I Have a Research Support System

The method Xu Qiu thought of was to dissolve the solvent additive DIO into the main solvent chloroform to obtain a mixed solvent, and then add the mixed solvent to the effective layer solution.

For example, 900 microliters of chloroform can be mixed with 100 microliters of DIO to prepare a 9:1 chloroform/DIO mixed solvent.

Then, 40 microliters of the mixed solvent was added to 1 milliliter of the effective layer solution.

This is equivalent to about 1.04 ml of solution containing 4 microliters of DIO, and the volume fraction of DIO is calculated to be about 0.38%.

While it's not 0.4%, it's at least a precise number.

Moreover, in this way, the whole process does not involve the measurement of less than 20 microliters of liquid, and the error of pipette measurement will be greatly reduced, because when measuring a solution above 20 microliters, a piston-type pipette can be used head, almost no solution remains, even for high viscosity DIO solutions.

Naturally, there are also disadvantages. The mixed solvent contains chloroform as the main solvent, which will slightly dilute the concentration of the original solution.

If you want to pursue perfection, you need a lot of calculations to plan the concentration of the original solution and the amount of the mixed solvent.

Likewise, the effect of this problem can be reduced by reducing the ratio of chloroform/DIO blended.

For example, if you prepare a 4:1 mixed solvent of chloroform/DIO, you only need to add 20 microliters of mixed solvent to 1 ml of the effective layer solution, and you can achieve an addition of about 0.39% of DIO, which has almost no effect on the concentration of the original solution. neglect.

Obviously, the higher the proportion of DIO in the blend solution, the less the amount needed to be added to achieve the same concentration.

It's a question of balance.

After deliberating for a while, Xu Qiu decided to unify the experimental standards and set the new standard as 9:1 chloroform/DIO mixed solvent, the concentration of the original solution is increased by 4%.

This may not significantly improve the performance of the device, but at least it can avoid the situation that high-efficiency devices have been made in the simulation laboratory, but cannot be reproduced in reality due to uncertain conditions.

Xu Qiu restarted the simulation laboratory II, and with reference to the new standard, ordered the simulation experimenters to start optimizing the device processing conditions of the highest-efficiency system for him and his junior.

Monday morning.

Xu Qiu got new data, based on his third-generation 8 series and Xuemei's second-generation B4T-6 series 3D-PDI receptor devices, the highest efficiencies were 7.50% and 6.58%, and the previous values ​​were 7.42% and 6.51 %.

Increased by 0.08% and 0.07%, so-so.

However, no matter how you say it, it's a bit of an improvement, and it's not in vain for me to invest hundreds of points in it.

Xu Qiu was not very surprised by this result, after all, after this optimization, the experimental conditions did not change much.

The increase in efficiency data is simply due to the increase in the number of experiments, and the data fluctuates closer to the boundary.

From a statistical point of view, the device efficiency generally presents a normal distribution. In theory, as long as there are enough experiments, even if the average is only 7%, it may fluctuate to 8%, 9%, or 10%. Of course, the probability of reaching 9% and 10% may be close to 0, but 8% still has a chance.

Having said that, even if by luck, 8% is made in the simulation laboratory, it is meaningless.

Unless you can have the same luck in reality, it's just a dream.

After exiting the simulation laboratory, Xu Qiu briefly washed up, then went downstairs to pick up the school girl Han Jiaying, strolled around the playground a few times, then finished breakfast, and went to the first floor of the materials together.

At 9:35, everyone was summoned to 218 by Teacher Wei.

Before the group meeting officially started, Wei Xingsi said: I'm going to Europe this Thursday. You may have heard about it. It will last for a week. When I come back next week, I will mainly go to several places for exchange and visits.

During my absence, Wu Feifei will be in charge of the laboratory. Every day, I will summarize your main work and texts to her, and then send them to me. If you have any questions, you can send me a message on WeChat. After a pause, Wei Xingsi added:

Also, if there are calls from abroad during this period, remember not to hang up. Okay, let's start the group meeting. Wu Feifei, come first.

Last week, Feifei Wu's article Calcium Chloride Additive has been submitted, and the target journal is CC. After that, she plans to return to her old career and write a review on Research Progress of Perovskite Thin Films and Single Crystals. Wiley's new publication Adv. Sci.

The positioning of this journal is similar to that of AM's sub-journals AEM and AFM, but the positioning belongs to the positioning. There are too many new journals released every year. Whether it can be successful depends on the recognition of the entire academic circle.

Otherwise, a few journals will come out at random, claiming to be the top journals of CNS, and others will not buy it, and they can only enjoy themselves and enclose themselves.

Duan Yun's work on silver nanowire-doped PVDF substrate thermoelectric devices has been basically completed. He is currently sorting out experimental data and plans to invest in Small, a subsidiary of Wiley. His previous review was published on Small.

The small journal is not bad, with TOP in the first area of ​​the category, and mostly in the second area for several small categories. Although it is not as good as AM and AEM, it is better than AELM and ACSAMI.

Tian Qing is now cooperating with Wu Feifei on the in-depth study of perovskite charge transport mechanism, and has made preliminary progress so far.

Halfway through, Wei Xingsi mentioned the matter of perovskite quantum dots. Tian Qing talked about him, but did not respond positively. What he expressed was I don't care, I just don't do it.

Teacher Wei put on a stern face, as if he was a little displeased, but he didn't say much in the end.

According to Xu Qiu's current understanding of him, Mr. Wei is ruthless and soft-hearted, and can't help Tian Qing at all.

On the one hand, she is only a master's student, so she can't use articles to block her; on the other hand, her parents are all locals in Shanghai, so if she is really in a hurry, she can directly call her parents and mother to come over and face her.

Of course, Tian Qing is not completely paddling, and she does a good job in theoretical research that she likes to do.

She is now a first-year graduate student, and she already has an article. After the work in hand has produced results, she can add another article. At least it is a total of one, and it is conservatively estimated that it has surpassed more than 90% of her classmates.

Next, it was Sun Wo's turn.

He has been in the research group for three weeks and has basically learned the entire process of device preparation. Last week, he prepared several batches of tin-based perovskite devices.

However, when Xu Qiu saw his PPT, he felt that things were not going well...

As for the efficiency, why does the table only list the molecular structure? Wei Xingsi frowned as he looked at the projection screen.

No...efficiency. Sun Wo muttered.

No efficiency, less than 1%? Wei Xingsi asked.

No, um, yes, the efficiency is 0. Sun Wo lowered his head and said in a panic.

Okay, that's why the device doesn't work. Wei Xingsi leaned back on the chair and said, Wu Feifei, have you checked it out? What's the reason?

Hmm... Wu Feifei paused, and said, The appearance of the thin film is poor, which may be the reason.

The appearance is very bad, so don't make devices, first make the film well, when you get a smooth and flat film, and then make devices, Wei Xingsi tapped the table lightly, and said in a louder voice, Got it? ?”

Understood. Sun Wo and Wu Feifei responded.

Okay, let's start next. Wei Xingsi said lightly.

When Chen Wanqing saw Sun Wo's results, she was a little gloating in her heart, Finally there is a brother who is in trouble like me, and worse than me, hahaha, but seeing Teacher Wei's attitude, he instantly languished .

She first carefully reported the device efficiency of C4 last week, which reached more than 1%, and then proposed a new experimental idea.

Although Wei Xingsi didn't have a good face, he didn't harsh her too much. He just hummed a few times and finally said, This synthesis route looks better than the previous one. Have you discussed it with Xu Qiu?

After getting an affirmative answer, Wei Xingsi nodded.

Finally, it was the turn of Xu Qiu and Han Jiaying to appear, and they respectively reported the progress of the device last week.

Hearing that Xu Qiu had reached an efficiency of around 6.5%, Wei Xingsi quickly burst into a smile, and asked, Is there any chance to make it even higher, above 7%?

Probably yes. Xu Qiu replied.

Not bad, keep going. Teacher Wei nodded encouragingly, and when he learned that Han Jiaying's system had also broken through 6%, he stood up excitedly and said with satisfaction:

Okay, very good. During this period of time, you will focus on optimizing the device, and try to make a few more batches. You can decide on the specific division of labor.

After everyone reported, Wei Xingsi sat back at the desk, switched back to a serious face, and said:

Finally, once again, after I leave this week, the laboratory will be operating normally. When I come back, I will check the progress of your experiments, especially Tian Qing, Sun Wo and Chen Wanqing.

After finishing speaking, he breathed a sigh of relief, Wu Feifei, you can order food, I won't eat at noon.

Everyone returned to 216 with their own thoughts.

It was not difficult for Xu Qiu to understand Teacher Wei's change of mood during the group meeting.

He was mainly afraid that during the period of going abroad, the students in the group would paddle a lot and not work, so he beat him.

In fact, for scientific researchers of Wei Xingsi's age, the success or failure of experiments has long been commonplace.

Students are not so angry that they knock on the table when they fail the experiment, and they are very excited when the experiment progresses. Those exaggerated expressions in the group meeting are more often used to play the role of a mentor.