Altstadtfeste

           This weekend there was a huge festival in downtown Saarbrucken. Ther was music and live

performances on almost every street, Regional foods stalls peddling Schwenker and Flamchuken (I am

 aware that I cannot spell and am working on it). rows of street vendors selling everything from handmade

leather bags to banzai trees, and of course copious amounts of beer.

           There were amazing musicians preforming on multiple stages throughout downtown Saarbrucken.

 One particularly memorable on involved a drum duel between a metal drummer and a bongo player
.
           On the research side of things I spent this week reviewing literature and learning how to use the

machines that I will need for my research. I got to use the SEM and got a lot of practice in spinning my own

 fibers with the electrospinner.

            Overall it was a pretty good week I wish this festival would never end.

(pictures will be added later. I have them they are just proving difficult to upload)

Staying in Saarbrücken

Starting to Spin

Welcome to the Teknikum which is our lab in Germany.  Last week, my colleagues and I received a formal tour of the facility and began some preliminary lab training.

This machine pictured behind the cabinet (see picture below) is for electrospinning.  This past week, my colleagues and I learned how to electrospin fibers which is useful for most of our projects.  In my particular research, I am spinning fibers to be used in a material for a separator in supercapacitors.  Supercapacitors store energy.  Electrical double-layer capacitors (EDLCs) are a type of supercapacitor that require a separator.  A separator provides a barrier so that the supercapacitor does not short circuit from the flow of ions; however, the separator must also demonstrate enough porosity for electrolyte to flow through.  In the past, electrospinning has contributed to very porous materials which would be perfect to incorporate into separators in supercaps.  Electrospinning is also a fairly affordable, simple process and would be beneficial to commercialize if successful.  Overall, this project aims to produce more effective, efficient separators than what is already commercially available.

At the current moment, I am going to spin three polymers into materials to see how they will act in a separator material.  On Monday, I hope to spin my first solution and see how that works as a separator material.  In addition to research and lab work, my colleagues and I attended our second lab meeting.  During this lab meeting, we all had to prepare a five slide presentation to present in front of the entire group.  Even though I have done presentations before, I was particularly nervous for this one.  In the end, I had nothing to fear because I knew the information and was able to articulate my project to the group.  For me, the New Materials for Energy group is beginning to feel like a family.



Studying in Saarbrücken
Not surprisingly, the first question people usually ask once they find out that I am American is "Why are you here?"  The simple answer is that I am conducting research at the University.  This past week I decided to stay in Saarbrücken instead of traveling to another city.  I really did enjoy Bonn, but I wanted to relax a bit in my own city since I really did not get the opportunity to do so the first week because I was either sleeping or in Starbucks for the free Wifi.

After walking around Saarbrücken, I found so many restaurants and stores.  First off, Primark is probably one of the best stores and should be brought to America soon.  Imagine four floors of the cheapest and cutest clothes available.  Unfortunately, so many people were in Primark that day that I decided to come back at another time.  Also, I found stores such as a musical instrument store that actually showed the workshop of the person who makes them (pictured below).  All of the instruments had meticulous craftsmanship.  I really wish I could purchase one of these instruments, but I highly doubt that one would fit in my carry on and that I have the budget for one. Overall, I am happy to have wandered around this city especially during the festival.

Pictured below is part of the festival that took place in Saarbrücken this weekend.  Imagine a bunch of tents selling homemade goods and delicious food places while five or six different stages are producing music all across the city.  I wish Philly had these type of festivals because literally I had so much fun this past weekend.  Today is the last day of the festival and I will be enjoying all the food.  What I do find particularly different about Germany is that there is a certain way that people feel they need to act.  People do not dance in public when music is playing which is sad because the music is catchy.

This past weekend I also found that people do not like pictures taken of their work because they are afraid that people from China will reproduce their goods at a cheaper cost.  For this reason, I have removed the pictures of all the different types of jewelry and goods for this blog.  I am not certain if this would happen, but I respect the people here enough to abide by their requests.  In general, I have found that people in Germany do not like cameras.

Hi from Crete!

Hello from Crete!

I just arrived a few hours ago to this beautiful island and am already loving it. I am living just outside the capital city of Heraklion in a really nice family-run hotel with a few other Drexel students. I haven’t had much time to explore yet as I needed a well-deserved nap, but I will definitely be posting some pictures in the upcoming weeks. However, what have I been up to the past week you may ask? My community service project in Israel officially ended on Wednesday so I had been spending the last 3 days in Tel Aviv making up on the work I missed the first couple of days. This included answering emails, setting up appointments with officials to meet with and talk to in Crete, and catching up on my readings and scholarly journals. I have been taking notes on all different articles and books and looking at background information and preliminary research. Starting on Monday, however, I will start to be focusing more on my project as I will officially be able to work in person with my mentor and with the PHD student. I am also taking an anthropology course while I am here which will begin on Monday. So as you can probably tell, I am looking forward for the new week to begin.

I will try to post more later in the week but now I am off for dinner time! 

Germany. What to say? Already the experience has been an interesting one. I could say that it is different from America but that would be akin to saying that watermelons are different from apples. What is surprising is the ways in which the two differ. One of the most amazing differences is the water. The water here is so clean! I do not mean the bottles water I mean the tap water. It has none of that vaguely disquieting taste of metal that I have come to expect form city water no it is entirely and wonderfully tasteless. Another difference in the water is seen when you consider the water ordered in restaurants. Here in Germany if you order water it is assumed you wanted mineral water. You have to specify that you want tap or still water. Personally I do not understand why this is true because their tap water is excellent as I previously noted, but there is some sort of stigma attached to it they see tap water as toilet water.

I also feel as though I am constantly whispering.  It is a lot quieter here in Saarbrücken. So what I consider a normal talking voice is really more like yelling to them. It is at once fascinating and frustrating. You quickly become very conscious of your own tone. I am not entirely sure if it is just a difference between America and Germany or just between being in a big city and something that I would call a town albeit a large town that is still nowhere as large as the city that I am used to. But I still need to do more traveling to see if this is true.

“Germany Has fought many wars with bureaucracy, and lost them all” After this last week I truly appreciate the truth of that statement.  In all honesty the last week can be split into two distinct parts. Reading and paperwork. There was sadly more of the paperwork than the reading. Well that is not true but the paperwork just felt like it would never end. In truth we spent hours reading because. We needed to get ready for the research but more on that later. The one thing that was confusing was the back and forth. We would basically get sent from one person’s office to the other with instructions on what to do when we got there, only to be sent back to the office we came from before... with the same instructions. With that said I can say that had we been in America the amount of hoops we would have to jump through to get health insurance would make the best of trained seals throw up their fins in protest So I guess it wasn’t really that bad.

Research part.

Not much to be said at this point the objective of the project is still unclear to me. I do know that I will be working with pseudo caps, short for pseudo capacitors. This form of electrochemical capacitor is closely related to the well-known EDLC (Electrochemical Double layer capacitor). They store energy by means of redox reactions instead of in a helmholtz double layer(as do EDLC's). In particular I think we are trying to implant Pani(Polyaniline) on Carbon fibers derived from PAN(PolyAcryloNitrile). It is difficult to do this for several reasons. One is because we are not sure we can stop the PAni from completely covering the pan(this would make surface area smaller which is very bad) and we are not yet sure how to sythesize the polyaniline /o a very strong carbon destroying acid which would destroy the surface we are trying to coat. There are many things to consider in this experiment so it will either work of be a complete mess i have no idea which one it will be yet. 

Ants, Bugs, and Girls That Go AHHHHH

June 25, 2013
It’s a rainy day! I’m supposed to sad because that means we can’t go out and find some more ants today but I’m not because that mean we don’t have to hike! My poor legs are killing me. So today is a map drawing, field notebook organizing, and possibly ant caste drawing for my STAR poster day. And stretching. Lots of stretching. 
This morning looked like this day would be our typical wet season day so we should have seen this coming, but we had a coffee and tea meet and greet kind of thing at some of the residences house. It started at 9:30 and we didn’t leave until 1:30. Needless to say, we spent a long time enthralled in stimulating conversations and good little snacks which were a mix between cinnamon rolls and hard bread. Everyone was very amenable and we shared tons of stories including our “The Scorpion Debacle.”
Here’s how that went:
I had asked Kaitlin for an extra mattress pad that we found in her room. Upon moving said mattress, Kaitlin exclaims that there was a little scorpion hiding behind. Kaitlin being the cute bug person that she is, is all like “Aww. Look at the cute little guy.” We all get up to go see it and ending up crowded in her doorway. Then this very odd series of events unfolds. Someone behind me starts backing up, then someone else kinda jumps around causing the other person to run into the other room. I, being the not bug person that I am, make the conclusion that the scorpion has gone into invisible mode and is now running full speed at me, stinger ready. The obviously calm and appropriate response was to do a flying leap into the air and on to a chair. My actually rather graceful flight was accompanied by the piercing screams of terror produced by Tessa, Siobhan, and myself. Meanwhile, Kaitlin and the scorpion, who was as it tuns out not in invisible attack mode, just sat there chilling. It was a very good demonstration of mass hysteria.

We did get one good hike in this morning to go check on a new colony by the house Professor Sean had found yesterday.  Unfortunately, the little buggers emigrated last night after we had checked on them. Ensue a nice little romp through the forest following the rough compass bearing that the colony had raided in the previous day. (Army ants tend to emigrate in the same direction they raided in the day before.) After trailing a tiny trickle of a column of ants, we eventually found this puny excuse of a bivouac that we assume its the new one.
(I’m just now realizing I haven’t adequately described army ants for you all. Here’s what I know: Eciton bruchellii are rather large ants (by our standards) with black bodies. The heads range in color from black of a worker , pinky of a porter, and white of a solider. These ants are carnivorous so to go get food they raid, basically they spread out from the bivouac and kill any bugs in their path, some several hundreds times their size. There they promptly rip it apart and drag it back to their bivouac which is where the porters, the heavy lifters, come in. The ants keep a direct link to the nest via columns, basically a highway of ants extending from the raiding front to the bivouac. They don’t really kill humans, to be honest I haven’t asked if anyone has been killed, but their bite and sting hurts like a not nice word I’m sure Drexel doesn’t want me to put on this blog. A cool feature of army ants: they can build bridges with their bodies over gaps. It’s no wonder they use them as nightmare bugs in Indiana Jones.)

It’s funny, I frequently lose my way while hiking (with other people thankfully) because I am so fixed on looking at the ground for ants that I forget to look up. I miss so much. I wonder if that’s how we should feel back in the states when we are so fixated on our cell phones. 

Other humorous stories:
Tessa’s piercing shrieks echo in the house as she frantically tries to unlock the decidedly stubborn bathroom door. The rest of us thinking that she was surprised post shower by another scorpion, await her escape, which she eventually manages to do. 
“Scorpion?”
“There is a giant mouse in the towels!” (I don’t get it, everything is super-sized here.) Surely enough a rodent of unusual size scampers out after her. (Not the size of the ROUSes in the movie, though they do have a less ugly more cuddly version of those here called Agoutis.) The response it illicited from most of us was “Aww” or “Hey, that’s a species you only find here.” Tessa and I acknowledge those from the safety of the kitchen chairs. 
Speaking of Tessa and me, clearly not bug people, we found a roach in our room. (We have to accept that we are not the only living things sheltered in this house but it was just one step too far with the crawling over our stuff.) Tessa wielding a bottle of sunscreen, rather than the more practical shoe right next to it, attempts to smoosh the intruder. The odd thing about cockroaches is that they have a really hard smooth rounded back. So when Tessa attempted to smoosh it, what she succeeded in doing what propelling said roach at breakneck speed right towards herself. Ensue much more screaming. I’m sure chair would have been jumped on had they been accessible. 
For the record the word for cockroach is “la cucaracah” not to be confused with “la cuchara” which means spoon. Yea... my suggestion is to not mix those up. 

June 26, 2013
So I tried to get up to go running this morning. I actually got around to setting my alarm. But when I woke up at 5, I realized I didn’t set out my stuff the night before. Fearing that I would wake Tessa, I turned of my alarm. That totally wasn’t an excuse or anything. 

June 27, 2013
Rainy day today. I’m not quite sure what that will entail yet though. 
Yesterday we tromped around the Stouckie Farm to check on the two bivouacs. Of course we had to stop at the epic view along the way.

 Our one good one is staying put for the time being which is very good for data. The other one had moved. However, when trying to climb a strangler fig, Professor O’Donnell discovered a raid column crossing the trail further up. After following the column we discovered a colony nesting in a tree ten feet up! I managed to get stung on this expedition. Not a pleasant feeling let me tell you. It stings long after the actual attack. The ants were everywhere, thank god they can’t fly. (Strangler figs by the way are these really cool tree/vine/plant things. They start out as epiphytes growing on a branch. Then they send down roots which reach the ground eventually. Once it does, it’s growth accelerates and the vines suddenly decide to not be roots anymore but trees. So the tree-like vines wrap around the host tree and quite literally strangle the tree by cutting off the water flow of the vascular tissue. The host dies and decay away leaving a mostly hollow, really charismatic tree. Very good for climbing.)

The afternoon was filled with guess what, more hiking! These trails have been named the “behind the institute” trails. (They do have a better name but for the life of us we cannot remember it.) Sadly no army ants were to be found of this particular portion of the mountain side. However, there was a stream that ran through one of the small valleys. We haven’t really seen a lot of running water since most of it is in the valleys. We can hear rivers sometimes if we are by a cliff edge but that’s about it. Anyway, the point is that this was a new thing for us. We sent a good amount of time playing around in the water and standing in water up to the top of our field boots, also known as wellies! Best investment ever made.

Afterwards, Professor treated us to ice cream at the creamy situated at the entrance to the trails. Mmmmm. Savoring out delicious and quickly melting treats, we continued on to “the magic path,” unfortunately not having to do with unicorns or fairy god mothers. However, to bug people like Professor Sean and Kaitlin, whom I am convinced was born with a stick insect in her hand, this hike offered something that is rarely ever seen. The colony here was reproducing and preparing for a split. Basically, the colony grows, splits down the middle, and the two halves march in almost polar opposite directions of each other, never to come in contact again. We walked in right in the middle of this.

After a not a long feeling day of hiking (I think my legs are getting used to it), we made a quick pit stop at La Colina Lodge where Sara and Mica are staying. We found Mica relaxing in a hammock reading with a cat purring on his lap. We sat down with him, resting our tired, but not thoroughly exhausted, legs. Tessa indulged in her fascination of birds here and asked Professor Sean to whom each call belonged to. This is how one of their conversations went:
*bird sound*
“Sean, what’s that one?”
“That is the Clay Colored Robin. You know, they say that Clay Robins sing when it’s going to rain” And then the heavens opened and it poured. It was a little creepy actually. 
Yesterday was also the first time that Tessa and I went off on our own to bivouac check. It was only the two here, on the Rockwell Farm, but we had a hard enough time with that. It was getting dark which meant that it was already dark under the canopy. So trying to find bivouacs that only one of us had every seen before was interesting. Thankfully both had stayed put so there was no need to go further traipsing around the forest in search. 

It being a rain day today, we are doing a lot of the indoor stuff like thermotolerances of individuals. This basically means we are heating individual ants until they die and find out what temperature their death occurs at. (It’s a bit sick when you think about it.) This way we can compare individuals to the bivouacs data. (Or so I’m told.) The test requires that we go get live specimens so Kaitlin and I went out to the bivouac closest to go retrieve some. After getting lost a couple of times despite the flagging tape, and nearly stepping on a pair of mating snakes, we eventually found the bivouac which was HUGE! It had grown to the point that it had swallowed the control iButton which was 15 cm away from the bivouac when we first put in the iButtons.

I guess this would be a good time to also mention that there is a butterfly migration going through Monteverde. I’ve never seen so may butterflies in my life.

Where Jeans Are Fancy

June 23, 2013
This is where trails are hidden and jeans are fancy. 
Yesterday we went out to the last bivouac we found hoping to test our iButtons (the temperature probe) and cameras. Unfortunately, they had moved into the base of a rotting tree, much like the other two we found. It’s hard to deploy the iButtons when there’s a nice large tree in the way. Thankfully, the first bivouac we found is dropping a lot of pupa casings which means that they are about to emigrate. (Army ants go through stages of emigration and ~ 2 week statary periods.) Hopefully they will move to a more exposed and accessible area so we can get some data on them. It would be nice to be able to work on a bivouac thats just outside our door rather than having to hike all over this mountain to track others, which we will probably do anyway. 
After the disappointment of the army ants, we continued our hike up the side of a mountain, most of which was not cleared with a path. I can now say that I have bushwhacked my way up the side of a mountain with a machete. I don’t think it gets more field work-y than that. Eventually, we found the trail we were looking for which took us along the ridge in the cloud forest. Jesus it was just utterly breath taking. I’m not sure that pictures will do it justice but here's one anyway.

The weather was perfect for hiking in t-shirts and field pants and the sights were just so gorgeous. It was an unusually clear day for the wet season allowing us to see all the way down to El Golfo De Nicoya which connects to the Pacific Ocean. We hiked over to visit the Cambells, two of the original founders of Monteverde, who just happen to have a baby sloth...a baby sloth...A BABY SLOTH!

There is nothing cuter than a baby sloth. Even the baby goats paled in comparison. (There was an abundance of baby animals that afternoon.) The son of the two founders also just happens to make excellent goat cheese and jam. The house also just happens to be equipped with a giant rope swing. It just happened to be a really fun hike. 
Today we plan on exploring some of the trails around here on the farm we are staying on and then going to Quaker meeting (their rendition of church) just to say that we’ve done it. It’s also a great opportunity to meet people in the area, this way they will let us trek over their property to track down ants. Finding the ants seems to be the hardest part of this endeavor.

June 24, 2013
Yesterday was a good day for ants. In fact it was a great day overall. The weather was once again sunny and a bit windy (again more dry season weather which is just fine with me). The meeting was interesting, everyone just sat in pews arranged in a circle for an hour in quite contemplation. Nobody dressed up, we went in our filed gear. Jeans are only worn here on very special occasions. So we sat, and sat, and sat and then all the sudden everyone starts moving and wishing everyone good morning. It was weird, like everyone just inherently knew when the hour was up. Then there was news like birthdays and such and that was it.
We explored their library afterwards where I found a giant rhinoceros beetle (sadly no picture) and another book to read. After a hearty lunch of quesadillas, we set out on the farm next to us, the Stouckie Farm, where hiked over to the ridge and experienced the most gorgeous sight we have seen so far. I know I say that a lot but it’s true.

We also found another colony of Eciton, again it was in the base of a tree, immeasurable. Darn.
But then, as we emerge from the forest into The Lacuna Pastures, Siobhon, master ant spotter that she is, spots a small column of Eciton marching through the thick grass. As we painstakingly follow the ants, hindered by the dense pasture, we come to a large pile of fallen trees just over the barbwire fence. Kaitlin jumps the fence vainly attempting to pick up the column. Then, as I round the the pile, I see a dark shadow beneath the pile, a dark shadow that was moving. I had found our first measurable bivouac!
Not entirely prepared for such a find, we invented a system to deploy the iButtons (which measure temperature and humidity, in this case) into the pulsing pile of ants, using a stick and a hair tie. (also my idea. It was a good day for me.) We were inthralled as Kaitlin pushed the sick through the what we then discovered was a curtain of ants, not a ball. The curtain disintegrated as the stick jerked to one side. Thankfully, the ants reformed the curtain around the stick and with that our first data was recorded and with not one sting or bite inflicted. We will leave it there for four days or so though we will go and check it to make sure everything is still good today. 

(later)

As a side note, the first bivouac emigrated last night to a new location just down the trail. This new bivouac was also measurable so we deployed more iButtons this morning. 
I'll post much more later and hopefully many more pictures but the wifi I'm currently parasitizing off of is a bit slow so for now it's a bit touch and go.

Willkommen zu Deutschland

Universität Des Saarlandes: Becoming a Student

"Nächster Halt, Universität."  After one endures the awkward communication exchange with the bus driver to obtain a ticket, a German bus ride is actually quite serene.  As I passed different bus stops filled with university students, I noticed all the trees and nature that encompassed the area.  The scenes in front of me were so beautiful and calming that I escaped into my own thoughts and almost ignored "Nächster Halt, Universität," which means "Next stop,  University."

After stepping off the bus and seeing the University of Saarland's campus, I was tempted to stay for more than just ten weeks.  Of course, I did not enjoy the view of the campus for too long because I, along with my three colleagues, wanted to get started on our research at the INM, Institute for New Materials.

In our initial days at the university, my colleagues and I toured around the university and began the process of becoming an official student of the University of Saarland.  This feat entailed acquiring health insurance, bank accounts, and student ids; signing and filling out different forms; and many different steps that seemed to take a long time.  By the end of the week, we were officially students and completed the majority of the steps.

In between this process, our group conducted background research on each of our individual projects.  We read different papers on electrochemical capacitors and gleaned information from them.  Our group also learned how to conduct Raman spectroscopy and how to make test capacitors from Dr. Emilie.  Last Thursday, we observed our first lab meeting with Dr. Presser (our boss's boss in Germany) and everyone else in our group.  Dr. Atchison assisted us through this entire process and made sure everything went smoothly.

Ich Bin Verlaufen: The German Experience

"Ich bin verlaufen" translates to "I am lost" in German.  This phrase is probably one of the most useful besides "Englisch?" and "Hilfe bitte".  Needless to say communication is important.  From this experience, I realize that not everyone is going to understand what I say.  From this trip, I realize how important learning another language is not only for yourself but for other people.  Thus far, I have traveled to Bonn.  On my way to Bonn, I had an issue with my ticket and the conductor did not know English. I felt so lost and felt bad for not knowing what the man was saying.  Luckily, the girl sitting across from me, Bettina, knew French, German, and, most importantly, English.  She resolved the whole misunderstanding for me, and we talked for two or three hours.

Of course, that moment has not been the only time where I have felt "lost" in Germany.  In fact, besides feeling lost; I have been lost. When I was on the train to Bonn, I accidentally got off at the wrong station that had a similar name.  Initially, I had a thought that I was supposed to stay on the train, but I decided to get off anyway.  When I realized my best friend was not in the station, I called her on a pay phone.  I was actually amazed to find a pay phone considering that they are almost nonexistent in the United States.  Anyway, she was in a different station in the bigger city. I ordered another ticket, hopped on a train with some Ukrainians, and shortly found her in Bonn's main station.

As much as I would love to say that knowing German would probably be the most useful tool in Germany, many benefits exist with not knowing German.  For instance, I would never have met Bettina or those Ukrainian tourists if I knew German and resolved issues on my own.  By not knowing a language yet, I have had so many interesting and often comical experiences.  Of course, I do want to learn the language and will make an effort to do so in the future weeks.  Knowing different languages is not only useful for the person learning but for others.  Actually, I had the chance to return Bettina's favor in Bonn.  Some Spanish tourists were trying to communicate with the associate at the Information desk in the train station; however, the associate only knew English and German.  My best friend and I knew Spanish and translated everything the associate was saying so that the Spanish tourists understood.

Throughout most of my time in Bonn, I spent my time with my best friend exploring, window shopping, and visiting museums and gardens.  I had a wonderful time on that excursion and hope to have many more in the coming weekends.

Saarbrücken/Deutschland: Another home?

When I first arrived in Saarbrücken and saw my room, I was thrilled.  Actually, I have the best view from my room.  As of right now, I really do not want to leave this country.  With this city and even this country, there is no need to rush or hurry.  All of the stores in the city and throughout Germany are closed by 8pm.  Stores do not even open on Sunday.  The food is of better quality because of stringent government regulations.  Many buses and trains run on the "honor" system where one buys a ticket but does not have to show it.  Much of the country is covered in forests for hiking.  From what I have seen, much of the country is beautiful.  Almost every weekend, some party of festival is happening somewhere.  When I was on the train to Bonn, I saw fields of wind turbines and solar panels.  Germany's recycling system is so intense where almost everything is recycled.  If a person purchases a drink in a bottle, one can return that bottle and receive money in exchange.

Of course, not everything in Germany is perfect.  For instance, German trains do not always arrive on time and that makes transfers difficult if you only have four minutes to transfer between trains.  No unifying system exists for opening doors in Germany.  In the United States, a handle on a door means pull and a bar means push.  In Germany, it could be either way.

In the end, these little things can be overlooked by all the other exceptional practices.  I am enjoying my time here and learning a lot.  I just wonder what is going to happen this week and the weeks to come.


 

Saarbrucken Week 1

             Germany is an awesome and interesting place. The food is delicious, cheap and generally made of better quality materials. Most of the people I’ve met are very nice but they have trouble understanding me due to my total lack of German skills and my thick Philly accent. The doors don’t open in the same direction as the U.S. which has caused a couple funny incidents. Saarbrucken is also ridiculously quiet. You could probably hear a pin drop from across the University campus. I never realized just how loudly we Americans  talked until I came here.

               Also everything here closes at around 8pm this can be annoying considering we get off work at around 6pm. This combined with a crippling lack of Wi-Fi in the guest house makes going to sleep at a reasonable hour quite easy.

               On Saturday we took a walking tour of Saarbrucken including a visit to the old Schloss which has been converted in to a museum. Underneath the schloss as part of the museum you can enter the fortifications of the old castle. It was really interesting. In one of the other wings you can get a brief history of the region from its early days to post WWII.

The research is going well so far. The first week was spent mostly doing background research and dealing with paperwork. Most of the paperwork is done now and in the lab we learned how to make test capacitors and preform RAMAN spectroscopy. Next week we are learning how to use the SEM, how to electrospin fibers, and some of the principles of electrochemistry. Also I will finally get to try schwenker, a Saarlandish barbecue style that grills the meat on a pendulum over the fire.

               It’s been a great week and I can’t wait to get back to work on Monday.

Investigating Carbon Expansion in EDLCs - Week 1

Investigating Carbon Expansion in Electrochemical Double Layer Capacitors  

Alexander J. McBride

1. Introduction.

                  A sustainable global energy future will require effective energy storage. Production from prominent clean energy sources, like solar and wind, are unreliable, varying with climate conditions. Storing excess energy, consequently, is necessary for a continuous supply of energy. Additionally, as energy resources for transportation applications move away from combustible fuels, portable devices for providing electric power are necessary. Existing energy storage technology relies predominantly on batteries, which have several shortcomings. Lithium-ion batteries are commonly used due to their high energy densities (up to 180 watt hours), but such devices have high fabrication costs, slow power uptake/delivery performances, and limited lifetimes. Alternatively, electrochemical capacitors (EC) have high power densities (10 kW kg^-1), moderate costs, and longer lifespans, when compared to batteries. The main disadvantage of ECs, also called supercapacitors, or ultracapacitors, is low energy densities (5 Wh kg^-1). Despite this drawback, ECs are still ideal for load leveling of electrical spikes in inconsistent energy sources, as previously described. However, any increases in EC energy density would significantly improve such devices, allowing them to complement battery technology, and perhaps eventually replace them altogether.

There are three main types of electrochemical capacitors: electrochemical double layer capacitors (EDLC), pseudo-capacitors, and hybrid capacitors. EDLCs are designed around two carbon-based electrodes, which have high surface areas capable of storing hundreds to thousands of times more charge than conventional electrolytic capacitors. Electrostatic charge is stored in EDLCs by absorption of ions from the nearby electrode, which are subsequently desorbed during discharging. Pseudo-capacitors introduce redox reactions on or near the surface of the electrodes for charge storage. Hybrid capacitors combine ECs with a battery, to take advantage of their dissimilar properties. Factors effecting capacitance within ECs, include the specific surface area (SSA) of the electrode, the electrical conductivity of the electrode, carbon pore dimensions, and cation/anion sizes. The larger the electrolyte stability voltage window, the higher the supercapacitor cell voltage. Problems with aqueous and organic electrolytes are related to solvent decomposition at high voltages (0.9V and 2.7V). As a result, ionic liquid (IL) electrolytes are often chosen for their higher voltage capacities, despite their low ionic conductivities.

In recent years, studies have demonstrated that, after consecutively charging/discharging the EDLC, volume fluctuations in the carbon based electrodes effect ion electrosorption (i.e. charge storage). Traditionally, researchers list incredible device lifetimes, as an advantage of ECs. Electrode expansion, however, may eventually limit device cycle lifetimes. Further research is therefore required to better understand the effects of expansion, and ultimately quench any expansion from harming the long-term device lifetimes. Many factors affect the extent of expansion, including the type of carbon electrode, procedure used to fabricate the electrode, and intercalation. Now that expansion is a proven operational property of EC carbon electrodes, this investigation will vary numerable factors to eliminate expansion, truly allowing for extended device lifetimes.

2. Experimental.

2.1. Device Fabrication.

While experimental work will commence next week, based on literature reports, the procedure will be as follows:

Carbon-derived carbon (CDC) obtained via chlorine treatment of boron carbide (B₄C) was purchased from Y-Carbon In. (USA) and commercial grade YP50 activated carbon was obtained from Kuraray Co. Ltd (Japan). Electrode characterization will be completed with a N₂ gas sorption around -200 ^oC using a Quantachrome (USA) Autosorb-6 system. The Bruanuer-Emmet-Teller Equation (BET) and quenched solid density functional theory (QSDFT), will be used in calculating electrode pore characteristics. Both the working and counter electrodes will use a 5 mass% polytetrafluorethylene (PTFE, 60 mass% dispersion in water from Sigma-Aldrich) solution as the binding agent, with porous CDC and activated carbon as the material for the working/counter electrodes, respectively. This will form a carbon paste, and a roll-press will be used to form solid films. Electrochemical cells will be assembled in an Argon filled glovebox (O₂, H₂O <1 ppm) and a [Emim]⁺ [BF₄]^- (Sigma Aldrich) will be used as the IL electrolyte. It is important to note, the above procedure depicts the control electrodes, as other features will be varied later on to quench expansion.

  2.2 ELDC Characterization. Cycling voltammetry (CV) is useful for identifying some of the general qualitative properties of reactions at the electrolyte/electrode interface. By forcing the EC to selected potentials, the amount of consumed charge at each potential can be determined. Plotting said current output verses the electrode potential, is useful for assessing the performance of electrochemical devices. Conversely, galvanostatic cycling (GC) tests the cell at a constant applied current, and measures the potential response. This provides the most accurate quantitative evaluation of EC performance. 

Both CV and GV electrochemical measurements will be preformed at 20^oC with a Biologic VP-300 potentiostat. Dilatometric measurements will be performed within a temperature-controlled chamber also set to 20^oC, with an Agilent 34972 A instrument to monitor carbon expansion.

3. Results. 

To be continued….

Personal Notes

         Interesting, different, and quite come to mind. We arrived in Frankfurt, Germany, on June 16th, before taking a train to Saarbrücken. Everyone, myself included, was pleasantly surprised with the physical layout of our apartments. They are larger than Drexel's dorm rooms, include a personal restroom/shower, and the apartment building contains a fully stocked common kitchen. The first day at the INM (institute for new materials) was awesome! The laboratory facilities are incredible, and I have my own office! In practice, Germany isn’t altogether too different than the U.S., though, the accumulation of numerous little variations magnifies the overall dissimilarity. Like Philly, there are a lot of people, busses, cars, restraints, and shops. Unlike Philly, Germany is very quite, everything closes at 8pm, and failing to recycle results in the death penalty. Well...maybe not the last one, but Germany is certainly very proactive about recycling. As a quick side note, if you found my project description a bit technical, I apologize. In the hopes of publishing my research (at the end of the summer), I wrote the introduction/experimental section in a fairly technical style, which I later intend modify for publishing in a science journal. Overall, I am excited about what this summer will bring, and ready to begin my research! 

- AJM