In situ synchrotron-based techniques are starting to be intensively exploited to investigate a range of electrochemical systems; in particular, X-ray photoelectron spectroscopy (XPS), owing to its utmost surface sensitivity and photon-in/electron-out nature, has been recognized as a powerful tool to achieve insight into phenomena occurring at the electrode surface and at the electrode/electrolyte interface of solid oxide–based electrochemical devices, in the presence of a reactive gas and under applied electrochemical polarization. Conventional XPS exhibits the key limitation of extensive space averaging that results in missing important details of the morphochemical structure of the materials forming the electrochemical device, that, instead, have a notable impact on electrocatalytic performance and durability. For this reason, combining the analytical power of XPS with space-resolution capability can provide unique and practically useful insight for the understanding and improvement of electrochemical devices. In this chapter, we focus on in situ XPS microspectroscopy, enabling elemental and chemical state mapping with high spatial resolution under electrochemical operating conditions. Specifically, we describe our recent work on a range of solid oxide fuel cell materials and configurations, performed with reactive gases and gas mixtures both in high-vacuum and near-ambient pressure conditions This chapter includes on the one hand details of instrumental solutions regarding cell engineering, gas feed modes, and pressure management, and on the other hand, a representative selection of the kind of electrochemical information that can be drawn from photoelectron microspectroscopy.
In situ photoelectron spectromicroscopy for the investigation of solid-oxide based electrochemical systems
Benedetto Bozzini;
2020-01-01
Abstract
In situ synchrotron-based techniques are starting to be intensively exploited to investigate a range of electrochemical systems; in particular, X-ray photoelectron spectroscopy (XPS), owing to its utmost surface sensitivity and photon-in/electron-out nature, has been recognized as a powerful tool to achieve insight into phenomena occurring at the electrode surface and at the electrode/electrolyte interface of solid oxide–based electrochemical devices, in the presence of a reactive gas and under applied electrochemical polarization. Conventional XPS exhibits the key limitation of extensive space averaging that results in missing important details of the morphochemical structure of the materials forming the electrochemical device, that, instead, have a notable impact on electrocatalytic performance and durability. For this reason, combining the analytical power of XPS with space-resolution capability can provide unique and practically useful insight for the understanding and improvement of electrochemical devices. In this chapter, we focus on in situ XPS microspectroscopy, enabling elemental and chemical state mapping with high spatial resolution under electrochemical operating conditions. Specifically, we describe our recent work on a range of solid oxide fuel cell materials and configurations, performed with reactive gases and gas mixtures both in high-vacuum and near-ambient pressure conditions This chapter includes on the one hand details of instrumental solutions regarding cell engineering, gas feed modes, and pressure management, and on the other hand, a representative selection of the kind of electrochemical information that can be drawn from photoelectron microspectroscopy.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
