Its good wettability is very conducive to the preparation of large area devices. In addition, this kind of material can also be used in organic polymer solar cells, with good versatility, and has been applied for Chinese invention patents.

This work innovatively introduces cyanophosphonic acid units, develops biparental small molecule hole transport materials, and constructs ordered, ultra-thin, surface super-infiltrating layers through dynamic self-assembly, which perfectly solves the two major problems of carrier transport and interface defect control in device applications.

As an important class of organic semiconductor materials, organic hole transport materials have achieved large-scale commercial applications in the fields of electrostatic copying, laser printing and organic light-emitting diodes,

and also play an important role in new photovoltaic technologies (such as dye-sensitized solar cells, organic photovoltaic cells and perovskite solar cells). However, organic hole transport materials still face many problems in the application of optoelectronic devices, the most prominent problem is that their low mobility characteristics limit the charge transport performance.

In order to solve the charge transport bottleneck problem of low mobility materials, the field mainly introduces "chemical doping" to improve the film conductivity, but the process is complicated, difficult to prepare,

poor reproducibility, and not conducive to the long-term stability of the device. After long-term research accumulation and a lot of experimental exploration, the research team innovatively proposed the anchoring self-assembly strategy, which effectively solved the two major problems of carrier transport and interface defect control.

The main innovative achievements of the paper include: dynamic anchoring self-assembly, constructing ordered ultra-thin films to break through the bottleneck of hole transport; Biparental design to achieve surface superwetting and interface defect control;

A "double layer" film structure was constructed on a transparent conductive substrate indium tin oxide (ITO) by dynamic anchoring and self-assembly using the biparental small molecule hole transport material. Solve carrier transport and interface defects, breaking the trans-perovskite solar cell certification efficiency record.

As an important class of organic semiconductor materials, organic hole transport materials have been applied commercially on a large scale in the fields of electrostatic copying, laser printing and organic light-emitting diodes,

and also play an important role in new photovoltaic technologies such as dye-sensitized solar cells, organic photovoltaic cells and perovskite solar cells. However, in the application of optoelectronic devices, organic hole transport materials still face many problems, the most prominent one is that their low mobility characteristics limit the charge transport performance.

This work innovatively introduces cyanophosphonic acid units, develops biparental small molecule hole transport materials, and constructs ordered, ultra-thin and surface ultra-infiltrated layers through dynamic self-assembly, which solves the two major problems of carrier transport and interface defect control in device applications with one stone.

It is worth noting that the team also broke the trans-perovskite solar cell certification efficiency record. In addition, the good wettability of the new organic hole transport material is conducive to the preparation of large-area devices.

This kind of material is not only suitable for perovskite batteries, but also can be used in organic polymer solar cells, with good versatility, and has been applied for Chinese invention patent.

In order to solve the charge transport bottleneck problem of low mobility materials, the field mainly introduces "chemical doping" to improve the film conductivity, but the process is complicated,

difficult to prepare, poor reproducibility, and not conducive to the long-term stability of the device. After long-term research accumulation and a lot of experimental exploration,

the research team innovatively proposed the anchoring self-assembly strategy to effectively solve the two major problems of carrier transport and interface defect control. Major innovations include the construction of ordered ultra-thin films with dynamic anchoring self-assembly to break through the bottleneck of hole transport; The biparental design achieves surface superwetting and interface defect control.

Using this biparental small molecule hole transport material, the team constructed a "double-layer" film structure on a transparent conductive substrate indium tin oxide (ITO) by dynamically anchoring self-assembly,

namely an "anchored self-assembled ordered monolayer" and an "unanchored disordered overlay". The self-assembled ordered monolayer with chemical anchoring can be firmly attached to the ITO surface to ensure efficient hole selection and transport,

while the disordered overlay without anchoring has super-infiltrating characteristics due to the molecular amphibiality and easy dissolution characteristics, which is not only conducive to the uniform preparation of large upper layer films, but also can effectively reduce the defect concentration at the interlayer interface.

The team also solved the problems of carrier transport and interface defects, breaking the certified efficiency record of trans-perovskite solar cells. The novel small molecule hole transport materials developed by the researchers have many advantages,

such as anchoring, easy dissolution, easy processing, and super-wetting. The certification efficiency of the trans-structure perovskite solar cell prepared based on the new organic hole transport material reached 25.39% in the third party, which is the highest certification efficiency of this type of solar cell at present.

Zhang Shuo and Ye Fangyuan, PhD students from East China University of Science and Technology, Wang Xiaoyu, PhD students from Jilin University, and Chen Rui, PhD student from Huazhong University of Science and Technology,

are co-first authors of the paper. Professors Wu Yongzhen and Zhu Weihong from East China University of Science and Technology, Dr. Martin Stolterfoht from Potsdam University, Professor Zhang Lijun from Jilin University,

and Professor Chen Wei from Huazhong University of Science and Technology are co-corresponding authors of the paper. The research work was carefully supervised by Academician Tian He and Professor Han Liyuan,

with strong support from Professor Ning Zhijun of Shanghai University of Science and Technology, Researcher Lin Yuze of the Institute of Chemistry of the Chinese Academy of Sciences, and Assistant Professor Wang Yanbo of Shanghai Jiao Tong University in material characterization.