand, their use has remarkably enhanced the electrocatalytic activity of many different reactions of interest. On the other hand, their usage is deeply contributing to a correct understanding of the correlations between shape/surface structure and electrochemical reactivity at the nanoscale. However, from the point of view of an electrochemist, there are a number of questions that must be fully satisfied before the evaluation of the shaped metal nanoparticles as electrocatalysts including (i) surface cleaning, (ii) surface structure characterization, and (iii) correlations between particle shape and surface structure. In this chapter, we will cover all these aspects. Initially, we will collect and discuss about the different practical protocols and procedures for obtaining clean shaped metal nanoparticles. This is an indispensable requirement for the establishment of correct correlations between shape/surface structure and electrochemical reactivity. Next, we will also report how some easy-to-do electrochemical experiments including their subsequent analyses can enormously contribute to a detailed characterization of the surface structure of the shaped metal nanoparticles. At this point, we will remark that the key point determining the resulting electrocatalytic activity is the surface structure of the nanoparticles (obviously, the atomic composition is also extremely relevant) but not the particle shape. Finally, we will summarize some of the most significant advances/results on the use of these shaped metal nanoparticles in electrocatalysis covering a wide range of electrocatalytic reactions including fuel cell-related reactions (electrooxidation of formic acid, methanol and ethanol and oxygen reduction) and also CO2 electroreduction.

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Hierarchical self-assembly of random mica nanosheet-stabilized silver nanoparticles into flower microstructures for highly sensitive SERS substrates

The use of self-assembled novel flower-like microstructures as SERS substrates allowed high-efficiency detection of adenine molecules from DNA.