The invention relates to the technical field of solar cells, in particular to a self-
assembly monomolecular material based on a meta-position dicarbazole substitution structure and application of the self-
assembly monomolecular material. In the monomolecular material, two
carbazole derivatives are connected to two meta-positions of a phosphonic
acid group; the meta-position disubstituted structure can restrain self-aggregation in the self-
assembly process, a more compact and uniform film is formed, and high-quality growth of an upper-layer
solar cell material is facilitated; due to the meta-position disubstituted structure,
carbazole large rings on the two sides of a single molecule are exposed in a manner that the front surfaces face upwards, and large-area contact can be formed between the
carbazole large rings and
perovskite growing on the carbazole large rings; the side surface of a carbazole ring of the para-position monocarbazole substituted structure is upward, so that the contact area between the para-position monocarbazole substituted structure and an upper
solar cell material is small; the disubstituted structure has larger
dipole moment,
energy level matching is better,
conductivity is higher, and efficient extraction of holes can be promoted; and by tightly contacting with an upper-layer
solar cell material, the defects of a buried interface can be passivated, non-radiative recombination is reduced, and the efficiency and the stability of the solar
cell are improved.