The invention discloses a preparation method of a water-soluble
small molecule pyridinium photoelectric material. The method comprises the following steps of: adding
pyridine and
acetonitrile into a reaction container, heating and stirring the materials, adding a bromomethyl or chloromethylated aromatic
heterocyclic compound to the reaction container, cooling the materials to
room temperature after the reaction is finished, and removing the
solvent under a pressure reduced condition, thus obtaining a coarse product; dissolving the coarse product through
methanol, precipitating and filtering the dissolved product for multiple times, and performing
vacuum drying on the product to obtain the final product; or dissolving the coarse product through
methanol, adding a
sodium salt solution containing an anion group to the product, stirring the solution and the product for two days, removing the
solvent under a pressure reduced condition, washing and
drying the mixture for multiple times, and performing
vacuum drying on the dried mixture to obtain the final product. The water-soluble
small molecule pyridinium photoelectric material is determinate in structure and molecular weight and is easily purified, avoids the problem that the batch of a
polymer interface material is instable, and has the advantages of high water
solubility, film-forming property, film morphology stability, high eletrophilicity, deep lowest unoccupied
molecular orbital (LUMO)
energy level and low
electron injection / extracting energy barrier.