Koo, Byungjin Swager, Timothy M. Highly Emissive Excimers by 2D Compression of Conjugated Polymers Interactions between π-conjugated polymers are known to create ground-state aggregates, excimers, and exciplexes. With few exceptions, these species exhibit decreased fluorescence quantum yields relative to the isolated polymers in liquid or solid solutions. Herein, we report a method to assemble emissive conjugated polymer excimers and demonstrate their applicability in the detection of selected solvent vapors. Specifically, poly­(phenylene ethynylene)­s (PPEs) with amphiphilic side chains are organized in a Langmuir monolayer at the air–water interface. Compression of the monolayer results in the reversible conversion from a face-on organization of the π-system relative to the water to what appears to be an incline-stack conformation. The incline-stack organization creates a bright yellow emissive excimeric state with increases of 28% in relative fluorescence quantum yields to the face-on monolayer conformation. Multilayers can be transferred onto the glass substrate via a Langmuir–Blodgett method with preservation of the excimer emission. These films are metastable and the fluorescence reverts to a cyan color similar to the spectra obtained in solution and spin-cast films after exposure to selected solvent vapors. This behavior has practical utility as a fluorescence-based indicator for selected volatile organic compounds. cyan color;spin-cast films;Emissive Excimers;excimer emission;emissive excimeric state;solution;2 D Compression;glass substrate;Langmuir monolayer;method;face-on organization;incline-stack conformation;species exhibit;face-on monolayer conformation;ground-state aggregates;Conjugated Polymers Interactions;fluorescence-based indicator;polymer excimers;fluorescence quantum yields;amphiphilic side chains;π- system;PPE;incline-stack organization;monolayer results;vapor 2016-07-08
    https://acs.figshare.com/articles/journal_contribution/Highly_Emissive_Excimers_by_2D_Compression_of_Conjugated_Polymers/3474686
10.1021/acsmacrolett.6b00491.s001