Cut a piece of nickel mesh to cover the flange of the syringe cylinder completely
Place an aluminum plate on a heating plate. Place the baking paper on the Al plate and the nickel net on the paper.
Heat the plate to a temperature that will melt the plastic but not burn it.
4. Place the flange of the syringe on the nickel net on the heating plate. Press down firmly so that the nickel net is melted onto the flange. Make sure that the net is sealed tight to the whole of the flange surface, but take care not to melt so much plastic that the cylinder hold itself is covered with molten plastic.
Remove the syringe and net form the eating plate and allow to cool.
At one of the sides of the flange drill a hole through the flange using the electric drill. Place a piece of wood beneath to prevent drilling into the lab bench. (see picture) Push the machine screw through the hole and fasten using a washer and nut. (see picture)
Mount a piece of insulated copper wire around the machine screw by twisting an end into a loop with a flat bit and fastening it with the nut. Tighten it so that good electrical contact is established between the wire and the nickel net. Use tape to attach the wire to the syringe cylinder.
Cut off excess nickel net around the flange.
Clean the nickel net by immersing the electrode in 4M nitric acid for at least five minutes. Also clean the extra piece of nickel net in this manner. This much be carried out in the fume hood since poisonous flumes may evolve. Rinse thoroughly with water.
Place the nickel net of the electrode in a solution of palladium chloride for 30 minutes and then gently rinse with water. Be sure to put the extra piece of nickel net in the palladium chloride solution as well. The electrode is now ready. You should have something that resembles the picture.
Figure 1: Drilling holes in flange.
Figure 2: Wire connection assembly.
Figure 3: Final assembled cell
Building the cell
First cut top off of one of the syringes. This will be the electrode you introduce the liquid/solid fuel.
Place your two electrodes into a 600mL beaker containing 1M NaOH solution. The nickel meshing should be completely submerged in solution.
Fill a balloon with oxygen gas (from gas cylinder) and connect using rubber hosing to the syringe that was not cut. The oxygen may bubble slowly through the syringe.
Roll up the extra piece of nickel mesh and place into the cut syringe.
Add ~20mg of NaBH4 to the syringe with the extra piece of nickel mesh. If time permits you may test other fuels later.
Figure 4: Functional cell layout.
Testing the cell
Measure the voltage generated by your cell by taking a digital multimeter and setting it to DC voltage. Connect one probe to each wire of the cell. The reading may continue to grow for a while and then stabilize. Record this stable voltage. It should read between 0.8V-1V.
Measure the current your cell sources by keeping the probes connected and switching to current mode. This reading should be between 30mA-50mA.
