Onto Light-er things

My research project involved trying to solve some aggregation problems that occur in the active layer of a new, experimental type of solar cell (hybrid polymer-nanoparticle SC) by incorporating a species of algae, called a diatom, into the structure. My project comes in four distinct phases: isolating and cleaning the diatoms, chemically converting their material into something more suitable for photovoltaics, assembling a solar cell with the diatoms mixed into the active layer, and testing the solar cell for efficiency. For the past year or so I have been working on converting their chemical structure. The goal was to coat them in TiO2 using an established procedure by another researcher. When we were analyzing the diatoms on the SEM though, we only found minimal signs of Titanium. At first we thought we must be doing something incorrect with the deposition, and so we repeated several times. Same result. Finally, the new TOF-SIMS came online, allowing us to do more surface analysis, and our Titanium counts in that machine sky-rocketed! All of the Titanium was deposited along the surface of the diatoms (which is actually ideal) which is why we couldn’t see it in the SEM! Finally having completed this stage of the process, we have begun moving into the next: assembling the Solar cell. After more literature research and several drafts of procedures, we settled on an assembly process we think will work well. The materials have been ordered, the spin-coater has been calibrated, everything is set up to begin, we are now just waiting for the chemicals we ordered to arrive in the mail (a frustrating delay, but there’s not much we can do to speed up the mail!)


  1. jngranger says:

    Hey Megan! So, actually I dropped by your lab and talked to your professor about the problems I was having with our TiO2, because it turns out you guys are trying to do almost the exact same procedure with it! She had some useful insights. To answer your question, we are using TiO2 because there is a reliable procedure that exists to coat diatoms in TiO2 nanoparticles, so our choice in semiconductor is rather limited to the existing research that has already perfected this technique. Since I’m not a chemist, I lack the expertise needed to develop a new procedure using a different material. So alas, we are trapped into using this material for now. Thanks for the question!

  2. mescreen says:

    This sounds like exciting research! My research in the chemistry department has also included TiO2. Why does your research use this specific semi conductor? Have you tried to use any other semiconductors as controls or to improve your results?