Chapter 256: "Target" not found
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I Have a Research Support System
- Plump leeks
- 2066 characters
- 2021-02-02 04:21:18
Next, it was Chen Wanqing's turn to report.
At the group meeting last week, she and Sun Wo were still "difficult brothers", now they are completely different.
Because she got the device data that Xu Qiu helped her do on Friday, the highest efficiency of the ICIN system has reached 3.81%, which is close to 4%.
With the data in hand, the whole person is instantly hardened.
In addition, she also added basic light absorption spectroscopy, fluorescence spectroscopy and other tests, and the number of PPT pages of the group meeting directly reached as many as eight pages, and there was nothing to say about the workload.
Wei Xingsi was also a little surprised. Chen Wanqing had been looking forward to the future at the group meeting for more than a month. He was laying out experimental plans, and there was almost no progress. He still stayed at 1% photoelectric conversion efficiency for the device performance of Chen Wanqing’s ADA system. Unexpectedly, it was suddenly close to 4%.
Seeing that she didn't play the outlook part this time, Wei Xingsi asked curiously: "What are your plans next?"
Chen Wanqing spoke confidently: "I am going to complete the basic characterization of this material first. After all, it is a new structure, and the efficiency is not low, and there may be room for optimization. Moreover, I noticed that IDT-ICIN The main light absorption range of this material is between 500-800 nanometers. It has a great overlap with the PCE10 donor material. I am considering whether to try another donor..."
"Change the donor material," Wei Xingsi suddenly interrupted, "Xu Qiu, what do you think?"
"I think Chen Wanqing's idea is feasible. You can try other wide band gap polymer donor materials." Xu Qiu replied.
On Friday, he led the senior sister to measure the light absorption spectrum first, the purpose is to let her notice the problem of the overlap between the light absorption range of the donor and the receptor, but she did not expect her to get resuscitation very quickly.
Wei Xingsi considered for a while, nodded and said: "Okay, but wide bandgap polymer donor materials, after all, do not fit the traditional fullerene system. There are not many types of them. Please check several optoelectronic companies to see if there are any. If there is no commercial channel, if it doesn’t work, buy the monomer and synthesize it yourself.
Xu Qiu didn't answer the conversation. He also felt that from a long-term perspective, self-synthesis was definitely the best choice, but now the organic trio has their own division of labor, and they can't make a move, so they can't compete with Wu Feifei.
Chen Wanqing said suddenly: "I remember the polymer donor sample sent by the photoelectric company in Shenzhen before, there seems to be a wide band gap FTAZ material."
After finishing, she looked at Xu Qiu as if asking, Xu Qiu pretended to think about it for a few seconds, and then echoed: "It should be there. I will look for it later."
"It would be best if there are ready-made materials," Wei Xingsi said with a smile: "Of course, the main energy should be placed on the PCE10 system, to see if the photoelectric performance can be improved, the efficiency is best to achieve 5 % Above, so you can try to hit it."
Xu Qiu gave a "um", nodding on the surface, and silently complaining in his heart, "It is not easy for the PCE10 system to break 5%, but the PTAZ system has now exceeded 5%, reaching 5.48%, and there is even a chance to break 6%. , To break the current world record of the ADA system. ’
However, he can also understand Teacher Wei's thoughts.
For Mr. Wei, PTAZ is an unfamiliar system. Although it is complementary to IDT-ICIN's light absorption, theoretically the upper limit of the photoelectric performance is higher, but in reality, it is only after the photovoltaic device is prepared and tested. You know, and the PCE10 system is a system with proven performance.
After all, the light absorption performance of the effective layer is not the only factor that affects the optoelectronic performance of the device, but compared to the energy level structure, blending morphology, and charge transport, which are more "virtual", more microscopic concepts, light absorption performance comparison "Real", relatively intuitive, can be obtained by directly testing the light absorption spectrum of the material.
In fact, the light absorption performance mainly determines the upper limit of the photoelectric conversion efficiency of the device. According to the Shockley Quayser efficiency limit theory, the single junction solar cell of the inorganic system, when the band gap of the photoelectric material is about 1.2-1.4 eV , The photoelectric conversion efficiency is the highest, the upper limit is about 33%. At this time, the battery device can absorb light with a wavelength of less than 1000 nanometers, covering most of the solar spectrum.
Due to the exciton absorption characteristics of organic photoelectric materials, the light absorption performance of the material varies with the wavelength of light as a peak curve, and there is a main light absorption range.
For example, an organic polymer donor PCE10 material with a band gap of about 1.6 electron volts, the main light absorption range is about 550-750 nanometers, and the absorption capacity for light less than 550 nanometers is relatively weak, so it is blue-violet .
For another example, the non-fullerene acceptor PDI material has a band gap of about 2.1 electron volts, and the main light absorption range is about 400-600 nanometers. It hardly absorbs red-orange light, so it is red-orange.
When other factors are not considered, for 1.6 eV optoelectronic materials, if it is an inorganic material, the main light absorption range is less than 750 nanometers, and the theoretical limit of efficiency is about 30%;
If it is an organic material, if it is a system with complementary light absorption, for example, the main light absorption range is 300-750 nanometers, the upper limit of efficiency may drop slightly and remain at about 28%;
But if the light absorption is not complementary, the main light absorption range is 500-750 nanometers, the upper limit of efficiency will further drop to 25%.
Of course, the% here is just an example. If different theoretical models are applied, the calculated results are also different.
Anyway, for non-fullerene system devices whose current efficiency is only 4% or 5%, the theoretical efficiency of 20+% is still very far away.
The main factors that drag down the efficiency are the relatively "virtual" and microscopic factors such as energy level structure, blending morphology, and charge transport.
And these factors are not difficult to quantify.
This is also the reason why Xu Qiu and the others will make a wave of devices to test the water every time they synthesize a material. It is also the reason why Teacher Wei prefers to study the PCE10 system first.
Materials subject, in the final analysis, is a subject of trial and error.
After Chen Wanqing's report was over, Xu Qiu was waiting to get up to take over.
Wei Xingsi raised his hand, interrupted his movement, and said, "Xu Qiu, you don't need to talk about it. You can save it after the group meeting and show me your article again."
"Okay." Xu Qiu nodded in response, feeling a little regretful. The group meeting PPT did it for nothing, but it was relieved to think that he did not spend much time. He just copied and pasted and directly used the few used in the article. Post the picture to the PPT template of the group meeting and it takes less than three minutes to complete.
Speaking of it, Xu Qiu and Han Jiaying's daily dating project this weekend is to find an vacant classroom, sit in a row, and then talk about it.
Up to now, Xu Qiu has completed the reference and supporting information. Only the experimental data obtained can be finished, and the progress of the article by the school girl has advanced by about 10%.
Finally, Han Jiaying reported on the progress of her work: "...Currently, the highest efficiency is 7.5%...Basic characterization is basically completed...The article is about 30% written...Now the third generation 3D-PDI materials are mainly developed..."
Because her 3D-PDI system is similar to Xu Qiu's, Wei Xingsi did not interrupt her questioning when she was speaking.
After speaking, Wei Xingsi first encouraged a few words, and then asked: "How about the third-generation material development of this B4T series?"
"The progress is over halfway, and the product should be available next week." Han Jiaying replied.
"Okay," Wei Xingsi paused, then suddenly looked at Chen Wanqing and asked, "When is the light source test?"
"Next Saturday, from 9 am to 9 pm, I have completed the security audit on Wednesday." Chen Wanqing answered.
"Or the three of you?" Wei Xingsi asked.
Xu Qiu, Chen Wanqing and Han Jiaying looked at each other and said together, "That's right."
Wei Xingsi nodded and continued to order: "Han Jiaying, try to make your third-generation materials before the light source test, otherwise you will have to wait a long time if you miss this time."
"No problem." Han Jiaying nodded.
"But..." Wei Xingsi changed his words: "At present, the main focus is on your current article. Since the publication of that JACS, I have not seen any new articles on the 3D-PDI system. I guess it will be soon. With that, we still have to speed up the progress and get ahead of the others."
"Yeah." Han Jiaying also understands that although her current job, one less AEM, there is a high probability of being able to post AM, but before the article is written, not voted out, and not officially included, there are variables. Didn't the article of Yan Hu's research group just get killed by my senior.
Wei Xingsi took a sip of tea and suddenly smiled and said: "We have raised the efficiency threshold of the 3D-PDI system so high all at once. It will be difficult for others to post good articles."
Xu Qiushen agrees that the efficiency of the first 3D-PDI system is only 4%. If Xu Qiu and the others directly set the efficiency to 7% and 8% in the second and third articles, then others will hold the results of 5% and 6%. , There was a chance to make a strong one-district journal, such as AEM, but now it may only be a weak one or even two-district journals.
For this reason, some research groups will press articles to make the progress of a field show a slow upward trend, such as efficiency 8% and% all the way up ~EbookFREE.me~ instead of jumping directly from 8% to 11%. The former can be filled with four articles, while the latter can only have one.
Although this phenomenon may seem a bit awkward, it can be regarded as an unspoken rule of the industry.
After all, postgraduates help their supervisors to graduate by posting articles. In the future, if they want to continue to do research related, go abroad to study for Ph.D. application, SCI articles are also very important, and for supervisors, the number of SCI articles Quality is also one of the main indicators for evaluating its scientific research capabilities.
Before, Xu Qiu’s PCE11 system was actually a similar operation. He was not a saint. When he was unable to change the rules, it would be a good choice to temporarily integrate the rules.
Wei Xingsi put down his tea cup, and did not rush to announce that the "group meeting is over", but instead looked at his students and planned to find a "target".
Wu Feifei’s review is at the end, and it can be posted in a few days. Because it is the editor of Adv. Sci. The new issue has a high probability of submission;
Xu Qiu, Han Jiaying, and Chen Wanqing will not talk about them, and they have made breakthroughs in the field of non-fullerenes. At present, I don’t want to talk about one area.
It is safe for even Duan Yun and Tian Qing to post an article about weak district one or two.
After all, only Sun Wo has no articles.
But Sun Wo is only an undergraduate, and later he will only come here to study for a master's degree, not a doctoral degree, and he can't push too hard.
After looking around, Wei Xingsi found that he couldn't find the PUSH target...