Study of photoconductivity of nanocrystalline titanium dioxide used in dye sensitized solar cell

Abstract

In this work the nanocrystalline TiO 2 -dye sensitized photovoltaic cells are constructed and studied. This type of photovoltaic cell consists of a thin film of nanocrystalline titanium dioxide (TiO 2 ) particles with natural black berries juice as dye molecules on their surface. When the dye molecules are excited by a light source, electrons are transferred from the dye to the TiO 2 and produce a photovoltaic effect. The circuit of the photovoltaic cell is completed by applying an electrolyte solution. The efficiency of such a photovoltaic cell depends on the state of the TiO 2 , the type of dye, and the electrolyte solution used. The purpose of this study is to develop solar cells with increasingly higher voltage and current outputs and to have our results as predictable and reproducible as possible. Research is still in the stages of testing various dyes, and electrolyte solution in order to obtain better results and more efficient solar cells. I. INTRODUCTIONRecently much attention has been given to the dye sensitized solar cell by the scientific society around the world working in this area because they show high efficiency, easy to fabricate and low cost alternative to conventional inorganic photovoltaic cell [1-6] Dye-sensitized solar cells (DSSCs) are a relatively low cost solar cell technology that has achieved overall light-to electricity conversion efficiencies of over 10.6% [1,7]. Today in the modernization world, humans began consuming nonrenewable energy resources at a devastating rate. In order to reduce non-renewable energy consumption, reduce atmospheric pollution, and avoid global climate changes in the near future, scientist around the world are looking to tap into renewable energy resources such as solar energy. One promising technology that directly harnesses the energy of the sun is based on photovoltaic.To secure a future energy source for technologically advanced societies around the world as well as help to reduce the negative environmental impacts of human activities, cleaner renewable sources of energy need to be utilized. The ultimate energy source available to us is the sun; if all of the radiant energy reaching the surface of the earth could be effectively harnessed, the world's energy problems would be solved.The Nanocrystalline semiconductor comprised of wide band-gap oxides are known to show extraordinary optical and electronic properties and are very suitable for use in photovoltaics [8][9][10][11], photocatalysis [12], electrochromic [13][14][15], and