Development of Elevation Machine for Thin Film Production in Self Assembling, Suitable for Die Sensitized Solar Cell

Abstract

Solar Cell is used to convert radiation energy to electrical energy. Still they are in very primitive stage and a lot of research is needed to be done to improve efficiency. Although the efficiency and durability of organic solar cell (OSC) is to be greatly improved, the potential in that area has increased due to low cost, flexibility and light weight. Further, Dye Sensitized Solar Cell (DSSC) is popular in research studies due to the cost factor in the manufacturing process and there are lots of ongoing researches in this scenario in the world including Sri Lanka. Further, DSSCs are referred to as thin film solar cells and it is important to emphasize the thickness of the depletion layer of a cell is prominent in improving its efficiency. The optimum level of the thickness of depletion layer of solar cell is found as 20nm for better operation. There are different techniques which can be used for thin film production such as the doctor blade method, photolithography or screen print method, spin coating method, and Ionically self-assembled method. The self- assembling process has more potential as it can deposit thin film in the form of monolayer with high morphology without using complex and expensive equipment. However, the constraint is how to reduce vibration and it is required to find a proper mechanism to immerse sample of ITO glass and removing. That cannot be done directly by hand and the current practice is to immerse sample using an elevator lab jack available in the laboratory. This method is not convenient because the vibration may arise due to elevation and as a result, morphology will be reduced. In this research, the main objective is to develop a vibration free elevation method which is suitable for the film production of self-assembling process. It is difficult to use a motor controlled system because the rnonolayer may crack or break due to the vibrations of motor armature. Therefore , in this research a hydraulic elevation system is introduced as a novel technique so that it can have a vibration free system. The required speed is 8.33 x 10-5 ms-1 and the proposed system can easily vary its speed between 2. 78 x 10-6 ms-1 and 1.67 x 10-4 ms-1, which provides ideal conditions suitable for ISAM technique. UV-Visible Absorption Spectroscopy was used to observe the growing of the monolayer because it gives an indication about absorption with the thickness of formed layer according to Beer-Lambert law.