A novel fluorescent waterborne polyurethane-based Sm (III) ternary complex improves plant growth in light environments and promotes plant growth

Abstract

Polymeric rare earth complexes have attracted much attention due to their unique luminescence properties and application prospects. However, as an important component of polymeric rare earth complexes, Sm (III) complexes are rarely reported due to the lack of organic ligands matching the energy of Sm (III). Herein, A novel Sm(III) complexes (Sm(MPon)₃APhen) emitting red fluorescence is synthesized by using Sm(III) as the central ion and 1-(4-tert-butylphenyl)-3-(4-methoxyphenyl)-1,3-propanone (MPon) and 5-amino-1,10-phenanroline (APhen) as ligands, respectively. Then, A novel waterborne polyurethane-based complex [Sm(MP)₃AP]_x-WPU with orange-red fluorescence is prepared by modified acetone method using Sm(MPon)₃APhen as the end-blocking agent. Compared with Sm(MPon)₃APhen, the fluorescence emission peak of [Sm(MP)₃AP]_x-WPU is blue-shifted, and the fluorescence intensity is significantly enhanced with the increase of the amount of Sm(MPon)₃APhen. Notably, the strongest fluorescence emission peak of [Sm(MP)₃AP]_x-WPU is located in the red light band with the highest photosynthetic absorption efficiency of plants, which could significantly improve the light environment for plant growth and promote plant growth. More importantly, [Sm(MP)₃AP]_x-WPU is water as a dispersed phase, which is particularly safe and environmentally friendly during storage, transportation and use.