Pang Nganthavee, Week 5-7, The Fourth and Final Run ft. SEM & Sequential CaRI

Just as the fifth week at the Lee Lab was about to begin, I received an email from my P.I. asking for me to prepare a report of some sort that summarized my work in the lab so far. As I already have a presentation file compiling all of my data as well as the parameters of my experiments on hand, I decided to use that as the starting point for my report. After organizing the data in chronological order of what I did during the past four weeks, I also added parameters of the experiments I conducted as well as observations that I noticed while performing the procedures. After I finished up organizing my data, I proceeded to share it with Jyo Lyn, my grad student, as I asked her to look over it before I shared it with my P.I. After she looked over my work, since the presentation file I shared with her did total up to 93 slides, she said that it was way too long. Therefore, she suggested another way for me to organize the data, by grouping them in a different way instead. After I re-organized my data according to her suggestions, the final slide count totaled up to 47. Even then, it was still very long, however, it was basically half the number of slides that I originally had, so I was making some form of progress, and was what I sent to my P.I. to look at before I met with him to look over the data that coming Friday.

During the meeting we had on Friday, some questions were raised regarding a few parts of the data. What he questioned was the data of the composite films that have gone through annealing. It has been proven many times in the results of research done previously that the structure of silica does not change even after the polymer has infiltrated through via capillary rise infiltration. Due to how the structure should remain the same, the thickness of the final composite layer of the film with both polymer and nanoparticles should remain the same as when the top layer consisted of only silica.

The Problematic Change in Thickness Slide ^^"

What Jyo Lyn and Dr. Lee thought what caused this issue is due to how the film’s roughness as a result of the aggregated nanoparticles might have caused the ellipsometer to not be able to detect the layers of thickness properly. Therefore, what they suggested for me to do was to remeasure my annealed films from my most recent run with the following changes:

1. Turn off the roughness
2. Fix the C value to be at 0 - a measurement used as a part of what is needed to calculate the refractive index of the film

By doing so, it increases the chances that the values given by the ellipsometer will make more sense and essentially more “accurate” as there are less variables for the ellipsometer to work with, and therefore decrease the chance of something that may have been measured/adjusted wrong.

Therefore, for week 6 at my lab, basically consisted of me re-measuring all my films from my third run as well as going through a fourth run of synthesizing low filler fraction nanocomposites. After finishing up the remeasurements and running this experiment one last time, I was able to make sure that all the trends that I have noticed in my analysis of various runs are coherent with each other.

The beginning of week 7 consisted of me analyzing the data and organizing it into a report for Dr. Lee and Jyo Lyn to easily look and go over it. As I had done this once before, I knew the basic format of how they wanted my data to be organized so this second time, the process of doing that was much more smooth-sailing. Towards the end of week 7, Dr. Lee gave me a new project for me try. What he wanted me to do was a process called “Sequential CaRI”. It is a process that is extremely similar to what I was already doing. However, the difference was that I wouldn’t have to age the silica nanoparticles, and instead of annealing the bilayer films once, I would have to anneal it several times after many spin-coating sessions of silica. At that time, it was only a theory he thought might work, but no one has yet to try. Therefore, since I completed my original project early, he said for me to try this. If it worked, great. If not, that was fine as well. After finishing all the planning required, I began to prep my silica and polystyrene solutions on Thursday morning, and then proceeded to conduct the experiment over the rest of Thursday and Friday morning.

i

Some films I made from Sequential CaRI

Friday afternoon was when Jyo Lyn took me over to the Singh Nanotechnology Center to image some of my films via SEM (Scanning Electron Microscope). By shooting electrons at the films, the machine was able to come up with an image. With this, I was able to confirm that the porosity of my silica nanoparticle packings were actually increasing and that the polystyrene was actually infiltrating into the interstices of the silica nanoparticle packing.

Top-down view of a t=124h silica-coated film 

--------------------------------------------------------------------------------------------------------------------------------

Outside the lab, on the 4th of July, as well as being Independence Day, that day was also actually my dad’s birthday! As Jyo Lyn told me that no one would be coming to the lab on that day to celebrate the holiday, I could also take the day off as well. Therefore, on Monday night, I asked my dad what kind of food he wanted to eat for lunch the next day in order to check online whether or not the restaurant we could possibly go to on Tuesday would be open or not, and then Tuesday for lunch, we headed out to Ochatto to grab some Japanese food and bubble tea! Steph and I had come to this restaurant once to “survey” their food, and we both thought that it was really good. Since my dad hasn’t gone out to eat at this restaurant yet, I thought it was the perfect opportunity to take him there. We both ate steak teriyaki bentos - they were really delicious!

The following weekend was when I went out to do some more exploring. Steph went home for the weekend so I was only able to go to see the Eastern State Penitentiary and the Penn Museum with my dad. We both really enjoyed touring and looking around both of the places.

My dad standing in front of a sphinx at the Penn Museum!

After week 6 at my lab came to a completion, it was finally time for me to take TOEFL. After a gruelling and long four hours in the testing room at Temple University, I was finally done! To celebrate the completion of TOEFL, my dad and I decided to stop by Chinatown for some Korean BBQ. I managed to find one that was all-you-can-eat called Nine Ting. After I checked the price and saw it was fairly reasonable, we hopped on the subway and headed there. After we ate our full at Nine Ting, we thought that a meal is never complete until there is dessert. We made our way over to Ice Land, which was only a 3-minute walk away, and filled our already-full stomachs with even more food! I hadn’t felt that full in a very long time!

Roll Ice Cream!!!

The weekend after week 7 at the Lee Lab came to end, Steph, Jerry and I met up to go out to eat at Nine Ting. At first, we were planning to go try another Korean BBQ place, but since we all thought that Nine Ting was probably the best one out there from what we could tell, we just went there. I didn’t mind going twice since I really enjoyed their food the first time around!

KBBQ at Nine Ting!

Looking ahead to the last week that I will spend at the Lee Lab, I will probably be continuing to organize my data into a report that I will be present to my P.I. for the last time. I hope that all goes well!