Interfacial materials improving stability

The low efficiencies could be due to lack of intimate contact (interface) between the sensitizer (which is hydrophilic) and the spirobifluorene (which is hydrophobic). Moreover, the surface charge also plays a significant role in the regeneration of the dye by the electrolyte.98 In an effort to reduce the charge of the sensitizer and improve the interfacial properties between the surface-bound sensitizer and the spirobifluorene hole-carrier, amphiphilic heteroleptic ruthenium(II) complexes ((48)-(53)) have been used as sensitizers. These complexes show excellent stability and good interfacial properties with hole-transport materials, resulting in improved efficiencies for the solar cells. 

Preferably, the new solvents are also expected to possess better stability or ability in interfacial chemistry on both anode and cathode materials so that the new electrolyte formulation can rely less on EC or they are expected to be less inflammable, as a major shortcoming of the linear carbonates is their low flash points (Tf) (Table 1). In the search for new solvents, fluorination has been adopted as a favorable approach to achieve improvements in these two aspects because the presence of C—F bonds in organic molecules is found to affect interfacial chemistry on carbonaceous anodes in a positive manner,and... 

Fluorocarbons and fluorinated amphiphiles have found a variety of applications in materials science and medicine [1-5]. As many of these applications involve colloidal systems stabilized by a monolayer of fluorinated amphiphiles, it is essential to understand the structure and properties of these interfacial films. Such knowledge can provide improved control over the engineering and properties of highly fluorinated colloids and interfaces [6]. 

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