I Have a Research Support System

It was past ten o'clock when Xu Qiu returned to the dormitory.

Another day in the cold shower.

Xu Qiu was thinking about the project while taking a bath.

When the senior sister handed him the project materials, he was stunned.

Except for an opening report, there is nothing, and the progress of the experiment is 0.

The title is Fabrication and Characterization of Organic Solar Cell Devices Based on Flexible Substrates.

He needs to find literature, design experiments, conduct experiments, and write reports by himself.

However, after this project is completed, it can be directly used as a graduation project, and it can also get a labor fee of 2,000 yuan, which is still a steady profit.

Of course, it is estimated that he will not have time to start this project until after the summer vacation. Now he still has a lot of things to deal with, such as teaching sister spraying, exams, postgraduate summer camp...

…………

Wednesday afternoon, lab.

Xu Qiu, you are finally here. Chen Wanqing said, Come and teach me how to paint.

Sister, you are in such a hurry. I haven't made the zinc oxide substrate yet, Xu Qiu said.

I'm going to paint a set of glass sheets first, and measure the UV-vis, that is, the light absorption performance of the film. I guess that the spray coating method may have improved the crystallization properties of the polymer inside the film. I want to take a look at its light absorption spectrum first. .” Chen Wanqing said.

Sure, less than a day has passed, and you have found out the reasons for the improvement of device efficiency. Xu Qiu said.

It's just a guess. Chen Wanqing said.

Okay, come on. Xu Qiu said.

...

This time it was Chen Wanqing who entered the glove box, and Xu Qiu who was guiding outside.

Glass sheets also need to be cleaned before spin coating, but Xu Qiu washed a lot during the last spraying practice, so there are still dozens of sheets in the glove box.

Xu Qiu saw a Petri dish turned upside down on the heating and stirring table, and six bottles of solution were inserted in the bottle rack above it.

He noticed that the handwriting on the bottle belonged to Chen Wanqing, so he said curiously: When did the elder sister make the solution, I didn't find it.

After I went back last night, I kept thinking about your spraying method. What is the reason for the increase in efficiency? Later, I guessed that it was the crystallization of the polymer. I wanted to verify it today, Chen Wanqing said:

But the previous preparations were all dichlorobenzene solvents, so I went back to the laboratory last night to prepare these six bottles of solutions, using chloroform solvents.

Then it's past twelve o'clock in the morning after finishing the experiment. Xu Qiu said.

That's right, but I'm not talented enough in experiments, so I can only make up for it through hard work. Chen Wanqing said.

At least my sister's talent in theory and data analysis is not bad. Xu Qiu comforted.

Hey, I think so too. Chen Wanqing smiled and started the experiment.

She clamps the glass piece, puts it on the platform of the homogenizer, and then adjusts the speed.

Xu Qiu, what speed do you think is appropriate?

2000, I haven't made a device yet, and I don't know how suitable it is.

Okay, let's make it 2000.

She then attached a pipette tip to the pipette and cut the tip in two with a click of scissors.

One piece was still on the pipette, and the other was missing.

Sister, is this how you cut the head of the gun?

Didn't you teach me to cut from the middle, what's the problem?

There is no problem with the section on the pipette, it can be used directly, but what about the other section?

She rummaged in the glove box for a while, finally found another section on the reagent rack, picked it up and threw it into the trash bag.

Sister, when you cut it, don't use too much force, or it will fly very far.

Yeah. Chen Wanqing nodded.

Then, she sucked up the solution, pressed the start button, and sprayed out the solution in the pipette.

After the end, it was found that half of the area on the substrate had not been painted, and the painted part was still layer by layer.

Ah, how could this be? Chen Wanqing looked at Xu Qiu with a look of asking for help.

Xu Qiu had a headache, and analyzed her operation problems one by one for the senior sister:

First point, it takes about 1 second for the homogenizer to accelerate from rest to 2000 rpm, so wait until it stabilizes at 2000r.p.m. before spraying out the solution;

The second point is to quickly spray the solution from the pipette gun at one time, otherwise it will cause layering of the film. Imagine a high-speed rotating substrate, and the solution will form a film on it quickly, but slowly. Spraying the solution is equivalent to spraying the solution multiple times to form a multi-layer film;

The third point is that when spraying the solution, the hand holding the pipette should not shake. If the shake is too large, it will cause multiple film formation, resulting in stratification;

The fourth point is the position and angle of the pipette tip. The angle is preferably 45 degrees to the substrate. It is difficult to describe the position directly. How about this, senior sister, pick up the pipette and I will guide you in real time .

Chen Wanqing picked up the pipette, and Xu Qiu began to guide:

Stay forward, move forward, ok, stop, move to the left, is it left or right, ok, stop, and then the angle is wrong, it's almost 60 degrees, press down a little bit, ok, that's it Position, hold still for thirty seconds.

30 seconds later.

Have you learned it, senior sister? Xu Qiu said.

Probably, learning is useless. Chen Wanqing said.

Continue to practice, let's test the results. Xu Qiu said.

OK.

The first piece, slightly blemished, was not spin-coated about a fifth of the way.

Throw it away. Xu Qiu said.

Why, the photometric absorption performance does not need to be fully covered. Chen Wanqing asked.

Xu Qiu didn't speak.

Okay. Chen Wanqing said weakly, picked up the piece of glass and threw it into the trash bag.

The second piece, N-layer film.

throw away.

The third piece, double-layer film.

throw away.

Fourth tablet.

This piece seems to be fine. Chen Wanqing said a little excitedly.

Look carefully. Xu Qiu glanced at it and said.

Wait a minute, this is not a glass sheet, but an ITO substrate. Chen Wanqing put on an aggrieved expression, and then threw it into the old substrate box.

On the fifth sheet, about a quarter of the area was not spin-coated.

throw away.

...

Senpai made all kinds of mistakes in a cycle like this.

Xu Qiu was in a hurry outside the glove box, wishing he could get started and teach his sister to do the experiment, but there was a thick layer of explosion-proof glass blocking it.

He suddenly understood Teacher Wei's feelings when he was teaching his sister.

Fortunately, after scrapping more than 20 pieces of glass and adding an ITO substrate, the senior sister finally succeeded in continuous spraying and obtained six sets of relatively perfect film samples.

Senior sister, you almost used up all the glass pieces I washed earlier. Xu Qiu complained.

Well... at least the result is good, Chen Wanqing said shyly, I'll test UV-vis later, do you want me to learn it?

Okay, when I get down, I'll clean the substrate first. Xu Qiu said.