20.109(F11): Mod 3 Day 4 Solar cell assembly: Difference between revisions

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The TiO<sub>2</sub> mineralized SWNT:phage complexes that you left last time were dried in a vacuum oven at room temperature.  The dried substance was then ground, using a mortar and pestle, into a powder on the micrometer scale.  To this ground material, a paste of pure TiO<sub>2</sub>, ethyl cellulose (for viscosity) and terpineol (an organic solvent) was added.  To the right can be seen the image of the paste before the SWNT:Titania powder was added (left) and after (right).
The TiO<sub>2</sub> mineralized SWNT:phage complexes that you left last time were dried in a vacuum oven at room temperature.  The dried substance was then ground, using a mortar and pestle, into a powder on the micrometer scale.  To this ground material, a paste of pure TiO<sub>2</sub>, ethyl cellulose (for viscosity) and terpineol (an organic solvent) was added.  To the right can be seen the image of the paste before the SWNT:Titania powder was added (left) and after (right).


The base of the anode has also been prepared.  It consists of a piece of glass coated on one side with 2mm of Florine-doped Tin Oxide (FTO).  Doping is the controlled introduction of impurities into a substance for the purpose of adjusting a chemical property of interest.  In this case, the Tin Oxide has been doped with Florine for the purpose of increasing its conductance.  After several cleaning steps, this base was incubated in a solution of TiCl<sub>4</sub> which results in it being coated with TiO<sub>2</sub>; this step is necessary for high efficiency performance of the device.
The base of the anode has also been prepared.  It consists of a piece of glass coated on one side with 2mm of Florine-doped Tin Oxide (FTO).  Doping is the controlled introduction of impurities into a substance for the purpose of adjusting a chemical property of interest.  In this case, the Tin Oxide has been doped with Florine for the purpose of increasing its conductance.  After several cleaning steps, this base was incubated in a solution of TiCl<sub>4</sub>, a step designed to coat it with TiO<sub>2</sub>; this step is necessary for high efficiency performance of the device.


===Paste Coating===
===Part 1: ===
#Use a resistance meter to determine which side of a prepared glass anode base contains the layer of TiO<sub>2</sub> coated FTO.  The coated side of interest should have a measurable level of resistance while the pure glass side should not.
#With the coated side up, align your glass anode base onto a gridded template containing a 4mm x 4mm square so that the square appears in the center of the base.

Revision as of 16:27, 18 November 2011


20.109(F11): Laboratory Fundamentals of Biological Engineering

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Solar Cell Assembly

Introduction

The principle of our dye-sensitized solar cells is that light absorption by a dye will provide the energy necessary to transfer its electrons to a mixture of Titania and Titania coated single walled carbon nano-tube(SWNT):phage complexes, which will act as a shuttle to deliver the electrons to an external circuit for extraction of "useful" energy. To complete the cell an Iodide redox mediator is used to recycle electrons back to the dye from a counter-electrode. During the first two lab sessions of this third module, you worked to coat genetically-modified M13 phage with SWNTs and to mineralize TiO2 upon them. (These steps are summarized visually in the top of the figure to the right) For today's session, you will use these complexes to construct the anode of the dye-sensitized solar cell. (The anode can be seen in the bottom left of the image to the right)


Protocols

While You Were Out

The TiO2 mineralized SWNT:phage complexes that you left last time were dried in a vacuum oven at room temperature. The dried substance was then ground, using a mortar and pestle, into a powder on the micrometer scale. To this ground material, a paste of pure TiO2, ethyl cellulose (for viscosity) and terpineol (an organic solvent) was added. To the right can be seen the image of the paste before the SWNT:Titania powder was added (left) and after (right).

The base of the anode has also been prepared. It consists of a piece of glass coated on one side with 2mm of Florine-doped Tin Oxide (FTO). Doping is the controlled introduction of impurities into a substance for the purpose of adjusting a chemical property of interest. In this case, the Tin Oxide has been doped with Florine for the purpose of increasing its conductance. After several cleaning steps, this base was incubated in a solution of TiCl4, a step designed to coat it with TiO2; this step is necessary for high efficiency performance of the device.

Part 1:

  1. Use a resistance meter to determine which side of a prepared glass anode base contains the layer of TiO2 coated FTO. The coated side of interest should have a measurable level of resistance while the pure glass side should not.
  2. With the coated side up, align your glass anode base onto a gridded template containing a 4mm x 4mm square so that the square appears in the center of the base.