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CHEM 146_Experiment #2 Making a Solar Cell with TiO 2 Nanoparticles. Yat Li Department of Chemistry & Biochemistry University of California, Santa Cruz. Objective. In this laboratory experiment, you will learn:. The basic principle of dye sensitized solar cells
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CHEM 146_Experiment #2 Making a Solar Cell with TiO2 Nanoparticles Yat Li Department of Chemistry & Biochemistry University of California, Santa Cruz
Objective In this laboratory experiment, you will learn: The basic principle of dye sensitized solar cells A easy way to make dye sensitized solar cell using simple device fabrication techniques Electrical measurements for solar cells
Energy and environment Grand Challenges: • Limited amount of oil • Emission of CO2 Non-carbon based energy: • Nuclear energy • Renewable energy (clean & constantly replenished) • Solar energy • Biomass fuel, such as ethanol • Wind, water, geothermal heat, biological process
Renewable and clean energy Solar Energy: 125,000 TW of solar energy striking the surface of earth Global energy consumption: 13.5 TW in 2001 (85% from fossil fuels); ~ 30 TW in 2050 0.16% coverage with 10% efficiency solar cells can generate 20 TW of power Challenges for solar electricity: EFFICIENCY & COST! Solar electricity residential price is around 40 – 80 cents per kilowatt hour depending on the climate, which is at least 4 times higher than the charge of electricity supplied by major gas utilities.
Dye sensitized solar cells (Grätzel Cell) “ Nanocristalline Solar Cell Kit ” ICE University of Wisconsin-Madison USA http://esamultimedia.esa.int/images/science_on_stage/IT_Giambelluca_Gratzel_cell_cella.swf http://esamultimedia.esa.int/images/science_on_stage/IT_Giambelluca_Gratzel_cell_energia.swf
Dye sensitized solar cells (Grätzel Cell) “ Nanocristalline Solar Cell Kit ” ICE University of Wisconsin-Madison USA http://esamultimedia.esa.int/images/science_on_stage/IT_Giambelluca_Gratzel_cell_cella.swf http://esamultimedia.esa.int/images/science_on_stage/IT_Giambelluca_Gratzel_cell_energia.swf
Nanowire dye sensitized solar cells Law et al. “Nanowire dye-sensitized solar cells”. Nature Materials Mater. 4, 455-459 (2005) ZnO nanowire arrays for dye sensitized solar cells: A better vectorial charge transportation is expected in nanowire vs. nanoparticles!
Preparation of TiO2 dye sensitized solar cells 1. Making TiO2 film 1 2 3 4 5
Preparation of TiO2 dye sensitized solar cells 2. Baking and sensitizing the TiO2 film with dye molecules (from blackberry juice)
Preparation of TiO2 dye sensitized solar cells 3. Making graphite counter electrode
Preparation of TiO2 dye sensitized solar cells 4. Making a dye sensitized solar cell
Photoresponse measurements Disconnected Connected Connect the dye sensitized cell to a multimeter and measure the photovoltage and photocurrent: • dark; • ambient room lighting; • light bulbs 50W and 100W • blue, green and red light • as a function of distance from 100W light source to substrate