New approaches in component design for dye-sensitized solar cells

The present perspective presents a number of issues related to the current direction of DSSC research, with emphasis on the transition from iodide-containing electrolyte to charge-transport media (CTMs), electrolytes or solid-state conductors based on inorganic coordination complexes, aiming to attain a better light-to-electricity conversion efficiency, associated with larger photovoltage, and long-term stability. Such a change necessitates the concomitant introduction of novel dyes and counter electrodes. The first part of the perspective introduces an overview of the DSSC field and a number of considerations related to the transition from the triiodide/iodide-based CTM to CTMs based on alternative systems. Subsequently, the recent developments of CTM based on Cu coordination complexes are discussed, from the inorganic physical chemistry point of view, including some highlights about novel dyes associated to these CTMs. Finally, several preparation methods and applications of different types of novel carbonaceous counter electrode substrates, related to the application of the aforementioned novel CTMs, are presented.