I Have a Research Support System

Seven o'clock on Thursday morning, dormitory.

Xu Qiu opened his eyes on time and looked at the other two berths. Tao Yan's place was empty and there was only one quilt. Now he should be alive somewhere on the earth, while Ren Bin was still screaming. sleep.

After some calculations in my mind, after more than ten hours, the results of the simulation laboratory II should have come out.

Thinking of this, Xu Qiu jumped up from the bed, went to the bathroom to wash his face, then lay back on the bed, rubbed his hands, and entered the simulation laboratory.

Sure enough, the device performance exploration of several new materials has been completed. At present, the simulation experimenters have started the second priority task arranged by Xu Qiu yesterday, and are conducting synthesis experiments.

Xu Qiu hurriedly looked at the results of device performance.

The more you look at the result, the more pleasantly surprised you are, what a bumper harvest!

The highest efficiency reached 10.12%!

It is equivalent to the IDTBR system reported by Xu Zhenghong's research group in "Nature Materials" that was just published!

Xu Qiu couldn't help but start to imagine that if he could get the current results half a year or a year earlier, it might be him and Teacher Wei's research team who published this "Nature·Materials" article.

However, there is a high probability that it will be more difficult.

The publication of an article at the level of a major sub-journal of "Nature" not only depends on how well the current work is done, but also on the previous work, and the bonus of the corresponding author will also play a very important role.

For example, before Xu Zhenghong's research group published this "Nature Materials", they created the field of ADA and published a lot of research work. Although it can be understood as irrigation, why not also promote the development of this field? .

After all, except for the subversive discoveries, such as the use of tape to prepare graphene, most fields want to develop a little bit. What we see is the final IDTBR. Where we can't see it, there may be more There are several others, dozens of unknown structures.

As for the bonus of the corresponding author, it is also easy to understand.

Because of the "peer review" mechanism, it is easier for the big guys to pass the manuscript, but if the ordinary scientific researchers want to get ahead, they have to put in more effort and get better results, such as this work of IDTBR , if another ordinary scientific researcher submits a manuscript, the reviewer's opinion with a high probability is "recommended to switch to NC", and in the end only one "Nature Communication" can be published, and the grade will be a bit worse, unless the efficiency reaches 11%. , or even 12% to have a chance to appear on "Nature Materials".

To say that this system is unfair, and it is indeed unfair, the boss has privileges.

But there is no absolute fairness in this world, and it is very difficult to maintain relative fairness.

You must know that most of the bigwigs also climbed up step by step from ordinary scientific researchers before becoming bigwigs.

Didn't there be that torture from the soul: "Why should the hard work of three generations of my family lose to your ten years of hard study?"

The principles are common.

On the other hand, the "Nature Materials" published by Xu Zhenghong's research group has also affected the difficulty of publishing papers in "Nature" major sub-journals in the field of organic photovoltaic non-fullerenes.

Such a popular journal needs to take into account work in different fields, and it is impossible to repeatedly publish too many articles in the same field, unless it is a very popular field, or a certain field has made major breakthroughs in a short period of time.

Now, Xu Qiu's 10% efficiency can be called a breakthrough, but not a major breakthrough.

Putting aside the distracting thoughts in his mind, Xu Qiu began to analyze the data carefully.

In any case, as a researcher, the most important thing is to do your job well.

There are a total of J-V data results of thousands of devices. It took Xu Qiu half an hour just to analyze these complex data, and he also got a lot of conclusions:

First, the best system is H22:IDTT-ICIN, with an efficiency of 10.12%. The efficiency of the original H22:IDT-ICIN system is 7.6%, which shows that the photoelectric performance of the IDTT unit has been greatly improved compared with the original IDT unit. few.

Xu Qiu immediately realized that IDTT-ICIN would be a very important standard sample system, so he named IDTT-ICIN ITIC. For the standard sample system, it is better to have a simpler name, such as PCE10, P3HT, PCE11, PCBM, etc. . A simple name is easy to be remembered by others and recognized by peers.

In addition, the ITIC system is different from the 3D-PDI system. The optimal device processing conditions for this ADA molecule do not require post-annealing treatment or solvent additives. It only needs normal spraying, which is very simple and very " clean".

Moreover, the performance of devices prepared by normal spin coating is about 2% lower than that of devices prepared by spray coating, only 8.33%. If other people do not know the technique of spray coating, it will be more difficult to reproduce this result.

Second, based on the structures of IDT-ICIN-4F/4Cl/DM, compared with IDT-ICIN, -4F and -DM systems, the performance has been improved, and the range is not small, from 6.22% to 8.92% and 8.06 respectively. %, while the -4Cl system decreased slightly to 5.77%.

Third, Xuemei's H3x system, that is, after introducing fluorine atoms into the BDT unit, the performance of the device did not improve, but slightly decreased.

According to the existing literature, from a statistical point of view, the probability of performance improvement by introducing fluorine atoms into BDT is about 20%. Of course, the idea is that although the probability is not high, it is worth trying. big deal.

Because even if it is a material that hits the street, combined with ITIC, the device performance is 8.72%, and there is no problem with ACSAMI in the end.

Fourth, the FN-ICIN system of the post-doctorate sister, referred to as FNIC by Xu Qiu, has an efficiency of up to 9.64%. The optimal matching donor is the narrow bandgap PCE10, not the wide bandgap H22 series.

Xu Qiu deduced that the length of the molecular conjugation may be extended, and the light absorption range will move to the near-infrared direction, so as to form complementary light absorption with narrow band gap materials.

He conveniently asked the simulation experimenter to measure a light absorption spectrum, which was verified. The conjugate lengths of IDT-ICIN, ITIC, and FNIC are 5, 7, and 9, respectively, and the light absorption ranges are roughly 550-750, 600-800, 650-850, that is, every time the conjugation length increases by 2, the light absorption is red-shifted by about 50 nanometers.

In addition to drawing four conclusions, Xu Qiu also came up with the next optimization direction by the way.

The first priority is to synthesize IDTT-ICIN-4F, IDTT-ICIN-DM and FN-ICIN-4F, which he referred to as IT-4F, IT-DM and FN-4F respectively.

The second priority is to synthesize monofluoro and monomethyl substituted ICIN-F, ICIN-M units, and the synthesis of monochloro substituted structures is of little significance. This can not only publish articles, but also clarify the influence of the number of introduced heteroatoms and methyl groups on device performance. In many cases, although the changing trend can be roughly guessed, it is only a guess if the material is not synthesized and tested.

The third priority, side chain modification, uses thiophene side chains and side chains connected to the hexyl group at the meta position of the benzene ring to replace the side chains connected to the hexyl group at the para position of the benzene ring in the ITIC system.

It was different from the time when we were sprinting for efficiency. At that time, it was a new structure, so many standards were met, and it was almost a grade of articles. For example, 8% was the second district, and 10% was the first district.

Now for these new jobs, it is equivalent to belonging to a similar structure. As long as the efficiency of the device is kept above a certain value, the efficiency breakthrough may not be achieved every time. As long as the story is told well, good articles can also be published. For example, top-level articles like AM.

Of course, if you want to publish better articles, such as the main journal of "Nature" and major sub-journals, you still need to improve efficiency, or at least break the existing efficiency record.