I Have a Research Support System

As soon as he returned to 216, Xu Qiu was stopped by his senior sister.

Student, please reject the article.

Well, I have voted.

Then come and help me, how about the synthetic route I designed? Chen Wanqing beckoned.

Xu Qiu passed Chen Wanqing's figure and glanced in the direction of the laboratory. Han Jiaying was still doing the test and seemed to have sensed his gaze. She turned her head and the two looked at each other and smiled.

'The test results of the junior sister should not be bad, so let's arrange for the senior sister first. ’ Xu Qiu made a judgment at the moment, and followed the senior sister’s guidance and sat beside her.

Chen Wanqing noticed their little tricks, but she didn't point to them. She pointed to the PPT and introduced: This time, the unit A I chose is 1,3-indanedione.

It's a new structure again, Xu Qiu casually responded, briefly observed the molecular structure of the A unit, and said: Indene, it should be the conjugated five-membered ring and six-membered ring connected in the form of fused rings. Structure, and then there are two carbon-oxygen double bonds (ketones) at the 1st and 3rd carbon atom positions on the five-membered ring, which seems to be a bit similar to the idea I said before...

That's right, I was really inspired by you. During this period of time, I designed several structures, and finally left this one, Chen Wanqing smiled lightly, as if she was quite satisfied with this structure. She turned a page of the PPT and said : This is the optimized route for the future, how about taking a look?

It's really good. Senior sister really found a good structure this time. Xu Qiu sincerely admired, and then followed her train of thought, analyzing: In the molecular structure of 1,3-indanedione, five The carbon-oxygen double bond on the membered ring can introduce cyano groups, and there are four positions on the six-membered benzene ring, which can introduce electron-withdrawing heteroatoms, such as chlorine and fluorine, electron-donating methyl groups, and even various other Weird group.

Wait a minute, merge the five-membered ring into a six-membered ring, introduce cyano groups, fluorine atoms... Xu Qiu said in surprise, Sister, this is rounding up all the opinions I raised earlier.

It was discovered by you, Chen Wanqing said with a smile, Historical experience tells me that if there is an article to be published after following my apprentice, of course I must fully refer to your opinion.

Hmm... Xu Qiu fell into deep thought. It seems that since he entered the research group, the senior sister's scientific research path has changed accordingly, and the ideas and ideas he put forward in the scientific research field usually have no problems in the general direction. There is also a mysterious system from the sky, why does it feel like some kind of halo is at work?

After thinking wildly for a while, Xu Qiu shook her head and turned her attention to the senior sister's PPT again. This time, she focused on the synthesis of unit A, and unit D chose some common commercial structural units, F8, BDT, IDT, etc.

Xu Qiu found that the synthesis route of 1,3-indanedione, the A unit, was not marked on the above, so he asked curiously: By the way, how difficult is the synthesis of this material? From the structural point of view, it should not be difficult.

It's not difficult. It can be synthesized from phthalic acid, or you can buy it directly from reagent suppliers. Formic acid is starting to introduce all sorts of groups.

The molecular structure is simple, even if it is synthesized from raw materials, there will not be too many steps, and the reaction can be easily controlled within six or seven steps, which is much easier than the previous C1/C4 series that required more than a dozen steps. Xu Qiu analyzed it, and looked at the senior sister's synthesis route again. He nodded and said, In general, I have no opinion, but what is the senior sister planning to name, C5?

It's a new system, so I plan to start over, Chen Wanqing chuckled, I'm going to start naming from CH1 this time.

Okay, as long as you are happy. Xu Qiu raised his forehead, but after thinking about it, this naming method is indeed very practical. Like his 3D-PDI system, the names of materials are very long now. Do you want to use them in the future? Try something like X1, X2?

...

There was a lot of delay with Teacher Wei and the senior sister, and when Xu Qiu went to the laboratory to find the junior, her testing work was already nearing completion.

Before he could ask, Han Jiaying took the initiative to smile and said happily: This time the efficiency of the device is very high. Brother's system has a maximum of 6.48%, and my system has 6.21%~

The performance of the device is so good. Xu Qiu looked surprised on the surface, but he was muttering in his heart: Why is there such a large deviation in efficiency? '

‘According to the conditions I reported to her before, the highest efficiency of my system should be around 7%, but now it’s only 6.48%; the junior’s own system should be around 6%, and now it’s 6.21%. In the past few experiments, I repeated it in reality according to the conditions of the simulated laboratory, and the gap between the theoretical value and the actual value of efficiency will not be so large. '

'Moreover, in this result, for several different systems, some performance decreased slightly, and some performance improved slightly. This is obviously not a problem in a general link in the device preparation, so the problem is mostly in the preparation of the effective layer. '

Thinking of this, Xu Qiu suddenly asked: Sister, when you were spin-coating the effective layer, did anything unusual happen?

Unusual situation, uh... Han Jiaying frowned slightly, thought for a while, then shook her head and said, It doesn't seem to be the case, even normal spin coating, the film obtained is also uniform and smooth, but after adding the solvent additive DIO, The color of the film will change, why did the brother suddenly ask this question, is there something wrong?

That's not true. I'm thinking about how to further improve the processing conditions of the device. Let's see if you find anything. Xu Qiu casually found a reason to deal with it, thinking to himself:

'The color change of the film, I have also noticed before that the change of the thickness of the film and the change of the microscopic appearance will lead to the change of its apparent color, but there is no obvious correspondence between the change of the color and the performance of the device. relation. '

‘Maybe the problem is not in the spin-coating step, but earlier in the solution preparation stage, or something else? '

‘It’s not impossible, the school girl was responsible for the whole process of device preparation, I was busy revising the review and didn’t watch her experiment process all the way. '

'Then the reason for the abnormal efficiency of the device this time is probably due to the differences in the experimental operation between me and my junior. After all, the experimental conditions explored in the simulation laboratory are based on my own operating habits. '

‘At least it can be regarded as a rough experimental conclusion. The PDI system is very sensitive to the experimental conditions. The experimental conditions are exactly the same, but the results are very different. '

'However, in theory, this batch of devices was prepared by the school girl for the first time. I don't know too much information on the surface, so even if there is an abnormality now, I can't ask too much. The reason behind it is still to be explored by myself, but now enter The simulation laboratory is not very convenient, let's talk about it when we go back at night. '

Next, Han Jiaying chatted with Xu Qiu while testing, and quickly finished testing the remaining few devices. There were no higher-performance battery devices. After the test, she made the highest-performance battery devices among the five systems Well labeled and saved in a dedicated box.

For cost control considerations, the ITO substrates in the laboratory are recycled.

However, high-efficiency devices are not listed here. They will be temporarily stored in a foam box specially placed for ITO substrates. For easy search, the test time and efficiency value will be marked on the edge of the back of the device with a marker pen.

They will not be taken out until the article is published, or devices with higher efficiency in the same system are born, and they will be taken out and rebuilt.

After copying the experimental data, Xu Qiu casually copied the foam box storing high-efficiency devices, the remaining solution used by the school girl, and her experiment notebook into the simulation laboratory.

Afterwards, the two returned to the office. They separated the data they had obtained and handed over their respective systems to their respective responsibilities. This was to allow both of them to have data to report.

Use ORIGIN software to draw the J-V curve, and then copy it into the template with a photoelectric parameter table and a synthesis roadmap, and the group meeting PPT is completed.

With good efficiency data support, the production pressure is not great.

After completing the PPT for the group meeting, Xu Qiu didn't stay long and greeted Han Jiaying. The two left the laboratory early, about an hour early.

In fact, the rest of the scattered time can't do any experiments. Normally, Xu Qiu would read the accumulated literature, but today he has more important things to do.

Back in the dormitory, Xu Qiu and Tao Yan chatted for a while, and then they went to the student bathroom to make an appointment for a bath.

After returning, Xu Qiu lay on the bed, entered the simulation laboratory, and began to explore the reasons for the deviation in efficiency.

To be on the safe side, he simultaneously opened the experimental records kept in the simulation lab II and the experiment record book of the junior, and first checked whether the conditions obtained from the simulation lab were consistent with those of the junior during the experiment.

In my system, the corresponding condition for 7% efficiency is...the condition for the school girl to operate is...the two are the same.

The school girl's system...the two are the same.

At least that's what's written in her experiment records, and the simulated lab records won't go wrong.

In this case, I can only experiment and try it myself.

Speaking of which, the simulation laboratory I has not been used for a few days, and I still miss it.

Xu Qiu muttered, transferred to the simulation laboratory I, chose the system of theoretical 7%, actual 6.48%, used the remaining solution of the junior, and spin-coated three pieces of the same device structure according to the conditions provided to the junior. Put the substrate into the evaporation cabin for evaporation.

Turn on the mechanical pump and the molecular pump to vacuumize.

With his current permission level, after turning on the 8x acceleration, the glove box instantly vibrated at a high frequency, forming afterimages like a convulsion.

Fortunately, Xu Qiu is the absolute master in the simulation laboratory, directly shielding the perception of sound, otherwise he would probably be harassed to death by the overwhelming sound of duang and duang.

Not long after, the vapor deposition was over, and Xu Qiu got three shiny silver devices.

start testing.

6.52%, 6.61%, 6.47%.

This is the highest efficiency of the three-cell device, and it can be seen that the repeatability is still good.

It is not surprising to have such a result. During the spin coating process just now, he perfectly controlled each operation process, almost exactly the same.

The conclusion now is obvious. Compared with the original 7% efficiency corresponding to this condition, it is closer to the result of 6.48% of the school girl.

It seems that there should be a problem in the preparation of the solution.

Xu Qiu picked up the glass vial with a green cap and a dark brown body, while turning the green cap on its head, thinking.

On the cap is the beautiful handwriting left by the school girl X8, CF, 0.4%, 1:1.5, 9, 3.24

The X8 here actually refers to Xu Qiu's third-generation 8-series 3DPDI molecule. The full name is PDI3-BX-Se-8. If you write an article later, you should simplify it, after all, it is indeed too long.

The rest is easy to understand, CF is chloroform solvent, 0.4% is the volume fraction of DIO, 1:1.5 is the D/A mass ratio, and 3.24 is the date of solution preparation.

If there is a problem with the preparation of the solution, the most likely possibility is... Xu Qiu suddenly realized something, and quickly returned to the simulation laboratory II to read the full version of the experimental data.

Keeping other experimental conditions unchanged, the dependence of photoelectric conversion efficiency on the volume fraction of DIO DIO (PCE) is: 0% (5.24%), 0.1 (6.18%), 0.2% (6.33%), 0.3% (6.58%) ), 0.4% (7.01%), 0.5% (6.87%), 0.6% (6.75%)...

From 0.4% to 0.3%, the volume fraction of DIO deviates by 0.1%, and the efficiency drops from 7.01% to 6.58%. Looking at this trend, if the amount of DIO added is around 0.25%, then the efficiency value is likely to be around 6.48%. Xu Qiu analyzed it, then snapped his fingers suddenly:

The scheming frog keeps touching your belly, there must be a problem when DIO was added!

He recalled his own experimental operation. When adding DIO, he used a pipette gun with a range of 0.5-20 microliters. If the solution is 1 ml each time, the 0.4% is only 4 microliters. If the solution is only For hundreds of microliters, the amount of DIO added is even less.

And DIO is a liquid with a high viscosity. During the transfer process with a pipette, there will always be a part of it remaining in the tip of the pipette.

Theoretically, when the pipette tip is designed, it will take into account the residual liquid. For example, if the scale is 10 microliters, it may actually draw 11 microliters, and the extruded is exactly 10 microliters. There is 1 microliter residual.

However, this design is usually for low-viscosity fluids. For high-viscosity fluids such as DIO, it is possible to absorb 11 microliters, squeeze out 6 microliters, and leave 5 microliters, which will cause a large gap between theory and practice. deviation.

Xu Qiu made devices in reality a few times before. When adding DIO, he didn't think too much. Seeing that he couldn't squeeze out the liquid in one shot, he just squeezed out the liquid in the tip of the gun, waited for a few seconds, and then squeezed out again. Repeated many times. Once, make sure that all the DIO is added to the solution, and then this practice was learned by the simulation experimenters, and used in the subsequent simulation experiments...

As for the technique used by the school girl during the experiment, Xu Qiu guessed that it might be different from his. It might be that after absorbing DIO, she only squeezed it out once, so that the actual amount of DIO she added was less than when he added it, resulting in a corresponding difference in device efficiency. offset.

Whether it is himself or a junior, the operation method of measuring DIO is a bit rough, and the error is too large.

For the previous PCE11 systems, they have no demand for DIO solvent additives, so there is no concern in this regard;

However, the current PDI system is very sensitive to the amount of DIO added, so we have to consider this aspect.

After all, Xu Qiu's goal is to increase the efficiency from 7.4% to 8%, hitting the world record.

You need to do your best in every detail.

Xu Qiu pondered for a long time.

Yes!