Instrucción

Making Solar Cells1 from Household Materials (mostly :)
Equipment and Materials List Safety Glasses (20+ pairs for students and instructors) Nitrile Gloves (Supreno, 15 pairs of small or medium for students, 5+ pairs of medium or large for instructors and others) Ten 1” glass squares with conductive coatings (indium tin oxide, ITO) on one side Degussa P25 titanium dioxide (TiO2) (at least 12 g)Clear, colorless dishwashing liquid Distilled white household vinegar (5% acetic acid, ~1 M) Tweezers (At least 6 pairs) Small metal spatulas (At least 6) Scotch “Magic” tape (at least 3 small dispensers) Glass stirring rods (at least 6) Boxes of small Kim-Wipes (at least 3) Paper towels (lots) Cotton swabs (one pack of 50-100) Eyedroppers (at least 6) 10 mL graduated cylinder 20 mL graduatedcylinder Ethanol wash bottles (at least 3) Blender Deionized water wash bottles (at least 3) Oven capable of 450 °C Tongs for oven Three alumina sample boats for oven Fire brick where all three sample boats can cool Small glass petri dishes (at least 10) Graphite pencils (at least 5) Blackberries (at least 2 packs) Thin coffee filters (at least 5) Two filter setups (each consisting of a large glassfunnel, a small glass funnel, a rubber stopper for the latter, and a lab stand) 20 mL glass vials (at least 3) Smaller glass vials (if available) Binder clips (at least 10) Iodide electrolyte solution in squeeze bottles (at least 5) Five digital multimeters with clean, new alligator clips for leads Large porcelain mortar and pestle Scale and weighing paper or weighing cup WEAR GLOVES AND SAFETYGLASSES AT ALL TIMES, UNLESS SPECIFICALLY TOLD OTHERWISE BY AN INSTRUCTOR OR INSTRUCTED ON THESE PAGES

Specifically, you are making what is called a Graetzel Cell, named after Dr. M. Graetzel, its inventor. Information, solar cell kits, and many good links explaining the technology further can be found at http://www.solideas.com/solrcell/cellkit.html
Support for Cornell Center for Materials Researchis provided through NSF Grant DMR-0079992 Copyright 2003 CCMR Educational Programs. All rights reserved.

1

1

PUT GLOVES AND GLASSES BACK ON BEFORE DOING ANYTHING Preparing the TiO2 Suspension – All Groups Cooperate Materials Used: Degussa P25 titanium dioxide (TiO2) Scale Weigh paper or weighing dish Metal spatula Large porcelain mortar and pestle 10 mL graduated cylinder 20 mL graduatedcylinder Small glass vial (20 mL, smaller if available) Vinegar Deionized water wash bottle Paper towels (not specifically mentioned, but chances are you’ll need them) 1. Measure out 12 g of Degussa P25 titanium dioxide on the scale using weigh paper or a weighing dish, and put into a mortar and pestle. 2. Measure out 18 mL of vinegar in the 20 mL graduated cylinder. 3. Measure out 2 mL of deionizedwater in the 10 mL graduated cylinder. 4. Transfer the water to a small glass vial, and add two drops of clear, colorless dishwashing detergent to the vial. Stir together carefully, so as to avoid producing foam or bubbles. 5. Add about 30 drops of vinegar to the titanium dioxide in the mortar and pestle. 6. Mix thoroughly until the mixture is uniform and free of lumps. 7. Repeat steps 5 and 6 untilall 18 mL of the vinegar is used. 8. Add the previously prepared mixture of detergent and water to the paste, and very gently stir it, being careful not to produce bubbles or foam. 9. Let the suspension sit for 15 minutes.

Support for Cornell Center for Materials Research is provided through NSF Grant DMR-0079992 Copyright 2003 CCMR Educational Programs. All rights reserved.

2

Preparing theBlackberry Juice – All Groups Cooperate Materials Used: One container of fresh blackberries (containing at least 10-12 berries) Blender 10 mL graduated cylinder 20 mL graduated cylinder Two filter setups (each consisting of a large glass funnel, a small glass funnel, a rubber stopper for the latter, and a lab stand) Two coffee filters Two small glass vials (20 mL) Deionized water wash bottle Paper...