Day 10 - The Final Day

Today was our very last day in the MSE Research Shadowing Program, and the last day we would be attached to our awesome mentor, Jing Feng! Today, we repeated the same experiment, as more GO chips had to be prepared for future experiments. We learned that this GO is the most important component in the making of the biosensor. The process was of similarity to the two days before, where purging had to be done before starting the experiment.

Cleaning the apparatus~

Preparation~

Sliding the GO Chips~

All set and ready~

After starting the process, we proceeded to have our last lunch with our mentor~ It was kind of him to have treated us desserts!

Yumyum~

After that, we made our way back to MSE to collect our Certificates of Participation~
The day ended with us heading back to the Clean room to finish up the CVD experiment, and also visiting another Clean Room, where white light is not used so as to avoid the different spectrum of lights. Below are some photos!

Gas Cylinder Room~

Argon Gas~

FLAMMABLE and EXPLOSIVE!

Gas Leak Detection System~

(Should there be any gas leak, the system will sound an alarm)

Dangerous Acid! HF!

(It will burn immediately when in contact with skin, but the effect will show the next day)

Lab Tech Karis~

John Ho & Jing Feng~

The two weeks at the attachment program widened our perspective, knowledge and understanding of research. We also learned the meaning of conducting a research, which can even last a few years. The hardwork that a researcher must put in, the patience that the researcher must possess, and the will to never give up. These are what helps a researcher achieve his goals, to bring science and technology to the next level, to make Singapore a better place.

Through the two weeks here, our group has met countless people, and even made friends with them. Although they might not remember us, but we would still like to thank them for hospitality and help that they have given us. .

Prof. Alfred Tok, Prof. Subbu, Prof. Tan Lay Poh, Ng Li Zhen (For organising this program)
Dr Derrick Fam (GoodFriend@Symposium)
Dr Zviad (XRD@FACTS)
Irene Heng (FACTS)
Yan Bing (Certificate)
John Ho (SEM)
Teddy (Post Grad)
Chen Hu (Post Grad)
Ee Ling (Post Grad)
Sun Cheng (CVD in-charge)
Dr Wen Bing
Dr Derrick Ang
Tan Yong Kwang (Asst. Lab Manager)
Karis (Lab Tech@RTP)
Boon Seng (Espace)
Joanne Chee (Espace)
Dr Su (Fellow Mentor)
Mr Jeffrey Toh (AJC Teacher)
Ms Valerie Tan (PJC Teacher)

AND LAST BUT DEFINITELY NOT THE LEAST!
OUR COOLEST AND FUNNIEST MENTOR...
HUANG JING FENG!!!

Without any of you, the journey we had would not have been this exciting and fulfilling. We thank you all with utmost gratitude, for giving us this chance to experience research first-hand.
Thank you!

-ChunHwee & LeonLim
-graphene4life

Day 9 - Back to the Clean Room

For today, we went back to the Clean Room to repeat the experiment using the CVD. As the project focuses on using GO Chips, we had to prepare more than one batch/set of samples. By the time we reached, Jing Feng was already preparing the set-up for the second batch, and since the experiment requires purging before we begin, we spent sometime looking around and using the computer to do some light researching and reading up.

So hardworking~

After the purging process, ensured that every part of the set-up was secured and proper, before starting the official experiment~

The reason why we always place the GO chips at the centre of the tube is because the actual heat is being focused in that area. Therefore, if we were to place it too much too the side, the heat experienced by the chips may not be uniform and accurate.

In addition, the ends have to be tightly secured, as the gas being passed through contains hydrogen gas and ethanol. If there is a gas leak, the intense heat by the CVD machine might cause the gases to react and cause an explosion!

Ethanol + Argon Gas + Hydrogen

GO Chips must be placed here~

Graphene Oxide Chips~

Sealed tightly~

We then left for lunch as the whole process would take up two hours! For today, we went back to Canteen B, where each of us had two servings of meal~

Our Second Serving of Lunch!!

When we returned to the Clean Room, there was a Lab Inspection session on going. This is where inspection and safety officers would carry out scheduled inspections at the various labs to ensure that safety is not compromised in the lab. 

Lab Inspection~

After that, two hours was over, and we had to allow the CVD to cool from 900+ degree celcius to approximately 100+ degree celcius before opening the furnace. This was to ensure that when we opened the machine, the immense heat does not trigger the fire system in the lab. Finally, we had two batches of GO Chips done!

GO Chips Before CVD (Left)

First Batch (Mid)

Second Batch (Right)

After that, it took us quite awhile to clear up, and we had to leave soon as Jing Feng had a meeting soon.

While clearing up, we noticed something that happened during the process of using the CVD. One of the tripod holder tightener had melted partly due to the immense heat from previous experiments! Imagine what will our fingers be if we touch 900 degree celcius!

Check out the effect of the intense heat!

Today was our second last day under the Research Shadowing Program. Although we may be happy that it was ending soon, there's still the feeling of sadness as our journey at NTU was ending. This meant that its the end of using high-tech apparatus, seeing cool labs, and most importantly, meeting awesome people!

Rmb to check back for our last post on the final day of our experience at NTU!

Cheers~

-graphene4life

Day 8- Precise and Intense Heat

Today, we viewed the graphene sample under a Scanning Electron Microscope ( SEM) , which was prepared yesterday on the functionalised silicon chip. It was the first time that we have seen how an electron microscope is operated and the program that runs it , therefore it expands our knowledge of microscopy . We learnt that a beam of electrons will be fired onto the samples from the electron gun positioned directly above , such that a black-and-white image is shown for analysis.

Electron microscope ( at the left)

Viewing the image captured by the SEM on screen

The program for the SEM 

The dials and buttons for controlling mechanical parts of the SEM 

The records of the observation for the 2 hour session

Use the equipment with caution!

After that, we went for a break before proceeding to the Clean Room, which stimulates the kind of environment in the Semiconductor manufacturing industry, in which the samples are sensitive to dust and foreign particles. Therefore, there is a stringent code of conduct for our attire when we wanted to go into the room for heating the chips at a high temperature. We have to wear protective smocks, hair net , gloves, face mask as well as shoe covering.

The Cleanroom which we have visited 

The shelf where the accessories are collected

Before                                                                           After 

In the Clean Room 

Pre-heating the tube in progress

The furnace heating up ...

HOT!!! 

The chips in the tube

Heating up the chips 

Notice how high the temperature( in degree Celsius) can get !

Top temp. : Actual

Bottom temp. : Based on settings 

Mixture of argon and ethanol vapor ( the liquid ethanol vapourises) passing through the tube

Carbon residue after heating

Well, after the chips have been heated, these will be observed under the SEM once again to obtain more images for analysis . From here, we have decided to call it a day .

Once again , here's another trivial question of the day !

What is the synonym of 'Pyrophoric' ?

 

The answer can be found within this poster :

The Globally Harmonised System ( GHS) shows the pictograms of the risks that we might face in a laboratory , some of which we are most familiar with would be : Corrosive, Flammable and Toxic .

In order not to get harmed , there is a need for us to understand what are the risks involved in every task that we do ( for e.g : mixing a strong acid with water, which may cause an explosion) and to plan accordingly . Safety is indeed a virtue in the field of research , and that has been widely advocated by NTU alone.



Day 7- Back to the beginning

We started the day back in the Research Techno Plaza in NTU, where we carried out a new task today. We prepared clean and dry silicon chips as the substrate for the graphene oxide, so that we are able to carry out tests using solutions of different pH like what was done in Day 5.

The centre where we were at in Day 5 and today

We collected a sample size of about 40 silicon chips and prepared a cleaning solution to wash these chips. The solution is a mixture of water, hydrogen peroxide as well as aqueous ammonia. We had to mix these chips with the solution and allow the mixture to be kept warm for a period of time.

Picking the chips out one by one~

The collection of chips to be used~

The fume cupboard in which we left the chips to be cleansed~

The procedures for the process( 1st point itself is self-explanatory)

Apparatus for pump out accurate amount of hydrogen peroxide easily~

Preparing　ＲＣＡ　cleaning solution~

The chips in the cleaning solution~

The heat plate to keep the mixture warm~

While waiting for the chips to be ready , we went to prepare the functionalising agent, which is made up of aptes as well as ethanol . This is important because the functionalised chips will allow liquid graphene to be attached to it such that it will not go off easily.

Where ethanol is kept~

The bottle of ethanol is somewhere amongst these FLAMMABLE liquids~

Aptes (White bottle) and centrifugal tubes filled with ethanol( on blue rack)

After that, we proceeded with drying the silicon chips with pressured nitrogen gas . It is truly a valuable experience, though our hands will feel sore when clamping down on a chip using a twister while the air gun is firing at it.

Warmed mixture

  

 The tank of pressurised nitrogen gas

Picking out the chip from the cleansing solution~

Drying the chip with an air gun~

Notice how the color of the surface of the chip change as it dries!

Before~

Drying in process~

After~

Placing the dried chips onto a separate Petri dish~

Now, let us show you a video on how it's done holistically!

Still halfway done here~

Look at what we have noticed when looking outside ...

What is he doing ?

Well, we would like to have such free time too :(

Eventually, we have dried up all the chips, followed by pouring the functionalising agent over these in the Petri dishes, and then we left it in the dry box for about 1 hour .

Meanwhile, time for our self-proclaimed lunch-break!

Our meals, of different cuisine ( Western, Chinese and Indian)

We managed to take a look at one of the lecture theaters in NTU~

When we came back, we proceeded with rinsing the chips with ethanol and drying them again.

Mentor drying the chips personally~

After that, our mentor obtained a bottle of graphene that was prepared the other day and performed a process known as 'drop-casting' onto the functionalised chips with the liquid graphene . Notice the surface of the chips.

The process of 'drop-casting'~

Finally, we are done for the day!

Tomorrow, we will be making our way to the Clean Room to prepare the samples for electrical analysis. So stay tuned !

Trivial question : How do you differentiate whether a given liquid is pure water or alcohol ?

Well, a picture speaks a thousand words...

Left : Pure Water
Right : Ethanol

That happens because of the extent of  how hydrophobic these liquids are~