Sunday, December 15, 2013

Day 8

It is day 8 of the programme last Friday, and it is also the last day we get to do experiments in the laboratory. This signals the impending end of the attachment programme as well as the really soon-to-be presentation.
That day, we had Zhou Rui, Dr Kong's colleague, to demonstrate to us how to make ionic liquids that are highly viscous. These ionic liquids can be used as electrolytes in lithium-ion batteries, and its high degree of viscosity allows the electrolyte to be better enclosed within the battery cell, since such viscous liquids are less fluid. These ionic liquids can be further dissolved in a polymer mat so that a damp mat is created. This mat can then be added into the lithium battery in replacement of the usual liquid electrolyte.
Autolab device with a multitude of functions
The above Autolab equipment was used when we tried to measure the open-circuit voltage of the battery we assembled using the damp mat. To further investigate the adequacy of the damp mat that we've created, it is also vital to measure the thickness of the mat. So, Zhou Rui brought us to view this incredible machine, which somehow acts like a very precise ruler, measuring the thickness of the mat down to micrometres. 
Precise instrument for measuring thickness of our mat
So that was all about the morning spent with Zhou Rui, and we sincerely thank her for her time and patience. In the afternoon, me and Louis got down to doing the slides for our presentation. Hopefully it all turns out well!

Thursday, December 12, 2013

Day 7

Yes you did not see wrongly, we skipped day 6 to move on to 7 because I was sick on the sixth day and Louis had other personal reasons to attend to. So cheer for not having to go to the optician and let us move on to the happenings of today.
In the morning we tried growing nano zinc oxide brushes on a carbon nanofibre. First step required the neutralisation of the solution containing zinc by adding aqueous ammonia. Next we place the already prepared carbon nanofibre mat in the solution. The resulting mixture is then heated in an oven at 90 degree celsius. The brush has many useful properties associated with it, due to its large surface area.
Aqueous ammonia and Zn(Al2O3)2
Next, we went on to test the lithium-ion batteries that we've prepared earlier using the machine as seen below. (FYI: the machine has been on twenty-four hours ever since March 2010!) The outcome about the capacity and stability of our batteries will require some time in order to surface. Dr Kong suggested we may be able to get the results next week.
Battery tester
Next, we managed to try out the BET machine, a machine used for testing the porosity of a particular sample. We used a carbon sample that Dr Kong had prepared previously. Apparently, the machine is able to figure out not just the pore volume in the sample, but it can also decipher the distribution of pore sizes in the sample by emitting gases under different pressure conditions. Temperature has to be cold here, which explains why liquid Nitrogen has to be used. I'm always excited with liquid Nitrogen since a nice and cool mist always appears when it's around. And the cool thing about liquid Nitrogen is that although it is extremely cold, it instead burns (rather than freezes) your hand if you were to touch it.
BET machine with ghostly hand
Liquid Nitrogen-filled tank below carbon sample
For the recreational activity of the day, our pals from another group led us to this awesome place called the Students' Activities Centre (SAC). Fantastic place really and I was entirely amazed.
Pals enjoying a game of Billard
Video gamers
Foosball, Air Hockey and Billard
Our friendly mannequin
A cosy spot to chill
The irresistible charm of Starbucks
Computers for loan
The couch potatoes
It is great that there exists such nice-to-chill spots for students in the campus. We students are so blessed.

Tuesday, December 10, 2013

Day 4 and Day 5

Yesterday was day 4 of the attachment programme, which makes today the fifth. A word to describe these two days would be 'more', since louis and myself were both able to visit more labs in the school, try out more new science equipments, brainstorm about more ideas, as well as eat more food around the campus.
Notices at a food court that made me feel glad that the consumers' safety are being cared for
Fantastic-looking meal enjoyed by Louis
As in chronology, let us begin this blog post by recapping our activities in day 4. Right in the morning, we went to basement 4 of the school to take a look at the workings of the transmission electron microscope (TEM). It is basically the extraordinaire in the world of microscopes, as its magnification can be increased to even via materials on an atomic scale (an atom is approximately 0.3nm in diameter). Somehow paradoxically, the TEM is surprisingly big although it essentially deals with small things (o.o).
Then, we went back to the lab to collect our freeze-dried 3D PAN sponge that we've electrospun last week. Upsettingly, i do not have a picture of the spongy material (oh crap!), but fret not, i'll describe, to the best my limited language ability allows, its features. Well, then again i realised that describing the material requires negligible language at all, the material entirely resembles fluffy cotton balls we have at home. The material is almost weightless, and is extremely soft that i don't think i felt it. Amazing material I say :)
After that we hurried down to the furnace room, which is a room meant for all degrees of heat. Remember the PAN polymer mat we prepared earlier? Well, we were there at the furnace room exactly for the purpose of heat-treating the PAN polymer mat to form a pure carbon mat. Prof mentioned that under high temperatures under inert conditions, these polymer nanostructures will be chemically altered to form pure amorphous carbon.
Equipment used to heat-treat the PAN nanofibre mat
Expensive-looking equipment we saw nearby. Seems ideal for heating gases.
The heat treatment had to take a few hours, and we eventually came back to the furnace room one day later (today) to collect the product. Once again, i left my camera elsewhere and shall rely on my fantastical language ability to paint an image of the pure carbon mat to you readers. It is a black, brittle, flat piece of material. If you happen to inherit itchy hands, you'll find that your fingers get a lil' black after touching the carbon mat. Be glad that this time it doesn't kill you and please do rid of that bad habit.
The next experiment we required us to deal with another microscope. This microscope is an optical microscope, which is, in other words, a-unimpressive-after-you've-seen-a-TEM kind of microscope. Still, me and louis had fun toying with it, and also received kind guidance from Dr Kong's colleague.
An optical microscope
A strand of hair under the optical microscope
Well, the rest of day 4 was spent on discussions for the ultimate presentation, BUT, we're not going to disclose anything. We're keeping the suspense alright! Just wait for it. Muahaha.

Let us chop chop and move on to day 5. Highlight of day 5: lithium-ion battery assembling.
Cranky face Louis
Smiles
Free hugs machine
Highly pure Argon gas tank 
The creepy handshake
Haha, pictures truly speak a thousand words huh? The excess of our self-obsessed pictures and the lack of the pictures of the battery assembling procedure clearly shows how BORING battery assembling is haha. Well, actually it isn't entirely boring, i only yawned 3/4 times. If I haven't remembered wrongly, the way to assemble is like this: 
Battery Base --> Aluminium conductor --> lithium electrode --> Separator --> Pure Carbon or infused with MoS2 electrode --> Copper conductor --> Spring --> Battery Cover
(FYI: We made four batteries, two of them using the carbon mat we've prepared from PAN yesterday, the other two using a sample that contains carbon and MoS2.)
A liquid electrolyte was added to within the battery as well. The battery is then sealed using a hydraulic cringer.
Following that, we then tried out the Scanning Electron Microscope (SEM) to take a real good look at our leftover PAN nanofibre mat.
Ghostly hand of Dr Kong
Lovely backdrop seen on the neighbouring monitor
A strand of PAN nanofibre as seen from a magnification of x200000
A nanofibre mess observed at x3000
As Dr Kong pointed out, the PAN nanofibre strand is not porous and that is why the fibre strand still appears rather smooth on its surface. Polyester he said, is on the other hand much more porous. For elctrospun nanofibres, the pores originate from the evaporation of solvent in the electrospinning process. I guess for different materials, there exist different extents of adhesion between the solvent and the polymer, causing different degrees of porosity in the nanofibres. For polyester nanofibres, since the nanofibres are already very thin to begin with, the pore sizes will be even smaller. Louis and I have thought of leveraging on the small pores in the nanofibres to induce greater capillary effect in polyester materials. Sounds legit, but we'll need to work on this more to make it a fully fledged idea. Oh ya, we saw this adorable graffiti in the SEM room as well.
Pigs in the best light
We're ending soon, stay with us for a niffy more please! Last event of the day: the necessary evil, the fire drill in the school of MSE. Fortunately the weather was cooperative, otherwise you'll see me tearing my head. Actually it was pretty fun though, we had selcas and also managed to visit the bottom-most floor for the first time.
The beast, the brain and the beauty
The backview of a fire warden
A photo with the fire warden
Don't be paranoid, I'm not obsessed with fire wardens. It was Louis and I had to play along.

Friday, December 6, 2013

Day 2 and Day 3

It's the third day into the programme and I find myself enjoying this attachment programme more and more. Well, to be honest, Louis and i started off pretty dubious about the programme and we were also very much unclear about the requirements. Today, I was glad to be able to attend the presentation by the JC1s (Louis had something to attend to), and that round of passionate sharing really gave me insights to the programme requirements.
But before we delve into the presentation that occurred today, let me first recall the happenings in the second day. The second day was the day we really got down to doing the experiments,  and we tried out electrospinning using a flat piece of aluminium foil as the collector.
aluminium foil collector with PAN nonofibres coated on it
Hooray, it worked and I was pretty amazed. The white shade on the silver aluminium foil is the Polyacrylonitrile (PAN) nanofibres, which are all stacked and overlapped against one another. The time taken for this amount of nanofibres to be generated was almost 2 hours, and the thickness of the PAN nanofibres mesh is similar to very thin plastic bags. The PAN mat is freestanding though, it can be peeled off from the foil and be used as a separate material. Dr Kong suggested we may be able to use PAN or other polymer mats for our presentation. This could be a viable idea, as such nanotube mats seem really useful for making fabrics. Dr Kong also mentioned that it is possible to control the number and size of pores of the nanotubes by using different polymers (FYI, the polymer nanotubes are not always strands with smooth surfaces, they can be hollow or even porous). This will allow even greater flexibility in the production of the fabric.
Besides this PAN mat, we also tried making a 3D sponge-like material by replacing the collector with ethanol. With ethanol, which has a low density, polymer nanotubes ejected from the emitter will be able to sink into the solvent, forming a 3D mesh within the ethanol.
elctrospinning set-up using ethanol collector
We've yet to see the 3D sponge being formed as we had to leave early, and the electrospinning process had to take some time. We'll get back to you soon though, with what the 3D sponge looks like. There are many benefits to this 3D sponge. The most obvious one will be that the sponge has a very large surface area due to the many nanotubes forming it. This can possibly improve the functions of certain modern appliances, one being the lithium-ion battery, as the graphene electrode may be replaced with another 3D nanotube structure that will increase rate of electrode reactions and eventually increase the power output of the battery. Well, this 3D sponge is certainly interesting, and we're still deliberating on how to utilise it in real life situations.
Yea, so that pretty much sums up day 2, though i have one last thing to mention about yesterday, that is, the food in NTU. We ate at a food court nearby in the campus, and it we were completely spoilt for choice. I ate noodles :)
Sliced Fish You Mian
Okay, so now we'll be delving into the details of day 3. Like i mentioned, there was a presentation prepared by the JC1 attachment students, and we were kindly invited to sit in as guests. Wow, those guys really set the bar up high. These juniors really know their stuff and were able to come up with brilliant ideas. I heard 5 different ideas from the 5 groups: Incorporating solar panels and windmills into water bottles to generate portable electricity; designing 'spotless' fabrics that are superhydrophobic and are easy to clean and resistant to bacteria; modifying existing bulletproof suits to better withstand bullet impact as well as to improve the ergonomics; inventing heat-up jackets that utilise flexible and easy-to-carry-around batteries; coming up with window coatings that have thermochromic properties. The ideas were entirely out-of-the-box, and prompted me to rethink about the purpose of this attachment programme. At this instant, i find myself engaging in this programme as a "kid", because kids are always learning new things, always amazed by things around them and and always unafraid to spout out their ideas, even if these ideas are entirely moronic. Probably, this programme aims to bring out the curious kid in everyone of us and to convey a strong message that you can do anything in research, all you need is an idea. The ideas that we can have they are truly limitless, just as long as we are able to think of it, it will eventually become reality.
Alright, so I guess me and Louis will really be doing something that we're passionate in, and hopefully, we will be able to emulate the standard that the JC1s have set for us.

Wednesday, December 4, 2013

First Day

The first day in the attachment programme at Nanyang Technological University School of Materials Science and Engineering has been a fascinating one. For a start, let us introduce ourselves, the owners of this blog as well as the duo team working on Materials for sustainability. Li Ling and Louis, we are, and we do hope to make the most out of this programme. Dr Kong Jun Hua is our mentor.
First impressions: the lab is a really cold place, don't forget your lab coats and protective eye wear.
Today was a day we spent getting ourselves exposed to some different equipment in the lab, and the electrospinning device was particularly intriguing. The principles are simple, a collector is placed beneath a dropper (needle-like tube that allows organic material to drip through it), then a voltage is applied and eventually a long polymer chain is formed when the droplet is elongated. Conditions are inert here. Dr Kong gave us several ideas about how we can go about using this device: we can create a two dimensional mat consisting of many polymer chains overlapping over one another, or even create a three dimensional mass that is spongy in nature. The first mat can be constructed by using a flat aluminium foil collector, while the latter 3d sponge utilises a organic solvent as the collector.
Under further heat treatments, the polymers can eventually be chemically altered to form pure carbon chains, which has many uses. Earlier, we were also taught about lithium-ion batteries which utilise thin graphite layers as electrodes. Carbon chains should be able to come in handy here. Talking about lithium-ion batteries, they actually are rechargeable batteries that can last for ages as long as the electrodes do not collapse or become destroyed. As Dr Kong has shared, it is presently a challenge to find viable alternatives for the graphite electrode that have higher capacity as well as stability. Well, we'll be rich if we knew how, but this could be something we might be working on for the presentation.
Final takeaways from today: Research is no joke, it is a serious and often boring business. Research is tough, it requires a constant inquiring attitude as well as a passion towards your area of expertise. Still, scientific research is vital, even though their effects are not immediate. It's all about knowing, bit by bit, more about the world around us. This one extra scientific journal published may eventually be of utmost relevance to future generations studying this area. We find this an especially noble cause of scientific research and we truly salute all scientists.