1. Could you explain the significance of your article to the non-specialist? 

The concept of replica is adapted using here the layered double hydroxide, a synthetic anionic clay material, as a structure of sequestration and this allows a fine tuning in the porosity of the resulting carbon as well as a hierarchy in the different domains of porosity. The carbon materials are studied as electric double-layer (EDL) carbon capacitors, the latter being passive components able to supply high power and in the same time benign for the environment (free of undesired metals). The potential applications may be extended to other domains such as those related to hydrogen storage, the environment as scavenger, or catalysis.

2. What has motivated you to conduct this work? 

We were studying the Layered Double Hydroxide as a potential "nano-reactor" for an in situ polymerisation process, and in a second step we were interested to find potential applications for these hybrid inorganic organic assemblies. Furthermore as we are strongly concerned by the topical problems of environment and of energy, we thought that carbon materials presenting high surface area and associated to tunable porosity should be interesting to study. Inspired by the work of Putyera et al. published in the 1990's, we are extending the chemistry and focussing on potential applications due to the present need for new tunable materials.

3. Where do you see this work developing in the future? 

This work and other related work using various molecular anions should be relevant for the electronics technology for which a strong power (>10kWh/kg) is required in a short period of time, as in the case of short power cut for computer and other electronic devices but also in the case of an ignition of an electric vehicle. Taking into account the high surface area, hydrogen storage should also be studied for these replicas. Aside from the applications regarding electrochemical storage, such materials may be interesting in the adsorption of undesired molecules, but also in supported heterogeneous catalysis when the second chemical step, the demineralisation is not complete, and the inorganic part is partially present and dispersed on a carbon matrix.

4. Are there any particular challenges facing future research in this area ? 

The interest of this "replica" route is to give rise to an endless number of carbon materials depending mostly on the nature of the organic source, of the LDH cation composition and layer charge and on the two-step chemical process. Thus the great challenge to target a specific application would be to choose a good candidate among the hybrid precursors and to adapt the chemical process. Finally, in term of performance as EDL's passive component and potential application, one must find a couple LDH / organic molecular assembly which can give rise to carbon materials presenting a capacitance of at least 200 F/g.