Solar cells photovoltaic performance stability

As mentioned earlier, the DSSC is a very attractive and promising device for solar cell applications that has been intensively investigated worldwide, and its photovoltaic mechanism has also intensively investigated [11-20]. Moreover, commercial applications of the DSSC have been under investigation. In this chapter, we describe the DSSC, including its component materials, structure, working mechanism, efficient preparation procedure, current researches, and long-term stabilities. We also introduce the subjects for improvement of its performance and commercial applications. 

The promise of photoelectrochemical devices of both the photovoltaic and chemical producing variety has been discussed and reviewed extensively.Cl,, 3,4) The criteria that these cells must meet with respect to stability, band gap and flatband potential have been modeled effectively and in a systematic fashion. However, it is becomirg clear that though such models accurately describe the general features of the device, as in the case of solid state Schottky barrier solar cells, the detailed nature of the interfacial properties can play an overriding role in determining the device properties. Some of these interface properties and processes and their potential deleterious or beneficial effects on electrode performance will be discussed. 

Gratzel M. (2006), Photovoltaic performance and long-term stability of dye-sensitized mesosocopic solar cells , Comptes Rend. Chimie 9, 578-583. 

The appearance of these aggregates does not hamper photovoltaic performance of the fullerene/P3HT blends short-circuit currents and FFs of the devices become even improved in some cases. This behavior makes a sharp contrast with the MDMO-PPV/[60]PCBM and P3HT/[60]PCBM systems described above where the formation of numerous PCBM aggregates in the films immediately kills their photovoltaic performance. It might be envisioned that solar cells comprising thiophene or furane-appended fullerene derivatives (I-III) exhibit superior thermal stability because of hampered fullerene/ polymer segregation. Unfortunately, this issue was not addressed in this study. 

The photovoltaic performance of DSSC can be analyzed in terms of conversion yield and long-term stability. For metal complex-based DSSCs, the polypyridyl complexes of ruthenium and osmium are known to fulfill both criteria [29]. After the solar cell has been fabricated, it has to be evaluated for a number of parameters such as IPCE (or quantum efficiency), /sc (short-circuit current), Voc (open-circuit voltage), FF (fill factor), and rj (power conversion efficiency), which provide performance information for real-world applications. These DSSC parameters can be determined using a solar light simulator. The fill factor can assume values between 0 and less than 1 and is defined by the ratio of the maximum power (P,aax) of the solar cell per unit area divided by the and according to [7]... 

Parlak, E.A. The blend ration effect on the photovoltaic performances and stability of poly-(3-hexylthiophene) [6 6]-phenyl-Cgi butilic acid methylester (PCBM) and poly (3-octylthyophene) PCBM solar cells. Sol. Energy Mater. Sol. Cells 100, 174-184 (2012)... 

Solar energy conversion and photovoltaic devices encompass one of the most active applied topics of research in this area191. Thus, photoelectrochemical cells based on electrodes (Sn02, Pt) coated with tetrapyrroles have been studied for a long time191-194. Most studies were performed with phthalocyanines due to their stability and wide range of redox... 

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