Charge Transport Properties of Spirofluorene-Based Hole Transport Materials

Abstract

Abstract: Spirofluorene-based hole transport materials have attracted much attention because of their excellent photoelectric properties. In order to explore the charge transport mechanism, the electronic structure, recombination energy and electron coupling of three spirofluorene-based small molecular hole transport materials were studied by density functional theory. Combined with Marcus charge transfer theory, the carrier mobility of all small molecules is accurately calculated and compared with the experimental data. The results show that the hole mobilities of X60 and HT2 molecules are in good agreement with the experimental data, which is in the same order of magnitude, indicating that the theoretical model is feasible to accurately calculate the hole mobility of molecules. In addition, the hole mobility of ST2 is 1.82×10^-4 cm²·V^-1·s^-1, and it displays good stability, which indicates that the modification of heteroatoms in spiro-rings can further improve the performance of hole transport materials. This work provides an important strategy for the development of efficient hole transport materials.

Key words: density functional theory, charge transfer theory, hole transport material, spirofluorene-based hole transport materials, charge transfer

CLC Number:

TB34
TM914.4

HU Weixia, YANG Jixin, HUANG Kai, HE Rongxing. Charge Transport Properties of Spirofluorene-Based Hole Transport Materials[J]. JOURNAL OF SYNTHETIC CRYSTALS, 2021, 50(11): 2138-2143.

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