Project Outline


Starting from the second half of the 20th century it has become quite obvious that extensive and efficient use of electrochemical methods for various applications of practical interest (e.g. synthesis of new compounds, energy conversion or electrochemical combustion of organic pollutants) requires novel electrode materials with highly improved features. In an ideal case, such material should fulfill several criteria, some of which may appear at first glance somewhat contradictory. For example, good electrochemical activity is necessary but, at the same time, the electrode material should also exhibit appropriate selectivity for the particular process of interest. Furthermore, high stability (chemical, electrochemical and mechanical) is a prerequisite, but affordable cost is also regarded as highly desirable. The most pragmatic approach (but, from a purely academic point of view, not the most interesting one) to attack these issues is to deposit small particles of electrocatalyst (mainly noble metals or noble metal oxides) on a high surface area support material so that a large number of reaction sites can be provided in a small volume. The material must also be stable and electrically conductive. Until recently, for obvious economical and technological reasons, the most convenient choice for such applications was thought to be granular and pulverulent graphite.

A very modern and much broader concept concerning the role of the substrate on the electrochemical performances of such electrodes emerged from the results of R. Durand et al. evidencing the remarkable and somewhat peculiar electrocatalytic activity of platinum nanoparticles. It was observed, however, that this activity decreases quite dramatically (especially under anodic functioning conditions) due to an irreversible agglomeration of nanoparticles, process that the graphite substrate can hinder to some extent but cannot prevent. It therefore became obvious that extensive use of such electrodes, characterized by the very high degree of dispersion of the electrochemically active particles on the surface, requires support materials that should ensure not only very large specific area but also a certain interactivity. More specifically, a more or less important level of connectivity between the substrate and the deposited particles should exist, with beneficial effects on the general stability and the overall electrochemical performances of the hybrid system. This paradigm shift, attaching to the substrate an importance almost equal to that of the electrocatalyst itself, triggered a very intense research work (mainly based on an Edisonian approach) concerning the possibility and eventual advantages of replacing the conventional graphite support (in its different forms) by other materials, including nanostructured nanoporous carbon, nanotubes pretreated in several ways, oxides, various combinations of conductive polymers, and ceramic materials. Without any systematization (even one which is based upon less rigorous and, perhaps, somewhat controversial criteria), the huge amount of experimental data from literature (obtained for a large variety of support materials and electrochemical processes) is a major obstacle when aiming to crystallize at least partial conclusions or to get a general picture of the present stage of knowledge in this field. In a promising approach to this problem we shall further assume that the influence of the substrate on the overall electrochemical properties of the micro and nanostructured deposits manifests itself in “interactional effects” and/or “functional effects”. Even though these syntagmas may induce a certain level of arbitrariness they could be used, at least in our opinion, as a basis for a simple, straightforward classification of substrate contributions, despite their apparently eclectic character.

This project aims at systematically put into evidence interactional and functional effects of the substrate on the electrochemical performances of metallic (Pt) and oxidic (e.g., TiO2, RuO2, Co3O4) particles, estimated and quantified from their activity for O2 evolution and CH3OH oxidation. The choice of such materials (intensively studied in literature) and that of typical processes is justifiable because it allows focusing on the effects of the substrate, by avoiding the need for large amount of data on the electroactive material itself. A critical comparison of the results with those reported in literature will allow elucidating (at least partially) some controversial or contradictory aspects of the electrochemical properties of these materials. An important ab initio simplification results from the use of boron-doped diamond (BDD) as a substrate for electroactive particles. This enables neglecting capacitive and pseudo-capacitive influences, due to the outstanding features of BDD: low background current, high stability, and inertness to adsorption. The high overpotential for O2 evolution and the lack of activity for alcohols anodic oxidation are, in the context of this project, additional advantages. Since the influence of the substrate will be rather negligible, a more straightforward correlation between the specific properties of the deposited material and the overall electrochemical activity of the electrode system is expected.


Main Objectives



Research Team


Dr. Nicolae Spătaru Senior researcher
Dr. Maria Marcu Senior researcher
Dr. Tanţa Spătaru Senior researcher
Dr. Fănică Cimpoeşu Senior researcher
Dr. Petre Osiceanu Senior researcher
Dr. Cecilia Lete Senior researcher
Dr. Cornel Munteanu Senior researcher
Chem. Alina Lupu Master student
Eng. Alexandru I. Căciuleanu Master student

Contact: nspataru@icf.ro