Richard G. Compton

Carbon-free energy: a review of ammonia- and hydrazine-based electrochemical fuel cells

Most low-temperature fuel cells are based on the hydrogen fuel cell in some form, with its high power density and clean oxidation to yield no carbon-containing products. However, due to issues of compression and storage, research has been on-going into alternative “hydrogen-storage” compounds that can deliver similar performance in a more convenient form. The nitrogen hydrides, ammonia and hydrazine, have been candidate materials for fuels for nearly 50 years, but rapid advances in the past 5–6 years have shown them to be front-runners in the race for commercial, high-performance, portable fuel cells. In this review, we briefly summarise the recent advances in ammonia and hydrazine fuel cells.

Determining unknown concentrations of nanoparticles: the particle-impact electrochemistry of nickel and silver

The developing field of particle-impact electrochemistry is rapidly establishing itself as a powerful tool for the interpretation of a wide range of phenomena associated with nanoparticles. In this article we present results showing the characterisation of nickel nanoparticles and, for the first time, a mixture of nanoparticles: in this case nickel and silver. The former are shown not to aggregate in aqueous solution whereas the latter do. We report a novel method for the determination on unknown concentrations of nanoparticles in a sample and demonstrate its use for both aggregating and non-aggregating nanoparticles.

Electrochemical Sizing of Organic Nanoparticles

The size of organic nanoparticles (NPs) can be electrochemically determined by Faradaic charge transfer when nanoparticles strike an electrode. Indigo NPs were used as a model (see distribution of the NP diameter). This strategy could be used for monitoring the size of a wide range of organic nanoparticles.

Making contact: charge transfer during particle–electrode collisions

The study of impact processes between particles and electrode surfaces is less than 20 years old, and has recently received added impetus due to the current intense interest in the chemistry of nanoparticles. In this review, we briefly appraise the historical results and recent developments in this field, and consider its potentially wide-ranging applications.

The electrochemical detection of tagged nanoparticles via particle-electrode collisions: Nanoelectroanalysis beyond immobilisation

The use of particle-impact coulometry in identifying and quantifying nanoparticles tagged (or labelled) with electroactive molecules is demonstrated via the detection of 1,4-nitrothiophenol-tagged silver nanoparticles in aqueous dispersion at potentials more negative than -0.17 V (vs. Ag/AgCl, the reduction potential of nitrothiophenol) via monitoring of particle-electrode collisions.