Abstract
Most of human technologies require energy, which has to be converted, stored and released in an efficient and ecological way. Electrochemical energy storage (EES) devices, like batteries and supercapacitors, do that. They convert electrical into chemical energy, and vice versa. Such conversion occurs via redox reactions taking place at electrodes put in contact with an electrolyte. The electrodes’ ability to efficiently exchange electrons and ions at the atomic scale ultimately controls the device performance. Such feature depends on the properties of electrode materials, such as the structure (from the molecular up to the microscale), the redox potentials and the mixed electronic-ionic conductivity. Inorganic lithium-based alloys are common electrodes for batteries, mostly due to their excellent electro-chemical performances. However, they are usually made of toxic elements (cobalt), and their production results in a dramatic carbon footprint. Emerging green alternatives for electrode materials, combining key sustainability and versatility properties, are organic π-conjugated redox materials. They are promising systems for realizing green EES devices (organic batteries), however they underperform with respect to inorganic electrodes. A comprehensive bottom-up investigation correlating the structural and mixed electronic-ionic transport properties at the molecular scale is missing, hindering a major breakthrough for such materials. The project aims at filling this knowledge-gap via a bottom-up strategy encompassing the use of state-of-the-art computational methods, coupled with complementary experimental synthetic approaches and spectroscopic characterization techniques. The goal is to rationalize, model, and predict the complex structure-property relationships ruling the functioning of organic electrodes from the molecular to the microscopic scales. Specifically, the project has three main objectives: 1) unveiling the noncovalent interactions within and between organic conjugated redox systems and metal-/counter-ions, via high-level theoretical and spectroscopic methods, 2) model the solid-state structural and mixed electronic-ionic transport properties, and 3) draw structure-property relationships to design and synthesise high-efficient organic materials for clean-energy EES applications. Such approach is urgent and it has never been accomplished before. The project will therefore go beyond the current schemes, opening new challenges and impacting on interdisciplinary fields, ranging from organic batteries to thermoelectric, biomimetic and neuromorphic applications.
Scientific coordinator of the Department
Daniele Fazzi (Team leader, national coordinator)
Partnership
Università degli studi di Perugia – Dipartimento di Chimica, Biologia e Biotecnologie.