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A new method has been developed for surface treatment of TiO2 photoanodes with LiI/NaI to enhance the photocurrent and, subsequently, the performance efficiency of the fabricated dye-sensitized solar cells (DSSCs). Three different concentrations (0.1, 0.25, and 0.5 mmol%) of LiI and NaI solutions were used to investigate the effect of this surface treatment on the device performance of DSSCs. A positive shift in the energy level of TiO2 has been experienced by surface treated devices, which is predominantly supported by the decrease in VOC. Furthermore, the introduction of LiI/NaI onto the TiO2 surface resulted in a reduction in the crystallite size, indicating an increase in the surface area which helps in more dye adsorption leading to higher JSC values of the devices. Besides, modification of the conduction band energy level, it also allows a fast electron injection process by shifting the density of states. Thus, this approach offers a simple but efficient route to enhance the photocurrent and efficiency of DSSCs.

Amorphous silicon-based thin-film minimodules have been irradiated with 68MeV protons up to a dose of 1×1012 protons/cm2. During the irradiation, the solar cell current under short circuit conditions, due to the photogeneration of charge carriers by the low-intensity room light and the radiation-induced generation of charge carriers, has been measured. Whereas the degradation of the photo-induced current can be continuously monitored during the experiment, the smaller radiation-induced current is only visible in current discontinuities at the beginning and the end of the radiation period. In our experiment, we measured a very similar decrease in the photo- and the radiation-induced current, both due to the proton irradiation. Therefore, we can infer that the degradation of the solar cells’ photoelectrical properties is mainly due to the degradation of the amorphous silicon active material and only to a smaller content to the glass substrate’s optical transmission properties. Directly after irradiation, we observed a continuous recovery of the photo-induced current, due to the room-temperature annealing of the electronic defects created in the amorphous silicon absorber layer.

An ultra-low cost temperature sensor has been developed that uses as active sensing material an epoxy layer, mixed with a small concentration of multi-walled carbon nanotubes. A stable NTC characteristics has been measured during temperature cycling. Under Joule heating conditions, a linear current-temperature characteristics has been obtained.