Properties Of Several Organic Room Temperature Phosphorescent Small Molecule Materials Containing Phosphorus

Organic room-temperature phosphorescent materials（RTP）have promising applications in the fields of illumination,sensing,bioimaging and anti-counterfeiting due to their unique optical properties such as long excited state lifetime and large Stokes shift,and easy quenched by water and oxygen factors.In recent years,among the many organic room-temperature phosphorescent materials studied,phosphorus-containing organic room-temperature phosphorescent materials have become a research hotspot due to the valence-tunable nature of phosphorus atoms.This thesis combines experimental and theoretical calculations to systematically investigate the room-temperature phosphorescent properties of several types of phosphorus-containing organic small molecule materials,such as benzyltriphenylphosphonium halides,chiral binaphthyl phosphates,and phosphorus heterophosphates,with the following work:（1）The optical properties of benzyltriphenylphosphonium bromide halides were investigated,examining the effects of the type of halogen anion,benzyl substituents on the optical properties.It was found that PBr₂,PBr and PCl were similar in the solution state,all emitting blue fluorescence,and the solid state was the same as the polymer film state,all emitting green fluorescence and transient phosphorescence,with the luminescent properties of PBr being significantly better than those of PBr₂and The luminescence of PBr was significantly better than that of PBr₂ and PCl,indicating that the heavy atom effect of the bromine ion is stronger than that of the chlorine ion,but too many bromine ions in the system can also lead to luminescence quenching（2）The optical properties of the mono-enantiomers S-binaphthyl phosphate（S-BNDHP）and R-binaphthyl phosphate（R-BNDHP）were investigated.It was found that both S-BNDHP and R-BNDHP emitted blue fluorescence in the solution state,and weaker than the solution luminescence in the solid state,but significant phosphorescence emission was observed in the polymer-doped film state.Different polymer matrix doped films,only polyvinyl alcohol（PVA）doped films showed a persistent and long-lasting yellow-green afterglow,with phosphor lifetimes of 0.71 s and 0.73 s for PVA films doped at 1%,respectively,and exhibited a unique circularly polarised room temperature phosphorescence emission.（3）To address the shortcomings of organic room-temperature phosphorescent materials that are afraid of water,a new room-temperature phosphorescent material has been constructed using the reversible hydrolysis and condensation reactions between DOPO and HBPA,where DOPO only emits blue fluorescence,but its water hydrolysis into HBPA emits a bright and long-lasting green phosphorescent afterglow,and HBPA is heated and condensed to lose one part of water to form DOPO,showing a reversible fluorescence-phosphorescence switch.This is a relatively rare phenomenon in the field of room temperature phosphorescence.More importantly,HBPA solids emit phosphorescence stably in humid atmospheres and water,with a phosphorescence lifetime of up to 0.48 s.In addition,PVA-doped films of HBPA（10%doping）have a lifetime of up to 0.55 s.