Chapter 453: The recognized threshold in the field of organic photovoltaics has been successfully crossed!

After the meeting, everyone exited in an orderly manner.
Wu Feifei took Sun Wo and the others to clean up the meeting place, clean the table, move the chairs, collect the garbage... and restore the meeting room to its original state.
Xu Qiu was busy dealing with some enthusiastic students, because his question session after the morning report was only 15 minutes, so many people did not have the opportunity to ask questions, so they could only "squat Xu Qiu" after the meeting. .
Among them, some put forward specific questions in the field of organic photovoltaics, and Xu Qiu directly answered them.
Some have come to ask for copies of articles from "Nature Energy" and "Joule", and there are still quite a few people in need.
So Wei Xingsi went to his office to print out several documents and distributed one to everyone.
In addition, Xu Qiu sent out WeChat several times, but the people who asked him for WeChat, without exception, were all boys.
It was not because Han Jiaying was next to him, but because the scholars who came to the venue, except for the girls in the research group, had very few wild girls.
Xu Qiu speculated that the high probability was that all the teachers attending the meeting were men except Ma Weiwei, and the influence of male tutors with female students on business trips was not good, so they all brought male students out.
However, although domestic teacher-student love is relatively taboo, it is not strictly regulated. In foreign countries, teacher-student love is widely regarded as immoral and even illegal.
For example, when studying in a high school/university in Pretty Country, teachers in many schools were clearly asked not to give students their own personal contact information.
Moreover, the school regulations will also expressly prohibit teachers and students from dating. If this rule is violated, a tenured professor may lose the tenure.
Therefore, when students of the opposite come to the professor's office to ask questions, the professor usually opens the door or half-closes the door to answer the question, for fear that this kind of thing will affect their reputation and future.
Speaking of it, Xu Qiu went to the beautiful country Phoenix City to attend the MRS meeting afterwards, and also took two sisters Wu Feifei and Han Jiaying to attend. However, he was originally a student, so there was no problem.
In the evening, Wei Xingsi also arranged a meal and invited the teachers who had not left. The location was chosen in the business district around the school, which can be reached in less than a quarter of an hour on foot.
I don’t know if Wei Xingsi considered the tastes of people all over the country, or he is controlling his own diet. This time he did not choose the Sichuan restaurant he once loved, but chose a Jiangsu-Zhejiang restaurant named "Wangjiang Tower". Relatively light.
After Xu Qiu dealt with the "curious babies" in the venue, he took a break for a while, and followed the large group of the research team to the restaurant.
On the way, Mo Wenlin beckoned to Xu Qiu suddenly and said, "Xu Qiu, look at the next class group, they are all discussing you."
"Really." Xu Qiu casually responded, then turned on the mobile phone WeChat, and found that the number of messages in several class groups was 99+.
Xu Qiu looked at the road with the corner of his eye, while flipping through the news.
It was Tao Yan who first posted a photo taken at the venue, which is exactly what Xu Qiu told about his work in "Nature·Energy".
Tao Yan also included a caption: "Congratulations to Xu Daxue for mentioning an article in the journal Nature."
The following is a row of replies from the students, with texts: "Congratulations to Xu Qiu, worship the boss".
If there is a relatively high cold, just send a word: "membrane".
Some are lazy, just copy other people's text or send: "+1", "+2", "+10086".
There are also Doutu pictures, and some animated pictures of pandamen kneeling and patting the floor.
After a while, Tao Yan painted the scene of "Mu Xue’s question and Xu Qiu’s answer" in the group chat again, and repeated it again: "Xu Qiu suggested that Mu Xue put him in his arms..."
Soon, Mu Xue came out to refute the rumors, but despite this, it still attracted the attention of the students who eat melons, and they all expressed shock. The chat was very hot, and the emojis were full of screens.
Someone said: "I am also at the scene, the situation is basically true, and I have submitted today's incident to the onion club on campus."
Others said: "Big brother, is there still a lack of accessories? I think your suggestion is good, can you give me a chance [serious face]."
Xu Qiu didn't know how to respond when he watched the classmates praise him like this, but it would not be good to pretend that he didn't see it and choose to ignore it.
After some thoughts, Xu Qiu chose to send a total of several hundred red envelopes in several groups, saying: "Thank you for your love."
Since language can't express, then change to a more direct way of expression.
Moreover, it doesn't cost much to send a few red envelopes, but it can leave a good impression on others. These students are all future contacts, and there is no way of cooperation in the future.
Although Xu Qiu has made great achievements in the field of organic photovoltaics, if he changes careers in the future, he must start anew. If there are friends from all walks of life who can help at this time, a lot of effort will be saved.
The dinner in the evening is relatively simple, because many people have to rush to the high-speed rail to go back after the meal, so everyone did not drink too much wine, mainly eating a light meal.
After the show, Xu Qiu didn't return to the material one, but went straight back to the dormitory. It was quite tiring to have a full day of convention today.
The main reason is that he needs a high degree of concentration throughout the whole process, which is used to record some of the views of other people's speeches, or the inspiration available for use.
If it is a paddling, then listening to the conference is relatively relaxing.
During the meeting, Xu Qiu saw Sun Wo sitting in the back row with his eyes squinted. He didn't know if he was closing his eyes and rested, or he was already asleep.
In the bedroom, roommate Sun Yifan is live broadcasting.
"I came back so early today..." Sun Yifan was a little surprised, because Xu Qiuke usually didn't go back to the dormitory before ten o'clock, but he didn't continue to inquire. Instead, he turned off the live broadcast microphone while operating. The game interface said with a smile:
"By the way, you are well-known in the class today, and the section where you reply to Mu Xue is a classic."
"I just said it casually at the time. I didn't expect it to be spread out," Xu Qiu said helplessly: "Sure enough, there is Tao Yan in the place, and the gossip news can't be hidden at all."
Xu Qiu glanced at Sun Yifan's computer screen. Now the popularity of Sun Yifan's live studio has slowly accumulated.
Currently, the number of people watching the live broadcast in real time has reached more than 400.
However, as far as Xu Qiu knows, there are more prostitutes in the game live broadcast area.
More than 400 viewers, it is estimated that the actual willingness to pay may be less than 10%.
After all, you can play the game yourself, and watching other people play the game is just to have fun, and prostitution is over.
How can there be a photo album or avi fragrant of a girl who brushes airplanes and rockets to lead the lady's ragged clothes.
Of course, for the platform, the game anchor is very important, because it can attract a large number of users.
Free users are also users. In the initial stage of platform creation, the main consideration is the number of users.
The number is increased first, and then you can consider increasing the conversion rate of paying users in the future.
That is, the leeks are grown fat first, and then harvested fiercely.
Anyway, as long as the user is in the field, there are opportunities for consumption.
Maybe someday the anchor yelled at him "Old Tie 666", "Brother I want it," and then his forehead became hot and he consumed it impulsively.
Similar to a casino, the interior decoration is usually very well designed, the service is also very attentive, and even free meals are provided, and the airport shuttle bus is responsible for picking up guests.
It is to attract people to come in. As long as enough people come in, the owner of the casino can earn back these extra expenses.
It is also a bit similar to the ecology of the Krypton Gold mobile game now. The game itself is free, but there are in-app purchases.
It is to enlarge the base of users, even if only a small part of them are willing to pay, it is enough to feed their own company.
Moreover, the number of free users is large enough to ensure the gaming experience of krypton players.
After all, free players are part of the gaming experience of paying players.
Xu Qiu asked casually: "How is the live broadcast now?"
Sun Yifan responded: "It's okay. If you can stabilize the current fans, you can sign a higher-end contract next time you renew."
Xu Qiu asked, "How about the monthly salary? Has it passed ten thousand?"
Sun Yifan shook his head, "It’s not that easy to earn more than 10,000 a month. I’m a small anchor, a few thousand a month... Looks, dance anchors, they come quickly, but they mainly rely on gift sharing and basic salary. not tall."
Xu Qiu nodded: "Indeed, do it as a side job first."
In fact, Xu Qiu carefully calculated it. Sun Yifan broadcasted live for three hours a day, and had to work overtime for seven or eight hours on weekends. This workload was not low.
Just like the normal 955, it is said that 85=40 hours of work per week, but eating, resting, paid use of the toilet, and occasional paddling are also included in these eight hours. The actual working time may only be 65=30 hour.
Rounding up, Sun Yifan is equivalent to another complete job.
However, the salary income brought is barely reaching the pass line level.
The main reason is that there is no big threshold for live broadcasting, and the more difficult the job is, the more the volume will be. The final result is that most people's salary will be more miserable.
Even if the cake in this industry is very big, it is the "rolling king" of the head taking the big head, and everyone else is sharing the leftovers.
With the popularization of the Internet, the current information gap is gradually disappearing and weakening.
In a blue ocean industry, if there is no threshold and everyone can enter, within a few years, there will be a large influx of people in an instant, fighting each other, and dyeing the entire sea red.
Even fields with relatively high thresholds such as the scientific research circle are now almost rolled into a ball.
In an industry without barriers, the speed of curling will only be faster.
Xu Qiu took a hot bath, then returned to the room to check the results of recent explorations in the simulation laboratory.
There is no progress in the exploration of Y series receptors.
However, a major breakthrough has been made in the exploration of laminated devices.
According to the previous ideas, Xu Qiu applied the 1D/2A type ternary system to the bottom cell of the laminated device. By regulating the ratio of the non-fullerene acceptor and the fullerene acceptor PCBM in the ternary system, the bottom cell was precisely controlled. The current density of the top cell of the battery and the top cell, resulting in a laminated device with a more suitable current density.
In the end, the highest efficiency of stacked devices has increased from 14.3% to 15.07%.
15% is a recognized threshold in the field of organic photovoltaics, and it has now been successfully crossed!
Not only that, there is room for further improvement, for example, the ternary strategy can be expanded to other stacked device systems.
Therefore, Xu Qiu reassigned the "computing power" of the senior simulation experimenters, using 80% of the "computing power" for laminated devices, and 20% of the "computing power" for the continued development of Y series acceptor materials.
On Wednesday morning, the research team held a group meeting.
Feifei Wu and Sun Wo's perovskite team report first.
They are also responsible for the two previous tasks, translucent devices based on two-dimensional perovskite materials, and laminated devices.
Among them, the processing technology of translucent devices has been further improved, and the device efficiency has been optimized to 8%, while the average visible light transmittance can also be maintained at 30%.
After nearly a month of optimization, the efficiency can only increase by 0.5% and 0.5%, indicating that the system has little room for further improvement.
Therefore, Wei Xingsi decided to "sell" this job, planning to vote for JMCA first, and transfer to ACSAMI if rejected.
In terms of stacked devices, the problem encountered before is that the prepared stacked devices do not work directly, and the efficiency is 0%.
Now, a zero breakthrough has been achieved, and the device efficiency has reached 8%.
The specific solution is to use solvent annealing for a period of time after spin coating the effective layer of perovskite, and then proceed to the next operation. Wu Feifei speculates that this solvent annealing process can achieve a kind of "setting" Function, so that the effective layer will not be destroyed during the later processing.
Although it is almost 11%+11%=8%, it can be considered a start. As long as the device can work normally, the optimization direction afterwards is relatively clear.
Duan Yun is still the same, more leisurely.
Warwick has already sent him an official offer, which is valid for one month.
In addition, he also received an offer from a local startup company in Magic City.
The company’s main business is to make 3D printers. Small factories like this do not set the validity period, which means that as long as people can come, they are welcome at any time.
Before Duan Yun's trouble was that he didn't have an offer, but now he has too many offers, and he doesn't know how to choose.
For PhD students, the choice of the first job is very important, and it is related to the future career development.
After all, they are all at this age. Except for scientific research, the work experience is almost zero. If you don't get enough experience and exercise for the first job, it will be very difficult to change jobs afterwards.
Tian Qing still maintains a slow pace, writing an article about the work of "Research on Charge Transport Mechanism of Non-Fullerene Systems with Linearly Varying HOMO Energy Level Differences". The current progress is two and a half percent and the target journal ACSAMI.
Chen Wanqing is responsible for debugging the "first-generation film printing instrument" bought from Blue River. The instrument is now placed in the fume hood of the Jiangwan laboratory. At the same time, the senior sister and Xu Qiu, Han Jiaying and others have carried out the squeegee operation. Handover of aspects.
Xu Qiu was mainly busy with conference-related matters last week, and almost did not conduct experiments. Only he knew the result that the stacked device efficiency in the simulation laboratory exceeded 15%, and it was not good to talk about it at the group meeting.
Therefore, Xu Qiu decided to share with others what he summarized at the conference.
These contents are of little significance to him, but for researchers who are just getting started, such as Mo Wenlin and Wu Shengnan, they are still very useful.
Although they have published a lot of articles in the past six months, they are relatively "partial" because Xu Qiu only allows them to focus on research in a certain sub-field, and has relatively little understanding of other sub-fields.
Now they can just use this opportunity to let them improve their abilities in other areas.
Knowledge is always not too much, even if you don’t need it for the time being, you might need it when you write an article or do an experiment in the future.
Han Jiaying began to write articles on H5 donor materials, the target journal JMCA, and the current progress is 30%.
At the same time, the school girl also carried out related characterization of PTQ1 materials, and now the data is about 70% complete.
The data of the main lack of light source and the NMR data sent for samples were not returned.
For NMR, just wait patiently, and for the light source, there will be another test opportunity at the end of the month.
Xu Qiu didn't plan to go through the light source test this time, because basically all the members of the research team are skilled light source testers. Whether he goes or not has little effect.
In addition, neither H5 nor PTQ1, Wei Xingsi intends to send samples to NIM for third-party testing.
On the one hand, the word-of-mouth in Wei Xingsi's group has been hit, even if third-party testing is not done, other researchers will not question the results.
After all, they are the current world record holders in the field of organic photovoltaics. They have achieved 13.5%, so they will not be fraudulent on the 11% and 12% efficiency systems.
Moreover, the efficiencies of 11% and 12% at this stage are already at a relatively normal level, and many other research groups have repeated this result.
On the other hand, it is mainly to save money.
It is understandable that third-party testing charges, but the fees are so expensive that if each system is tested once, it will be a bit unbearable.
It is also a hassle to let people go and send samples in person.
This week's meeting has nothing to do with Wu Shengnan, so her work continues to be carried out in an orderly manner.
The main purpose is to continue to refine the application form of the Jieqing Fund, and by the way to guide the two undergraduates to conduct experiments on the synthesis, characterization and device testing of FOIC materials.
Wei Xingsi intends to write out the first version of the two project applications before the end of the year, so that after the winter vacation is over, he can submit them directly after making a few changes.
Because of the conference, Karen Mok only made three batches of devices, but the performance was not bad.
The first is based on the J2:PCE10:-4F system, with an efficiency of 12%+. It has started to organize articles and plans to vote for an AM sub-issue AFM.
Now, as more and more researchers are pouring into the field of non-fullerenes, many people are focusing on the ternary system. As a result, more and more people are working on the ternary system. It is difficult to be the same as in the beginning. Send AM easily.
Secondly, Mo Wenlin adopted the "introduction of the ternary system" method proposed by Xu Qiu before to optimize the efficiency of the laminated device to 14.3%.
Hearing this result, Wei Xingsi's eyes beamed.
Although it is usually said that the outlook is based on a gradient of 1%, the efficiency is really at the level of 14%. It is very good to be able to increase by 0.2% and 0.3%. It is very good to expect to achieve a large leap of 1% at one time. The difficulty is to slowly grind a little bit.
Wei Xingsi turned his head and asked, "Xu Qiu, what do you think?"
Xu Qiu said in his heart, what else can I think, I have achieved 15% here, but he said:
"I think there is still a lot of room for optimization of stacked devices based on the ternary system. For example, I can start from... these aspects. This week I plan to prepare several batches of devices by myself."
"Okay," Wei Xingsi nodded, "It just happens that all your articles have been voted. Then do an experiment. It's right to change your taste."
The group meeting was over, and in the next few days, life returned to nothingness.
Xu Qiu let the simulation experiment system continue to explore the processing technology, while personally going on the field to prepare the laminated device.
He tried to reproduce the 15% efficiency of the system in reality.
The preparation of laminated devices is more troublesome than the preparation of ordinary devices, because there are twice the effective layer and transmission layer, so the time cost is increased by about 50%.
Almost only one batch can be produced in one day, and it is a bit reluctant to make the second batch of devices.
On Wednesday, Friday, and Saturday, Xu Qiu prepared three batches of devices.
The first batch of devices may be because Xu Qiu has not done device preparation experiments for a long time. Some hand-made devices have a maximum efficiency of only 13.67%, which is not as high as Mo Wenlin's.
In the second batch of devices, he surpassed the record set by Mo Wenlin, with the highest efficiency reaching 14.52%.
In the third batch of devices, Xu Qiu directly further improved the efficiency to 15.00%.
The data measured this time is just an integer, and Xu Qiu is also the first time I have met, which is quite coincidental.
However, from a probabilistic point of view, with two decimal places, the probability that the measured result is an integer is roughly 1%. He has made so many batches of devices and it is normal to encounter it once.
At the same time, the efficiency of the laminated system in the simulation laboratory has also been further improved, reaching 15.37%.
This also made Xu Qiu feel that it was a very correct choice for him to prioritize stacked devices as a breakthrough.
Because the laminated device mainly involves the optimization of the process, the simulation experiment system has a very big advantage in this respect.
The development of Y series receptors mainly involves the synthesis of new materials, and the design of molecular structure is relatively more important.
In other words, luck or technical content is relatively large, as long as the molecular structure is wrong, it is futile to optimize the process how you want.
The current 15% efficiency data of laminated devices has finally reached a threshold in the field of organic photovoltaics, which also means that this work has reached the threshold of publishing CNS articles.
Of course, if you want to publish CNS, 15% alone is not very stable. After all, it is necessary to conduct PK across fields and other popular fields.
If it can be done higher, such as 16%, the probability of hitting the CNS will be higher.
Moreover, it takes luck to be able to enter the CNS. The attitude of the editor and the degree of approval of the reviewers are all uncertain factors.
Even ordinary academic leaders dare not say that a work they have done will definitely be published on the CNS, unless it is a Nobel-level scholar, that's another matter.
After all, CNS has a limited number of articles collected every year, and it is still difficult for millions of researchers to compete for thousands of places each year.
But in any case, Xu Qiu has achieved such results at this stage, and a major publication of "Nature" has basically not run.
Therefore, Xu Qiu intends to make two-handed preparations. First of all, it must be to optimize the performance of the laminated device, and strive to continue to break upwards, 16%, 17%, and 18%.
But if the current system is unable to break through, then contribute to "Nature" or "Science" with an efficiency of 15%.
If the manuscript is rejected or recommended to be transferred to the big magazine of "Nature", then it will be difficult to find the "Nature" related to the field of organic photovoltaics, "Nature·Energy", "Nature·Materials", and "Nature·Photoelectricity Pick one of the big magazines.
In fact, Xu Qiu had previously thought about whether to use Y series receptors as laminated devices.
The idea at the time was that I was reluctant to have the two concepts of laminate and Y series receptors in the same work, which was a bit wasteful.
Originally, the two are expected to impact the CNS system. Together, even if they can post a CNS, it will be a loss.
Despite such considerations, Xu Qiu also tried this idea in the simulation laboratory.
Anyway, make the results first, and whether or not to publish them together is the final decision.
The final result shows that the Y series acceptor is not compatible with the laminated device at this stage, and the highest efficiency is not as good as the ITIC derivative represented by IDIC-4F, and even the 15% threshold cannot pass.
You know, based on the Y series of two-element devices, the highest efficiency has reached 14.8%.
But when it is used in stacked devices, the efficiency cannot exceed 15%, so it doesn't make much sense.
Xu Qiu tried to analyze the reasons.
He thinks it may be because the Y series acceptor is too "perfect". When it is blended with the J4 donor, the effective layer film obtained can achieve excellent light absorption in the range of 300-900 nanometers, which is also the performance of the Y series system. The reason for getting 20 mA per square centimeter.
Applying such a perfect system to laminated devices, there will be such a situation:
If the Y series is placed in the bottom battery, it will absorb most of the light, and there will be basically nothing left for the top battery, resulting in an extremely unbalanced current density between the two batteries, such as the bottom battery 20+. Top battery 6.
Because it is a series connection, the final current density of the overall battery becomes 6 mA per square centimeter, resulting in a significant drop in device performance.
And if you put the Y series on the top battery, it can only eat the remaining light after being absorbed by the bottom battery. The original good performance of uukānshu.com is wasted.
It could have a current of 20+, but it may be only 12 now. The efficiency of the final device is difficult to exceed the state when it is not stacked.
In other words, the Y series can be C by themselves and can play very well without assistance. At the same time, because they are too good, they can't find an auxiliary that can match it.
And letting the Y series to play support is a little bit awkward, and it does not necessarily perform better than other professional support.
It can also be said that a stacked device is actually a combination of two less perfect devices to obtain a more perfect device.
The perfect performance of Y series materials, when placed in a laminated device, becomes an imperfection.
PS: I don’t know if the monthly pass for this month can break 1,000, so I ask for a monthly pass.
PS2: There should be more updates recently.
I have a list of chapters of the scientific research assistance system