Hybrid Materials Approach In The Design Of Electrodes And Electrolytes For Energy Storage And Conversion
- PDF / 244,941 Bytes
- 8 Pages / 612 x 792 pts (letter) Page_size
- 26 Downloads / 248 Views
EE12.4.1
Hybrid Materials Approach In The Design Of Electrodes And Electrolytes For Energy Storage And Conversion Karina Cuentas-Gallegos, Mónica Lira-Cantú, Nieves Casañ-Pastor, Juan A. Asensio, Pedro Gómez-Romero* Materials Science Institute of Barcelona (CSIC), Campus UAB, 08193 Bellaterra, Barcelona, Spain. *E-mail: [email protected]
ABSTRACT The integration of electro-ionically active inorganic species in polymer matrices allows for the design of either electrode or electrolyte materials depending on the conducting or insulating properties of the polymer used. Conducting polymers can be used as the basis for a variety of hybrid electrode systems, whereas other polymers such as polybenzimidazoles have been used as electrolyte membranes by themselves or in combination with inorganic solid acids. We will discuss the general approach of hybrid design with this in mind and specifically we will describe our recent results on the use of polyoxometalate-containing hybrids in energy storage and conversion devices. In this respect we have worked in our laboratory on electrochemical supercapacitors and fuel cells but emphasis should be made on the broader potential fields of application of this type of materials.
INTRODUCTION Polyoxometalates have been known and used within the field of molecular inorganic chemistry for nearly two hundred years , but only recently are they being recognized as useful building blocks for the design of materials. Indeed, with the turn of the century, the coming of age of materials science and the advent of nanotechnology, polyoxometalates are beginning to be recognized as unique chemical species that could turn from very special molecules to very useful materials. As a matter of fact, one of the main reasons why polyoxometalates have not been considered in the past for the design of functional materials is precisely because their molecular nature makes them soluble in water and common organic solvents. Yet, they not only share topological and structural features with related transition metal oxides but also resemble them concerning their redox, electronic and ionic transport behavior.[1,2] In all these respects, polyoxometalates can be generically considered as the perfect models for quantum-sized transition metal oxide nanoparticles.[3,4] For example, the electrochemical or photochemical injection of electrons in heteropolyanions (HPA) with the concomitant induction of thermally activated delocalization between metal centers and IVCT bands leading to change in color parallel the corresponding electrochromic properties of the corresponding oxides upon doping. On the other hand, POMs are ultimately dispersed species where most, if not all the metal centers that conform the cluster are not part of a bulk extended structure but are effectively surface ions, with all the implications this has concerning interfacial chemistry/electrochemistry and surface properties.
EE12.4.2
The intrinsic properties of polyoxometalates are therefore of interest in themselves not only from a fundamental p
Data Loading...
