This three-year project is concerned with: i) the development of novel proton conductors for use in intermediate-temperature fuel cells (IT-PCFC), and ii) the assembly and electrochemical characterization of complete devices. Efficient and clean energy generation is a key concept of future sustainable development, encompassing the issues of natural resources exploitation and air pollution. For this reason, fuel cells fed with hydrogen from renewable sources are at the forefront of contemporary energy research. The widespread diffusion of fuel cells, however, has come at a standstill due to several factors, most importantly the absence of one viable trade-off between high fuel efficiency and material costs. In fact, the low-temperature (<100C) polymer electrolyte membrane (PEM) fuel cells need expensive noble metal catalysts as electrodes, and the high-temperature (>700C) solid-oxide fuel cells (SOFC) present a number of technological issues (thermal and mechanical stress, quick degradation, limited portability). The so-called "temperature gap" between the operating temperatures of these two devices (100 - 700 °C) has effectively hindered fuel cell development in the last decade. In order to investigate the feasibility of exploring a new temperature range for fuel cells, novel materials and new approaches based on innovative techniques for this field have to be introduced. In this framework, primary aims of this project are: - development and optimization of ceramic electrolytes for IT-PCFC working at 400-600 °C, in terms of composition, morphology, sinterability and conductivity; - design of inorganic-organic hybrid materials based on the covalent functionalization of inorganic oxides with organic molecules and chains, and the preparation of electrolyte membranes with: a) higher thermal resistance with respect to polymer electrolytes (up to 300 °C); b) high proton conductivity and chemical stability in operating conditions; - fabrication, functional, structural and microstructural characterization of complete fuel cells based on the above electrolytes. Research activities involve a combined experimental-computational approach, from the theoretical prediction of properties to the device assembly, and including a complete structural, microstructural and functional characterization. These activities will be carried out concurrently for ceramic oxides and inorganic-organic hybrids. The core of the project concerns the development of electrolytes, but part of the activity will also be devoted to obtain suitable electrode materials in order to maximize the final efficiency. For each topic, conventional synthesis (solid-state reaction) and innovative preparation methods (wet chemistry) will both be envisaged. By this way, products with different features will be obtained to study the microstructural and functional properties relations. Several characterization techniques will be employed, for both powders and membranes. Together with routinary characterization to be carried out in the laboratory (structural, thermal, physico-chemical and chemical stability), advanced structural techniques will be used for the study of long-range and short-range structure: these include solid-state NMR, as well as X-ray and neutron techniques available in large-scale facilities. To complement the experimental techniques, multiscale computational modeling will be extensively used (ab initio quantum chemistry, semiempirical atomistic simulazions, defect modeling), to provide feedback to synthesis and improve the understanding of the transport mechanisms and of the overall functional properties of the materials. The complete cells will be anode-supported in order to minimize the electrolyte resistance, and to optimize efficiency. Different deposition techniques (WPS, RF sputtering, layer-by-layer, spin coating) will be employed to control the thickness of electrolyte layers, and will be developed ad hoc for hybrid materials. Electrochemical characterization will be carried out with impedance spectroscopy and e.m.f. measurements on symmetrical cells, to study single materials, and also with polarization curves on complete cells. Prolonged electrochemical tests (up to 1000 hours) will be followed by an ad hoc innovative microstructural characterization of the electrode-electrolyte interface using synchrotron radiation. The activities involve three research units (UR1 = UNIPV, UR2 = UNIPA, UR3 = CNR-IENI), and require extensive cooperation between units. Further collaborations with Italian and foreign scientific institutions will be employed specifically for this project: in particular, computational simulations will benefit from collaborations with prof. M.S. Islam (University of Bath, UK) and prof. C. Adamo (Ecole nationale supérieure de chimie de Paris, FR); solid-state NMR characterization will be carried out in collaboration with dr. G. Pintacuda (Ecole Normale Supérieure de Lyon, FR); microstructural characterization of ceramic materials will be carried out in collaboration with prof. A. Thorel (ARMINES, Centre des Materiaux, Evry, FR) and the development of hybrid materials will be carried out in collaboration with dr. S. Gross (ISTM-CNR, Padova, IT). The Research Units involved are expert in the field of fuel cells, and they will combine complementary expertise in the field of design and development of the materials under investigation. The close collaboration among the research groups directly involved in the project and the external collaborations will contribute to the improvement of the scientific excellence at a fundamental level and strengthen the ability to produce innovation, in agreement with the Horizon 2020 priorities. Moreover, the project aims at implementing knowledge and expertise at a more technological level, in order to reach the fabrication of prototype cells suited for technological use and protected by patents.
Il presente progetto triennale riguarda lo sviluppo di nuovi conduttori protonici per celle a combustibile operanti a temperature intermedie (IT-PCFC), e l'assemblaggio e la caratterizzazione elettrochimica dei dispositivi completi. La produzione di energia pulita in maniera efficiente è un concetto chiave dello sviluppo futuro sostenibile, che include i problemi di sfruttamento delle risorse naturali e l'inquinamento atmosferico. Per questo motivo, le celle a combustibile alimentate con idrogeno da fonti rinnovabili sono all'avanguardia della ricerca energetica contemporanea. La diffusione delle celle a combustibile, tuttavia, è arrivata a un punto morto a causa di diversi fattori, il più importante dei quali è l'assenza di un valido compromesso tra efficienza del carburante e costo dei materiali. Infatti, le celle a combustibile a membrana elettrolitica polimerica (PEM), che lavorano a bassa temperatura (<100C), necessitano di catalizzatori a metalli nobili molto costosi come elettrodi, e le celle a combustibile a ossidi solidi (SOFC), che lavorano ad alta temperatura (>700C), presentano una serie di problemi tecnologici (sollecitazioni termiche e meccaniche, veloce degradazione , portabilità limitata). Il cosiddetto "salto di temperatura" tra le temperature di esercizio di questi due dispositivi (100 - 700 ° C) ha in pratica impedito lo sviluppo delle cellule combustibile nell'ultimo decennio. Per esplorare la possibilità di avere celle a combustibile operanti a temperature intermedie, è necessario introdurre nuovi materiali e approcci basati su tecniche innovative per il settore. In questo contesto, gli obiettivi generali del progetto sono: - lo sviluppo e l'ottimizzazione in termini di composizione, morfologia, microstruttura e conducibilità, di elettroliti ceramici per IT-PCFC operanti nell'intervallo di temperatura 400-600 °C; - la progettazione di materiali ibridi inorganici-organici, basati sulla funzionalizzazione covalente di ossidi inorganici con catene e molecole organiche, e la preparazione di membrane elettrolitiche che mostrino: a) maggiore resistenza termica rispetto agli elettroliti polimerici (fino a 300 °C); b) alta conducibilità protonica e stabilità chimica in condizioni operative; - la fabbricazione e la caratterizzazione funzionale e microstrutturale di celle a combustibile complete basate sugli elettroliti suddetti. L'attività di ricerca prevede un approccio combinato sperimentale-computazionale, che partendo dalla previsione teorica delle proprietà dei materiali giunga alla loro sintesi, all'assemblaggio e alle relative indagini microstrutturali e funzionali di un dispositivo funzionante. Queste attività saranno portate avanti parallelamente per ossidi ceramici e ibridi inorganici-organici. La parte centrale del progetto verterà sullo sviluppo di elettroliti, ma verrà posta attenzione anche alla scelta di opportuni elettrodi per ottimizzare l'efficienza dei dispositivi. Per ognuno di questi ambiti il progetto prevede l'applicazione di tecniche di sintesi tradizionali (sintesi a stato solido) e innovative (sintesi di "wet chemistry"). In questo modo si otterranno prodotti con caratteristiche diverse, per uno studio delle relazioni fra proprietà microstrutturali e funzionali. Verranno impiegate diverse tecniche di caratterizzazione strutturali e funzionali, sia per polveri che per membrane. Parallelamente alla caratterizzazione routinaria di laboratorio (strutturale, termica, chimico-fisica e di stabilità chimica), verranno usate estesamente tecniche strutturali avanzate per lo studio della struttura a corto raggio e a lungo raggio, tra cui NMR a stato solido, spettroscopia/diffrazione di raggi X con luce di sincrotrone, e diffrazione di neutroni. A complemento delle tecniche sperimentali, è previsto un ampio utilizzo di simulazioni computazionali a livelli differenti (chimica quantistica ab initio, simulazioni semiempiriche statiche e dinamiche, modellazione dei difetti), con il duplice scopo di indirizzare le sintesi e l'ottimizzazione dei materiali e di aiutare la comprensione dei meccanismi di migrazione e quindi l'interpretazione delle proprietà funzionali. L'architettura delle celle complete sarà preferibilmente di tipo anodo-supportante per minimizzare la resistenza dello strato di elettrolita e migliorare così le prestazioni. Varie tecniche di deposizione (WPS, sputtering, layer-by-layer, spin coating), eventualmente sviluppate appositamente per i materiali ibridi, permetteranno di controllare lo spessore degli strati elettrolitici. La caratterizzazione elettrochimica verrà effettuata con spettroscopia di impedenza ed e.m.f. su celle simmetriche, per lo studio dei singoli materiali, e anche con curve di polarizzazione su celle complete. I test elettrochimici prolungati (fino a 1000 ore) saranno seguiti da una caratterizzazione microstrutturale innovativa dell'interfaccia elettrodo-elettrolita con luce di sincrotrone, sfruttando setup sperimentali sviluppati ad hoc. L'attività di ricerca coinvolge tre unità (UR1 = UNIPV, UR2 = UNIPA, UR3 = CNR-IENI), e richiede una estesa collaborazione fra le unità. Ulteriori collaborazioni con istituzioni italiane e straniere saranno impiegate specificamente per questo progetto: in particolare, le attività di simulazione beneficeranno della collaborazione del prof. M.S. Islam (University of Bath, UK) e del prof. C. Adamo (Ecole nationale supérieure de chimie de Paris, FR); la caratterizzazione tramite NMR a stato solido sarà condotta in collaborazione con il dr. G. Pintacuda (Ecole Normale Supérieure de Lyon, FR); la caratterizzazione microstrutturale dei materiali ceramici sarà svolta in collaborazione con il Prof. A. Thorel (ARMINES, Centre des Materiaux, Evry, FR) e lo sviluppo di materiali ibridi inorganici-organici sarà condotto in collaborazione con la dr.ssa S. Gross (ISTM-CNR, Padova, IT). Le Unità di Ricerca coinvolte sono esperte nel campo delle celle a combustibile, e sapranno combinare le loro competenze complementari nel campo del design e dello sviluppo dei materiali oggetto di indagine. La stretta collaborazione fra i gruppi di ricerca direttamente coinvolti nel progetto e i collaboratori esterni contribuiranno a migliorare l'eccellenza scientifica a livello ricerca di base e a rafforzare la capacità di produrre innovazione, in accordo con le priorità di Horizon 2020. Inoltre, il progetto si prefigge l'implementazione di conoscenze e competenze ad un livello più tecnologico, per raggiungere la fabbricazione di un prototipo di cella a combustibile adatta per uso tecnologico e protetta da brevetti.
INCYPIT - Materiali ceramici e ibridi innovativi per celle a combustibile a conduzione protonica operanti a temperature intermedie: progettazione, caratterizzazione e assemblaggio del dispositivo
G Canu;
2012
Abstract
This three-year project is concerned with: i) the development of novel proton conductors for use in intermediate-temperature fuel cells (IT-PCFC), and ii) the assembly and electrochemical characterization of complete devices. Efficient and clean energy generation is a key concept of future sustainable development, encompassing the issues of natural resources exploitation and air pollution. For this reason, fuel cells fed with hydrogen from renewable sources are at the forefront of contemporary energy research. The widespread diffusion of fuel cells, however, has come at a standstill due to several factors, most importantly the absence of one viable trade-off between high fuel efficiency and material costs. In fact, the low-temperature (<100C) polymer electrolyte membrane (PEM) fuel cells need expensive noble metal catalysts as electrodes, and the high-temperature (>700C) solid-oxide fuel cells (SOFC) present a number of technological issues (thermal and mechanical stress, quick degradation, limited portability). The so-called "temperature gap" between the operating temperatures of these two devices (100 - 700 °C) has effectively hindered fuel cell development in the last decade. In order to investigate the feasibility of exploring a new temperature range for fuel cells, novel materials and new approaches based on innovative techniques for this field have to be introduced. In this framework, primary aims of this project are: - development and optimization of ceramic electrolytes for IT-PCFC working at 400-600 °C, in terms of composition, morphology, sinterability and conductivity; - design of inorganic-organic hybrid materials based on the covalent functionalization of inorganic oxides with organic molecules and chains, and the preparation of electrolyte membranes with: a) higher thermal resistance with respect to polymer electrolytes (up to 300 °C); b) high proton conductivity and chemical stability in operating conditions; - fabrication, functional, structural and microstructural characterization of complete fuel cells based on the above electrolytes. Research activities involve a combined experimental-computational approach, from the theoretical prediction of properties to the device assembly, and including a complete structural, microstructural and functional characterization. These activities will be carried out concurrently for ceramic oxides and inorganic-organic hybrids. The core of the project concerns the development of electrolytes, but part of the activity will also be devoted to obtain suitable electrode materials in order to maximize the final efficiency. For each topic, conventional synthesis (solid-state reaction) and innovative preparation methods (wet chemistry) will both be envisaged. By this way, products with different features will be obtained to study the microstructural and functional properties relations. Several characterization techniques will be employed, for both powders and membranes. Together with routinary characterization to be carried out in the laboratory (structural, thermal, physico-chemical and chemical stability), advanced structural techniques will be used for the study of long-range and short-range structure: these include solid-state NMR, as well as X-ray and neutron techniques available in large-scale facilities. To complement the experimental techniques, multiscale computational modeling will be extensively used (ab initio quantum chemistry, semiempirical atomistic simulazions, defect modeling), to provide feedback to synthesis and improve the understanding of the transport mechanisms and of the overall functional properties of the materials. The complete cells will be anode-supported in order to minimize the electrolyte resistance, and to optimize efficiency. Different deposition techniques (WPS, RF sputtering, layer-by-layer, spin coating) will be employed to control the thickness of electrolyte layers, and will be developed ad hoc for hybrid materials. Electrochemical characterization will be carried out with impedance spectroscopy and e.m.f. measurements on symmetrical cells, to study single materials, and also with polarization curves on complete cells. Prolonged electrochemical tests (up to 1000 hours) will be followed by an ad hoc innovative microstructural characterization of the electrode-electrolyte interface using synchrotron radiation. The activities involve three research units (UR1 = UNIPV, UR2 = UNIPA, UR3 = CNR-IENI), and require extensive cooperation between units. Further collaborations with Italian and foreign scientific institutions will be employed specifically for this project: in particular, computational simulations will benefit from collaborations with prof. M.S. Islam (University of Bath, UK) and prof. C. Adamo (Ecole nationale supérieure de chimie de Paris, FR); solid-state NMR characterization will be carried out in collaboration with dr. G. Pintacuda (Ecole Normale Supérieure de Lyon, FR); microstructural characterization of ceramic materials will be carried out in collaboration with prof. A. Thorel (ARMINES, Centre des Materiaux, Evry, FR) and the development of hybrid materials will be carried out in collaboration with dr. S. Gross (ISTM-CNR, Padova, IT). The Research Units involved are expert in the field of fuel cells, and they will combine complementary expertise in the field of design and development of the materials under investigation. The close collaboration among the research groups directly involved in the project and the external collaborations will contribute to the improvement of the scientific excellence at a fundamental level and strengthen the ability to produce innovation, in agreement with the Horizon 2020 priorities. Moreover, the project aims at implementing knowledge and expertise at a more technological level, in order to reach the fabrication of prototype cells suited for technological use and protected by patents.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
