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On May 27, 2011, Fievel of andthenbam.com and I measured a potential of 0.3 V across a dye-solar cell. We had been working on the project, which involves dyeing a solar cell with blackberries, for the past couple of months.

I initially found out about the intriguing concept behind dye solar cells through a Fast Company article.

In January 2011, I happened upon Solaronix's Dye-Solar Cell Projects for Real from the Wikipedia page. Around this time, I was excited that my friend Fievel was also interested in the project.

The raw materials in a traditional photovoltaic cell are silicon, boron and arsenic. To make a PV cell, pure monocrystalline silicon crystals are first grown at temperatures up to 2000 degrees Celcius in a kiln for a couple of days.

In comparison, a dye-solar cell can be made of a number of chemicals. In contrast to the PV industry, these chemicals are not necessarily also in demand by the much larger semiconductor industry. Additionally, the anode and cathode plates in a dye solar cell must be fired at a mere 450 degrees C for only 20 minutes.

The anode in the dye-solar cell we made is a titanium paste that is not sensitive to light. In order to free electrons, the anode must be dyed with berries or beets. It is this use of organic compounds that makes the dye-solar cells unique. An additional advantage is that dye solar cells perform in low, reflected and obstructed light conditions (though their peak efficiency is lower than PV).

Fievel coordinated the materials purchasing. We bought most of the materials from Solaronix, the Swiss company that published the DIY manual.

MaterialSourceBase PricePrice ($)Amount UsedPrice Per Cell ($)
Ti Nanoxide PasteSolaronix250 CHF2761/382.8
Platisol Cathode PasteSolaronix45 CHF501/315
Iodolyte ElectrolyteSolaronix92 CHF1011/330.3
Meltonix Film (3)Solaronix96 CHF1131/129.40
TCO Glass Plates (10)Solaronix90 CHF1072/1021.4
Shipping from SwitzerlandSolaronix----
Magic TapeRite Aid-2.50-2.50
Deionized WaterRite Aid-1.60-1.60
CaulkingHome Depot-3.98-3.98
Alcohol WipesBio-Pure-20.005/402.50
BlackberriesFred Myers-3.0013.00
Total172.48

Notes:
1. Estimate that about 1/3 of both the Titania paste and Platisol cathode paste were used for one cell.
2. Estimate that 1/3 of the iodolyte electrolyte was used for one cell.
3. Estimate that 1/4 of one sheet of film was used for one cell.
4. Solaranix kindly shipped the materials for free. Typically, the shipping cost is $100, with an additional$30 for customs inspection.

Things to improve next time:
1. Cover the glass plates when taking them outside before firing. We took great measures to be careful with the glass plates while drilling, but forgot that we live in Portland, and that it drizzles constantly!
2. The iron doesn't do a good enough of a job in sealing the two glass plates. A hot press is needed.
3. It is important to deposit a THIN layer of titanium onto the glass plate. If the titanium paste is too thick in any spot, it will not form to the glass. This layer should be uniform and without little bubbles.
5. Titania paste is the MOST expensive component!!! It would be beneficial to source the paste from a local chemical company and buy in bulk.
6. After some experimentation, Fievel concluded that the caulking is superfluous. He used tin foil to plug the holes in the glass plate.

Fievel and I presented the dye-solar cell at the rally in support of solar incentives at the State Capitol in Salem on June 1, 2011. One of the attendees later offered the chance to have a booth at the Oregon Berry Festival on July 22-23.

Overall, I am very thankful to Fievel for being interested in the project. He took the initiative in ordering the supplies and helped me make sense of how the cell works. Through this project, I got to experience a sense of camraderie, as well as what small-scale manufacturing feels like.

Fievel later measured the current to be 0.0037 A. Even with this meager power (0.00185 Watts), I cannot help but to take pride in the end product.

8 Responses leave one →
1. October 7, 2011

You should be proud Roma, our cell transmits 37.4 trillion electrons per second from pure natural sunlight!

• October 8, 2011

Damn straight. I like your math!

June 25, 2012

Good work guys !!