I Have a Research Support System

The other friends in the research group all knew that Xu Qiu and Chen Wanqing were called away by Teacher Wei early in the morning.

Now seeing a new document of "Nature·Materials" in their hands, all kinds of speculations spring up in my mind.

Han Jiaying sat directly next to Xu Qiu, and asked softly, "Senior brother, what's the matter?"

Xu Qiu briefly introduced a few words: "Xu Zhenghong's research group just published an article "Nature Materials", and they broke through the efficiency of the ADA system to more than 10%..."

His voice was not too loud, just enough for everyone around him to hear.

Han Jiaying works in the organic field. After listening to the beginning, she understood it instantly, analyzed the stakes, and then gave her senior a comforting look.

Although Wu Feifei, Duan Yun, and Tian Qing are not in the organic field, they have learned from what they have seen and heard in the group meetings on weekdays, and quickly analyzed that the publication of this "Nature·Materials" article is not good news for Chen Wanqing , have comforted her.

Only Sun Wo, who has just set foot in the scientific research circle for a long time, looks confused. Who am I? What are you talking about? Why are they all comforted all of a sudden?

In the end, after being comforted by everyone, Chen Wanqing's mood was almost back to normal, but she fell into self-doubt again.

Wei Xingsi allowed everyone to discuss freely for more than a minute, until his voice gradually became quieter, then he tapped the table lightly with his knuckles and said, "Let's start the meeting, Wu Feifei, you come first."

Wu Feifei finished her review of "Research Progress in Preparation Methods of Perovskite Thin Films and Single Crystals" last week, and completed the submission on Sunday. The target journal is Adv. Sci.

In addition to writing a review, she also took Sun Wo to supplement the relevant characterization of Sun Wo's tin-based perovskite materials, including XRD, SEM, etc., and taught him data processing methods.

Her main talk today is the literature review and the prospect of future work:

"I plan to switch my research direction from the three-dimensional perovskite system to Ruddlesden–Popper (RP) type perovskite materials, or two-dimensional perovskite materials."

"More than half a year ago, there were two documents, one JACS and one ACS Nano (equal to AEM), they first proposed the concept of two-dimensional perovskite..."

"In three-dimensional perovskite materials such as traditional MAPbI3, amine organic structural units with bulky side chains are introduced, such as phenylethylamine PEA, n-butylamine n-BA, etc., to form an organic spacer layer, thereby inhibiting the perovskite material. Crystallization in the three-dimensional direction results in a two-dimensional perovskite material with only a few crystal regions and a thickness of more than a dozen atomic layers..."

"Compared with three-dimensional perovskite materials, the primary advantage of two-dimensional perovskite materials is that they have very good environmental stability and strong tolerance to water and oxygen. solvents, multi-step spin-coating to get smooth films, etc…”

"However, compared with the photoelectric conversion efficiency of traditional three-dimensional perovskite materials as high as 22%, two-dimensional perovskite materials still have a big gap in device performance..."

"Two weeks ago, Mohite's research group published an article in the main issue of "Nature", preparing a two-dimensional perovskite material with a molecular structure of (n-BA)2(MA)3Pb4I13. , increasing the device efficiency from 4.44% of the standard sample to 12.52%..."

"My idea is to use the isomer of n-butylamine, isobutylamine iso-BA, to replace the position of n-butylamine in the molecular structure in the literature, during the preparation of similar two-dimensional perovskites..."

After hearing "n-butylamine" and "isobutylamine", Xu Qiu subconsciously looked at Chen Wanqing, "This operation seems to be familiar to my senior sister." '

The senior sister met his gaze with a blank expression on her face, 'Watch your Han Jiaying go, what are you looking at me for? '

The two communicated silently, neither of them knowing what the other was thinking.

Xu Qiu turned around and thought about it carefully. Although Wu Feifei and her senior sister operate similarly, what Wu Feifei imitated was the main journal of "Nature". If the action is more agile, it is not too difficult to mix an article such as AM and AEM.

This is the benefit of hot fields. As long as you catch the hot spots, you can get high-end articles at your fingertips.

If the efficiency is further improved, we can get something like 16% or 18%, which is close to the three-dimensional perovskite system, and then cooperate with Feng Shengdong and others to do some mechanism research and the like, and even have the opportunity to be published in the major sub-journal of "Nature". , the main publications of "Nature" and "Science" are not impossible.

Of course, this kind of thinking is enough, it is not very realistic...

Because the hotter the field, the more researchers there are, and the greater the competition.

In addition, the threshold of the perovskite photovoltaic system is relatively low, and there is no need for complex synthesis like organic photovoltaics. You can directly buy the materials and mix them with a solution to make devices directly. The article cycle is usually relatively short.

When you see that someone else has published an article and developed the first generation of materials, they may have already developed the second or even the third generation secretly.

If it is really that easy to achieve a breakthrough in efficiency, there is a high probability that it will not be Wu Feifei's turn to discover it, and it is already too late.

Fields involving such a long period as organic synthesis still have the opportunity to counterattack, but it is still too difficult to counterattack such a short period as perovskite.

After listening to Wu Feifei's report, Wei Xingsi nodded, and said casually: "The idea is not bad, hurry up and do it, have you bought the medicine?"

"I bought high-purity n-butylamine and isobutylamine last week, and now they have been sent to the laboratory, and I put them in the glove box." Chen Wanqing replied.

Wei Xingsi let out a "hmm", stared at the molecular structure on the projection screen for more than ten seconds, then suddenly turned his head and asked, "Xu Qiu, how did you do the light source test on Saturday?"

Xu Qiu was stunned for a moment, wondering why he suddenly brought up the matter of the light source, but he still answered normally, highlighting the workload by the way: "We have prepared nearly a hundred samples, and all the tests have been completed, and my data has been processed. And put it in the article."

After a slight pause, Xu Qiu continued: "By the way, I have finished the draft of the NC article." Speaking of which, he was directly summoned by Teacher Wei early this morning to read the "Nature·Materials" document , I didn't find a chance to tell Teacher Wei the good news before.

"Hey, so fast!" Wei Xingsi said with a smile on his face, "We will discuss your article in the afternoon, and now let's talk about the two-dimensional perovskite. Do you think this type of structure can be characterized by GIWAXS?" Got some useful information, I don’t remember anyone else doing similar reports, Wu Feifei, right?”

"Yes," Wu Feifei nodded in agreement, "I have read less than ten articles carefully, and none of them have used GIWAXS."

Xu Qiu fell into deep thought. He hadn't thought about this aspect before, and now his brain started to run fast. While analyzing, he said:

"In the film obtained by spin-coating the three-dimensional perovskite material, the perovskite crystal region is an irregular polycrystalline structure, so the GIWAXS image is a concentric ring. The two-dimensional perovskite material, according to the literature of Wu Feifei just now In summary, it should be a two-dimensional structure similar to graphene, then..."

Xu Qiu imagined that two-dimensional perovskite material thin films form two-dimensional crystal regions during the spin-coating process, and imagined them as pieces of soda crackers.

After the spin coating is over, the biscuits may be in a nearly horizontal state, or because they are stacked on top of each other, there is a small angle with the horizontal plane. It is still very difficult to make the biscuits stand upright, and it is not completely There are no vertical biscuits, but from the perspective of probability, there are very few such maverick biscuits.

In other words, the system is not completely disordered, so GIWAXS can detect the signal.

After straightening out his thoughts, Xu Qiu continued: "The two-dimensional perovskite film formed by spin coating must have a certain tendency to stack the structure, as shown in the GIWAXS image, there will be a crystallization signal in a specific direction than other The direction is strong."

Both Wu Feifei and Wei Xingsi nodded, expressing their agreement with Xu Qiu's point of view.

Seeing this, Sun Wo nodded as well, although he didn't understand it very well.

"Okay, Wu Feifei and Sun Wo will also prepare some samples for the next light source test, about the two-dimensional perovskite system." Wei Xingsi made a decision.

After finishing speaking, Teacher Wei looked at Sun Wo and said: "After your graduation project is completed, you can also make two-dimensional perovskite. You can try the system with tin. If the system with pure tin is not easy to do, then you can We can make a mixture of lead and tin, we can do it step by step.”

Xu Qiu secretly analyzed below, it seems that Mr. Wei is planning to make a big effort in the field of two-dimensional perovskite. For a small research group like Mr. Wei, this is indeed a wiser choice.

A simple comparison will show that on one side is a large research group. The big boss has a number of small bosses, with a number of postdoctoral fellows, and a number of doctoral and master students. Dozens of people are burning tens of millions of funds to study together. a field;

On the other side is Teacher Wei's research group. Wu Feifei led Sun Wo and two people to grope bitterly. It's strange that they can produce results as fast as the big research group, so they can only find another way.

If you can’t compete with other people in a large field, you can go to a subdivided field and drink soup. In a popular field, even soup may be AM.

Speaking of it, postdoctoral fellows are very important in the scientific research circle. After all, they are paid wage earners. According to the domestic market, they are ten thousand to twenty thousand a month, so they are definitely more useful than doctors and masters.

When the boss asks you to study something, doctoral students and master students can talk about it and ask for conditions. Postdoctoral fellows have no right to refuse, but if they are in a hurry, they can also leave the station early, and the constraints are slightly less.

There is currently no post-doctorate in the group, mainly because Mr. Wei just returned to China before, and there are no articles, and the influence is not high enough.

Now that there are several high-quality articles published by Wu Feifei and Xu Qiu, there is still a chance to attract postdoctoral fellows to come and join them.