Strong near-field scattering enhancement (NFSE) of polyhedral oligomeric silsesquioxanes(POSS) nanoparticles (NPs) aggregates is found through physical simulation. An aggregation of N,N′-di-[3-(isobutyl polyhedral oligomeric silsesquioxanes) propyl] perylene diimide(DPP) which possesses POSS as scatteres experimentally performs strong NFSE, which confirms the physical simulation results. Moreover, coherent random laser is triggered from the DPP aggregates in carbon disulfide. It is the NFSE of POSS NPs connected to both ends of DPP through covalent bonds and the NFSE of their aggregation thanks to DPP’s aggregation that is responsible for the coherent random laser. So, this work develops a method to improve weak scattering of system through construction of molecules, and opens a road to a variety of novel interdisciplinary investigations, involving molecular designing for disordered photonics.
A novel water-soluble luminescent complex consisting of Eu(ally-dbm)3-2Tppo and poly(N-isopropyl acrylamide)(PNIPAM)is synthesized through a series of chemical reactions.The structure of the complex is characterized by TGA,GPC,HNMR,and the thermal-responsive uorescence of the complex in aqueous solution is investigated.It is found that PNIPAM collapse above the lower critical solution temperature causes the coordination bond breaking,leading to weakening of the uorescence from Eu3+and enhancing of the uorescence from the ligands.When temperature decreases,the uorescence from Eu3+is found to boost up and the uorescence from ligands weakens accordingly.It is deduced from this phenomenon that the ligands recoordinate with europium ions again along with the temperature decreasing,which is further confirmed by IR measurements.This thermal-responsive uorescence is of reversibility,which can be used as molecular probes for biological imaging and collapse studying of PNIPAM.
