Organic N-type Dopants with a Phenyl Tertiary Carbon Structure: Molecular Structure and Doping Properties

作者：Gao, Ran; Wu, Qinggang; Zhang, Jiyun; Cen, Huan; Hai, Jiefeng; Li, Xueming; Zhang, Jinxiao; Lu, Zhenhuan^*

来源：ChemistrySelect, 2022, 7(48): e202204021.

DOI：10.1002/slct.202204021

• conductive materials
• conductivity
• n-doping
• organic dopants
• structure-activity relationship

Doping is an effective method to improve the electrical properties of organic semiconductors or insulators. However, current progress in organic n-doping is limited relative to pdoping. Benzimidazole derivatives are representative organic n-type dopants that have been widely applied, e. g., 1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo [d] imidazole (DMBI); its active unit is the phenyl tertiary carbon structure. Here, we designed and synthesized 11 small organic molecules with different phenyl tertiary carbon structures that were constituted by different heteroatoms (O, S, N) and several tertiary carbons to adjust the n-doping performance. These molecules were then applied to dope polyalkylfluorene-based organic semiconductor PFN to get a composite solid film. After optimization, the electrical conductivities of the prepared films were all enhanced by about three orders of magnitude. After experimentation and analysis, we confirmed that those dopants can effectively transfer their electrons to the host material. In addition, introducing the N atom to tertiary carbon and conjugating heteroatom with an aromatic ring improved its doping efficiency, but strong phase separation performance may result in limits on further heightening of conductivity. Therefore, these results are important for research into organic n-type dopants.

• 单位
  桂林理工大学