I Have a Research Support System

The villain in the video is using the pipette to perfection, as if performing a stunt.

It first stands still, presses the pipette gun, the liquid flow inside the pipette gun flies out, and falls into the vial at a distance of one meter precisely, without leaking a single drop;

Then it disassembled the pipette into parts and spliced ​​them together, and then changed to a different type of pipette to continue disassembling and splicing;

...

Although the operation looked wonderful, it was not the skill Xu Qiu wanted.

Moreover, the duration of the teaching video is very long, and it is estimated that you will not be able to finish watching it in a few days.

"System, I want to learn how to operate the pipette during spin coating, is that okay?"

[Yes, but you need to end this teaching and start teaching again. 】

"Start again, do I have to spend another point?"

【Yes. 】

"Then quit this teaching first."

[Get advice from a famous teacher, pipette gun proficiency +1%]

In the end, 500 points were exchanged for 1% proficiency, what a pit.

However, Xu Qiu was not too entangled in what had happened.

After thinking about it carefully for a while, he found that the system could not be completely blamed for this matter, it might be that he had fallen into a fixed mindset.

When using the auxiliary system before, it was based on a certain experimental operation, such as spin coating operation, so the pipette skills used in it will be limited to spin coating.

But this time there is no limitation, so what you get is the method of using pipettes covering all fields.

In order to verify his idea, Xu Qiu chose to teach the ultrasonic cleaner.

Sure enough, in the system images, operations such as material synthesis and glass bottle cleaning with ultrasonic cleaners appeared, and they were not limited to cleaning substrates.

In this way, all the skills he has learned can be extended to other fields.

It can be regarded as discovering a hidden function of the system, so the 500 points are not too bad.

"System, spend 500 points to exchange for a fifth-level 100% pipetting gun teaching, limited to spin-coating operations."

[Successful exchange. 】

The virtual image reappears.

This time the content is related to spin coating, but most of them are still temporarily unused skills.

Xu Qiu fast-forwarded and cut out those useless skills, leaving only a few skills that are helpful to him at this stage.

First, a new spin-coating method.

Before, he dripped the solution on the substrate in a regular manner, and then started the glue homogenizer;

The new method is to first turn on the homogenizer to rotate the substrate at high speed, and then quickly spray the solution onto the substrate.

A significant advantage of this spraying method is that it saves solution. The normal method needs to consume about 60-100 microliters at a time to cover the entire substrate, while the spraying method only needs 15-25 microliters.

As for the differences between the two methods in other aspects, we can only know after Xu Qiu's own experiments.

In addition, when using a pipette to transfer a dense solution, there is a problem that the solution will drip from the pipette tip. If the tip of the pipette is cut off, this phenomenon can be avoided.

Xu Qiu repeated it several times, keeping the details in mind, and then quit teaching.

[Get advice from a famous teacher, pipette gun proficiency +5%]

He got up and turned on the desk lamp, and recorded all the gains just now in the experiment notebook.

The fifth-order deduction effect of the pipette gun was not bad, so he decided to try his luck at the glue homogenizer.

Moreover, the proficiency of the senior sister's glue dispenser is 0% at the fifth level, which can be directly exchanged for advanced teaching.

"System, spend 500 points to exchange for a fifth-order 100% coating machine teaching, limited to spin coating operations."

[Successful exchange. 】

When the video appeared, Xu Qiu found that similar to the pipette gun, most of the skills were useless for the time being.

For example: refitting the homogenizer, installing a heating plate under its platform, can realize high temperature spin coating operation, etc.

In the end, he only learned one trick:

When spin coating, you can set up a two-stage process, first spin the solution at a low speed, and then form a film at a high speed.

[Get advice from a famous teacher, the proficiency of the glue homogenizer +5%]

The points were still not spent, and they returned to three digits again, leaving only 278 points.

It's really fast, and it's fast.

However, Xu Qiu felt that it was all worth it.

He now has thousands of inspirations waiting to be verified in his heart, and he can't wait to go to the laboratory to do a big job right away.

However, it is already one o'clock in the morning, and there is still class in the morning.

Hey, let's sleep well.

...

After class on Monday, Xu Qiu flipped through the literature, combined with the new skills he had just learned, and began to design experiments.

The general idea is the control variable method. He first lists the experimental conditions to be changed, including:

solvent. Alternatives include chloroform, chlorobenzene, and dichlorobenzene, all of which are commonly used solvents for preparing the effective layer, and there are three types in total.

solution concentration. Usually under the condition that the polymer can be dissolved smoothly, the higher the concentration of the solution, the better the quality of the film obtained. But the higher the concentration, the more material is consumed per spin coating, and the higher the cost. One concentration is tentatively determined for each solvent.

Homogenizer/speed. The rotational speed will affect the film thickness, and the film thickness of the effective layer is usually about 100 nanometers. 1000, 1200, 1500r.p.m. for each kind, first 600r.p.m., then 1200r.p.m., 4 types in total.

Spin coating method: normal spin coating, spray coating method, a total of 2 kinds.

In fact, there are many variables that can be changed, including donor/acceptor mass ratio, solvent annealing conditions, thermal annealing conditions, solvent additives, evaporated film thickness, and so on.

But Xu Qiu is still unwilling to introduce too many variables to increase the complexity of the experiment.

Now these four variables have a total of 3*1*4*2=24 possibilities.

Still a little too much.

He thought about it and decided to consider separately the effects of solution preparation and spin-coating methods on device performance.

The resulting final solution is as follows:

Control group (4 groups in total):

Dichlorobenzene (20mg/ml, 1:1); speed 1000, 1200, 1500, first 600 and then 1200; normal spin coating,

Experimental group A (8 groups in total):

Chloroform (10 mg per ml, 1:1), chlorobenzene (16 mg per ml, 1:1); speed 1000, 1200, 1500; first 600 and then 1200; normal spin coating.

Experimental group B (3 groups in total):

Dichlorobenzene (20 mg per ml, 1:1); speed 1000, 1200, 1500; spraying method.

As for the choice of device structure, during performance testing yesterday, he found that the device performance of the inverted structure is better than that of the normal structure, and the average photoelectric conversion efficiency of the two is 4.3% and 4.1% respectively.

Now the main purpose is to sprint the efficiency to more than 5%. Naturally, choose an inverted structure, that is, a substrate based on zinc oxide nanoparticles.

…………

Evening, lab.

Because the effective layer solution needs to be stirred overnight, Xu Qiu decided to prepare the solution first.

"Xu Qiu, why are you here?" Chen Wanqing asked.

"I have some new experimental ideas, and I want to verify them." Xu Qiu said, "Speaking of which, P3HT and PC[60]BM are not expensive, so I will use some."

"Well...it's not very expensive, it's about a thousand per gram." Chen Wanqing said, "You can use it, as long as you don't waste it."

"The price is even more expensive than gold." Xu Qiu said with emotion.

"There are too many things that are more expensive than gold in the laboratory," Chen Wanqing said, "There are even more exaggerated ones, such as the PTB7-TH donor material, which costs more than 10,000 per gram."

"It's so expensive, why don't you synthesize it yourself?" Xu Qiu asked.

"It's not impossible to synthesize it by yourself, but it may take a month or two to find out the synthesis conditions. This is equivalent to spending money to buy time." Chen Wanqing said: "By the way, do you have any new experimental ideas? tell me the story."

"Keep it secret, I will definitely surprise my senior sister when the time comes."

"Then I have to look forward to it."