Environmental and energy sustainability are the core of the European Green Deal. Among sources for efficient and clean energy generation, Hydrogen is looked upon as the next-generation clean-energy carrier. The search for an efficient, operationally convenient and cost-effective material and method for producing renewable hydrogen is needed to realize the “Hydrogen Economy”, i.e. to drive a transition toward clean energy production.
The cost of renewable H2 production is still too high to become competitive, in particular via direct water photolysis, for this reason
the optimization of existing technologies and the design of new materials are fundamental. In this framework, the efforts of the theoretical-computational community are pivotal to discover systems with electro-optical properties tailored to maximize both solar visible light absorption and charge transfer efficiency.
In this scenario, the CoNverSion project faces the scientific and technological challenge of designing innovative materials as building blocks for efficient water photolysis technologies.
A stringent condition for the modelling activity to transfer results to technology applications is the capacity of describing realistic systems, that often are polycrystalline, contain local and extended defects, such as grain boundaries, with local structures size of some tens of nanometers. These systems are hard to describe by only considering perfect ideal bulk or ideal nanostructures few nanometers sized, that are normally used as computational models.
In the CoNverSion project, we propose a refined analysis, by advanced ab-initio methods, of structural, electronic and optical properties of selected transition metal and metal-free oxynitrides, as innovative materials for water photolysis. Despite their potential impact, their theoretical electro-optical characterization is still widely unexplored. We will investigate bulk structures, surfaces and polycrystalline systems through the inclusion of grain boundaries using methods never applied before to these compounds, to identify the best candidate materials for H2 production. Moreover, we will develop specific tools to easily identify
experimental polycrystalline samples eligible for photocatalysis, by establishing a precise link between local chemical properties and spectroscopic signatures of materials.
By combining ab-initio study with the development of sophisticated automated analysis tools, CoNverSion will boost the usage of this still underrated class of materials, paving the way to metal-free oxynitrides.
Noticeably, CoNverSion will not only investigate the fundamental properties of metal oxynitrides but will contribute to filling the gap between material science advancement and engineering applications, thus supporting the technology transfer and future wide-scale energy applications.