During the first half of the project, we have made advances on important fronts:
(1) Setting up of lab facilities. We have set the facilities to handle air-sensitive chemicals, especially a glovebox specifically modified to enable sample preparation (ball milling, pressing, arc welding). We have also developed procedures for the preparation of important chemical reagents based on highly reactive silicon species. Besides, we have developed protocols enabling to use high pressures to trigger phase transformations into nanoparticles, including diamond anvil cells.
(2) In situ devices. We have designed a new device enabling to probe in situ chemical reactions in inorganic molten salts between 200 and 1000 °C, the conditions of formation of some gem stones and of the new materials we are targeting. This oven provides access to multiple techniques based on synchrotron radiation for addressing the way matter transforms in these geo-inspired conditions. We have also developed a method to understand the nature and evolution of the active species operating in nanomaterials during their use in electrocatalytic energy conversion. This approach combines state-of-the-art analytical transmission electron microscopy and in situ synchrotron radiation-based spectroscopy. We have successfully applied this method to multi-element catalysts of electrocatalytic water splitting for H2 production and unveiled unexpected redox switches during the operation of these nanomaterials.
(3) Synthesis of new nanomaterials. We have developed the methodology proposed in GENESIS to reach new nanomaterials. Among the achievements on materials synthesis, our first highlight is the design of a pathway to design multimetallic silicide nanocrystals by reacting silicon nanoparticles in molten salts. These nanomaterials exhibit high performances for electrocatalytic water oxidation, a key reaction for the production of hydrogen from water. The second highlight is the discovery of a new compound made of two different anions and built from a molten salt as a totally new crystal structure, which shows significant activity for hydrogen production from photocatalytic water splitting.
(4) Coining an interdisciplinary field of chemical synthesis. We have defined the foundations of geo-inspired materials synthesis, the concept underlying the GENESIS project, and the first results, through several publications and communications in international conferences.
