Sahrul Saehana

Enhancement Performance of Dye-Sensitized Solar Cells from Black Rice as Dye and Black Ink as Counter Electrode with Inserting Copper on the Space between TiO2 Particle’s by Using Electroplating Method

In this study, we report well performance of Dye Sensitized Solar Cell (DSSC) coated with copper (Cu) by using the electroplating method. The Cu nanoparticle was impregnated into the pore of the titanium dioxide (TiO2) thin film. Particle contact between Cu and TiO2 plays important role to reduce the recombination effect of the electron and also lead to increase the electron transport in DSSC cell. Here, we used natural dye extracted from black rice and carbon from black ink as counter electrode. It is found that efficiency of DSSC coated with Cu nanoparticle is higher than pure DSSC which is obtained from I-V characterization. It shows that efficiency of DSSC is about 0.019% without coating Cu and enhanced about 0.105% after coating Cu. The analysis of internal resistance of DSSC was measured from Electrochemical Impedance Spectroscopy (EIS) characterization.

A new architecture for solar cells involving a metal bridge deposited between active TiO2 particles

The efficiency of titanium dioxide (TiO2)-based film solar cells fabricated by combined spray and electroplating methods was improved by forming metal bridges in the pores between TiO2 nanoparticles. The interfaces between TiO2 nanoparticles and metal bridges formed Schottky contacts, which minimized recombination of electron-hole pairs and increased electron transfer. A maximum efficiency of 4.38% was achieved for cells plated at 50 mA and 55 °C. This efficiency is higher than that reported for solar cells with a similar structure [Saehana et al., AIP Conf. Proc. 1284, 154 (2010); 1415, 163 (2011); IJBAS/IJENS 11, 15 (2011)]. We also identified that both current and temperature influence the morphology of the metal bridges and efficiency of the solar cell.

Electrochemical impedance spectroscopy study of TiO2 based solar cells

We herein report an electrochemical impedance spectroscopy study on TiO2 based solar cells in which a copper bridge was found to significantly reduce the resistance of the TiO2 solar cells. The effects of different ions in the polymer electrolyte on the resistance of the solar cells were also observed. In addition, the use of a natural polymer from the resin of Coromendelica saccharata sturt improved the performance of the solar cells, significantly increasing their efficiency and fill factor to 5.015% and 0.90, respectively.

Dye-Sensitized Solar Cells (DSSC) from Black Rice and its Performance Improvement by Depositing Interconnected Copper (Copper Bridge) into the Space between TiO2 Nanoparticles

Dye-sensitized solar cell (DSSC) which employed natural dye from black rice has been successfully fabricated and improved its performance by depositing interconnected copper (copper bridge) on the space between TiO2. The copper bridge has significant role in minimizing recombination of electron-hole which occurred in TiO2 surface by trapping electron and facilitating to anode. The presence of interconnected copper nanoparticle in the space between TiO2 nanoparticle was confirmed by Scanning Electron Microscopy (SEM) and X-Ray Diffractometer (XRD). The current-voltage (I-V) characterization of DSSC solar cells by using Keithley 617 was also performed to investigate performance of solar cells under sun illumination in varying intensities. It is found that performance of copper coated DSSC solar cells (efficiency 0.35% and fill factor 0.35) is higher than DSSC without copper coating (efficiency 0.17% and fill factor 0.35). This result is consistent with impedance spectroscopy analyzing where the internal resistance of copper coated DSSC solar cells is lower than DSSC without coated. It is concluded that performance of DSSC increasing with decreasing of internal resistance. Our finding is higher than other researcher reports in Ref. [13] and [14] with similar structure and kind of natural dye. In addition, this paper also reports the use of polymer electrolyte which employing polyvinyl acetate (PVA) containing lithium ion to maintain long-term stability of device.

Performance Improvement of TiO 2 Based Solar Cells by Coating Cu Nanoparticles into the Space between TiO 2

TiO 2 thin films with its pore coated by copper (Cu) nanoparticles have been developed in order to improve the TiO 2 based solar cells performance. Contact between Cu nanoparticles and TiO 2 play role in minimizing the recombination of electron‐hole pairs and increasing electron transfer in TiO 2 based solar cells. The Cu coating on the space between TiO 2 has been performed by electroplating methods. It is found that the solar cells performance of Cu coated TiO 2 films become higher than of the pure TiO 2 film. The presence of Cu nanoparticles on TiO 2 films were confirmed from Scanning Electron Microscopy (SEM). In this study, a maximum conversion efficiency of 3.73% was achieved.

Nanocomposite Solar Cells from ''Dirty''TiO{sub 2} Nanoparticles

TiO2 solar cells were fabricated consisting TiO2 layer, TiO2 nanocomposite layers, electrolyte polymer and counter electrode layer. It was found that TiO2 nanocomposite layer that contains metal (Zn) contact could be conductive and make better charge transfer than pure TiO2. Conversion efficiency 1.0% was achieved using TiO2 nanocomposite. It indicates that using of TiO2 nanocomposite is an effective technique for improvement of conversion efficiency.

Introducing Organization Parameter for Self‐Organized Nanoparticles

We introduced a parameter to distinguish how well (the quality) of organization of nanoparticles in self‐organized samples. This parameter measures how far the deviation of real particle positions in the sample with respect to positions of particles forming a perfect lattice of the corresponding packing structure. The perfect lattice was developed by taking the lattice site as the average distance between contacting particles in the sample.