I Have a Research Support System

A few days later, Xu Qiu got the test results from the simulation laboratory, and the performance of the device continued to make breakthroughs.

The best system is PBDB-TF: IDIC-4F, the highest photoelectric conversion efficiency can reach 13.52%.

Considering that the PBDB-TF donor material also performed well in other non-fullerene systems, Xu Qiu decided to identify it as a benchmark donor material.

This brings us to a naming problem.

On the one hand, the name PBDB-TF is a bit long; on the other hand, the original PBDB-T material is the result of other research groups, and Xu Qiu also has some selfish intentions to remove this imprint.

In the end, Xu Qiu imitated the school girl and developed the FTAZ series from H1x to H4x, and named the three new PBDB-T derivatives, PBDB-TS, PBDB-TF, and PBDB-TSF, respectively as J1, J2, and J3.

As for Han Jiaying, now H is used, and J is also used. In the future, a new system can be named Y series. I have to say that a name with three characters is good.

Xu Qiu is not very interested in this method of using his own name. Otherwise, he could simply call the ITIC series X1 directly. It is possible to do so, but it is not necessary.

Having said that, Xu Qiu doesn't plan to devote too much energy to the donor at this stage.

Because he now has a lot of experimental data, and these experimental results show that for the organic photovoltaic system of "wide band gap donor: narrow band gap acceptor", the donor material is mainly the icing on the cake, and the performance of the device mainly depends on the acceptor Material performance.

For example, the IDIC-4F system, the combination of IDIC-4F and J2 has an efficiency of 13.52%, but it is also not low when combined with H43, J1, and J3, and the efficiency is 11.92%, 12.27%, and 12.98%, respectively. Even if it is combined with light Combining non-complementary absorbing narrow bandgap donor materials PCE10 and PCE11, the device efficiencies both exceeded 10%.

The feeling to Xu Qiu is that if the receptor material is very good, the requirements for the donor material will be relatively low, as long as it is not too much hind legs, it is similar to an advantage called "a dog with a tie can win", here It is "any donor material will do", after all, the narrow band gap non-fullerene material is the main contributor to the photocurrent of this system.

In fact, the IDTBR system reported by Xu Zhenghong and his colleagues used a variety of standard donor materials to show high device performance. At the time he was right.

Xu Qiu summarized his work on the J2:IDIC-4F system with several highlights.

First, it is naturally high efficiency. Compared with the previous world record of 12.21%, which was stuck for three years, the device efficiency has increased by 1.31%, which is not a small margin.

Second, similar to the previous IDIC system, the IDIC-4F system can also be made into a thick film, such as a 300nm effective layer film, and the device efficiency can be greater than 10%.

Third, the efficiency of large-scale devices based on this system, such as devices of 1 square centimeter, can also reach more than 10%.

The second and third points can be combined together and then integrated with the inferences of the previous IDIC system, namely:

"Change of side chain → decrease intermolecular hindrance → tight arrangement of acceptor molecules in the effective layer → increase of electron mobility → thick film and large-size devices can be prepared, energy loss is reduced, and open circuit voltage is increased"

"Introduction of fluorine atoms → enhanced intramolecular interaction → deeper HOMO/LUMO energy level of the acceptor material, red shift of light absorption → increased short-circuit current and increased open-circuit voltage"

If this is the case, it not only puts forward some new viewpoints, but more importantly, it solves a problem that has plagued the field of organic photovoltaics for many years, because although there are systems that claim to be able to make large-sized and thick films before, the efficiency is relatively low. No more than 10%.

Examples of high efficiency are always more convincing than examples of low efficiency.

Moreover, for a field where the highest efficiency record is around 12%, and most systems are below 10%, breaking the efficiency of 10% also has unique significance.

However, Xu Qiu was really confused about the positioning of this job and which journal to submit to.

Because in the academic circle, the top journals such as AM and the major sub-journals of "Nature" and the top journals at the CNS level have a very large middle span, and basically there are no transitional journals.

It is hard to say whether the current job will be published in the major sub-journal of "Nature". Maybe it will be 50-50, depending on the editors assigned and the reviewers selected by the editors.

After all, Wei Xingsi is a newcomer to journals of the level of the "Nature" major sub-journal. Although he has mixed a few "Nature" major sub-journals through PY, they are all caught among the four, five, six or seven authors, and there is no existence feel.

But for this level of top journal, if the corresponding author does not have a halo, it is really a bit false.

If you select for "Nature·Materials" and "Nature·Optics", when the reviewer's comments come back and you are directly transferred to NC, it will be a bit embarrassing.

Although NC is not bad, after all, a large part of the manuscripts that can be published in NC are for "Nature" or the major sub-journals of "Nature". This is why some scholars believe that NC is slightly higher than AM and JACS.

However, if such a breakthrough job is transferred to NC, Xu Qiu will be a little bit unwilling after all.

If the performance of the device can break through to more than 14%, it will be relatively stable.

It is a pity that the results obtained in the simulation laboratory are getting closer and closer to the optimal conditions. Basically, what is measured is the same as in reality. It is still difficult to increase it by 0.5%.

Xu Qiu estimates that the current J2:IDIC-4F system is likely to be close to the performance ceiling of single-junction binary organic solar cells based on ITIC derivatives.

If you want a breakthrough in efficiency, you must either make major changes to the existing ADA non-fullerene system, or make a double-junction stacked battery device.

However, these are two other stories, which have nothing to do with the current job.

In the end, after much deliberation, Xu Qiusi decided to aim for a new journal of the same level as "Nature·Materials" and "Nature·Optics".

New publications mean that there are more opportunities. After all, there is a lack of manuscripts, so the quality requirements for manuscripts will not be too strict.

Xu Qiu generally has two goals, one is the latest major sub-journal of "Nature" "Nature Energy", and the other is the new journal "Joule" of "Cell" Publishing House, both journals are new journals that target energy , is highly related to the field he does.

Among them, it is worth mentioning the journal "Joule".

Joule is known to those who have basically studied physics in middle school. Although he may not be as famous as Newton and Einstein, he is undoubtedly a person in the first echelon of the scientific community.

He is a physicist in Great Britain. He discovered the conversion relationship between electric energy and heat energy in 1841, which was later called "Joule's law", that is, the heat generated by the current passing through the conductor is proportional to the square of the current and proportional to the resistance of the conductor. Proportional to the power-on time.

Later, "Joule" was also designated as the international unit of energy and work. 1 Joule energy is equal to the work done by moving the point of action of 1 Newton force 1 meter in the direction of the force.

"Cell" Publishing House named the new journal "Joule", obviously it is not a small plan, and it may plan to wrestle with "Nature" and "Science". There, the reputation has accumulated long ago, and even many ordinary people in China know the names of these two journals.

But in any case, under the strong promotion of "Cell" Publishing House, the influence of "Joule" can still be compared with that of "Nature".

After finalizing the basic plan, Xu Qiu said with emotion to himself:

"J2 and IDIC-4F have been synthesized on my side. In reality, it has just stayed at the stage of J1 and IDIC. It seems that after the vacation is received, we will have to catch up with the progress."

"Besides, there are quite a lot of things to do after school starts, not only to do the J2:IDIC-4F system, but also to start exploring translucent and laminated devices, and to be busy with the Jiangwan laboratory renovation and future laboratory relocation , A few days ago, I promised to go to Blue River to give technical guidance."

"It really hurts to think about it."

During the summer vacation, Wei Xingsi did not harass Xu Qiu much, but sent him a few review papers from AM and JMCA, as well as some newly published literature. The two articles submitted before the holiday, AM and Angew, had already been submitted for review, but No comments have been sent back yet,

When reviewing manuscripts, Xu Qiu just looked at them casually. He is more Buddhist, and he is generally not very good at rejecting people. He is not the kind of tough (strict) reviewer.

AM's article is the work of a foreigner. They are doing all-polymer organic solar cells. The system is similar to N2200. They made a ternary conjugated copolymer based on N2200 and introduced 5% of N2200 molecules. The rigid main chain has increased the device efficiency to more than 9%, breaking the world record of an all-polymer organic solar cell. The previous world record was about 8.0%.

The work of this foreigner is relatively rigorous, and the data is very detailed. There are more than 20 pictures in the supporting information, all of which are listed in Figure S22.

In the end, Xu Qiu put forward a few opinions, which can be regarded as "minor reforms".

According to Xu Qiu's perception of the scientific research circle in the field of organic photovoltaics, the articles published by Asian scientific researchers are generally relatively watery. Except for the core highlights of the articles, other places are basically more routine. what story to tell.

On the other hand, scientific research workers in Europe and the United States, relatively speaking, the workload of each job is not small, and in many cases there will be more "private goods", or the opinions are expressed in the papers, so reading their articles will not be easy. It is more troublesome.

The all-polymer organic photovoltaic system is now the only material that can be named by name, and there is only one kind of N2200, and other materials are basically on the street.

In fact, after Xu Qiu developed ITIC, he also had inspiration and thought of making ITIC into a polymer form.

The structure of ITIC is ICIN-IDTT-ICIN, then introduce a single bromine atom on ICIN, and then directly carry out Stille coupling reaction with bistrimethyltin-substituted thiophene, and the structure can be obtained as [ICIN-IDTT-ICIN-T] n polymer acceptor material.

The difficulty of synthesis is not too high, as long as chlorine and fluorine atoms are replaced with bromine atoms, after all, ICIN-Cl and ICIN-F have been obtained before.

Spend some energy, maybe you can also post one or two AM-level articles.

However, in the end, Xu Qiu did not choose to explore this possibility by himself. After all, the field of polymers is completely unfamiliar to him.

Xu Qiu's scientific research philosophy is to focus on one direction to achieve the ultimate, interlaced like a mountain, crossing too many boundaries, it is easy to mess up.

Anyway, there are many researchers in the world. If Xu Qiu has developed a system with great potential such as ITIC, others will naturally follow suit and complete the research in various sub-fields.

Maybe not every researcher has the ability to develop CNS, but since he is mixed in this line of work, he still has the ability to follow the trend of the big guys and eat soup.

Another JMCA review is the work of Xu Zhenghong's research group in China.

They are still based on the IDTBR system, but the efficiency is not as high as other IDTBR systems, only 7.2%, which is probably why they voted for JMCA.

Xu Qiu saw that there were no major problems with their work, and 7.2% was not particularly low at the current stage, so he didn't stop them, and made a few comments, which were also considered "minor changes."

However, Xu Qiu reckoned that Xu Zhenghong and the others wouldn't be able to produce any heavyweight results in a while.

After all, a molecular structure like IDTBR has limited regulatory space:

First of all, unit A is Raodanine, unlike ICIN, which has many active sites, and molecular modification is not easy to change;

The second is the π unit and the BT unit. The work of introducing fluorine atoms has been published, and there is not much room for other optimizations;

As for unit D again, the side chain regulation of IDT has also been done.

All they can do is completely replace the D unit, which is the skeleton structure of the IDT, such as replacing it with an IDTT or other structures, but doing so is very risky, and it may not necessarily achieve benign results.

In addition to these two review papers, in the latest published literature, Xu Qiu saw that other researchers are also following suit and developing ADA-type non-fullerene acceptor materials based on ICIN units.

There are two jobs in total, and the corresponding authors are all domestic acquaintances, one is Gong Yuanjiang, and the other is Bao Yuanyou.

Not to mention Gong Yuanjiang, he was reminded by Teacher Wei during the meeting at Kainan University, and later because of Mo Wenlin's relationship, he also got a lot of inside information.

Bao Yuanyou's words surprised Xu Qiu slightly. Before that, he was the one with the worst speech level in the exchange meeting, but now it seems that his sense of smell in academics is quite keen.

The two jobs are both following the IDT-ICIN system of the senior sister. After all, Xu Qiu's ITIC system has just been published on AM, and it is still necessary to "let the bullets fly for a while".

The material efficiencies of Gong Yuanjiang and Bao Yuanyou are not high, only 5.22% and 6.73%, respectively published in "Macromolecules" and AFM.

Seeing that Bao Yuanyou's work was published on "Macromolecules", Xu Qiu couldn't help but feel that the titles of journals in the academic circle are really formalized.

This ADA non-fullerene material is obviously a small molecule. As a result, this work can be published in the journal "Macromolecules".

Of course, if it is forced to say that the donor material is a polymer or a macromolecule, it makes sense.

Two weeks of summer vacation passed by, and it was time to go back to school again.

Xu Qiu once again stepped on the green leather train to the magic capital.