Nucleation-Governed Reversible Self-Assembly of an Organic Semiconductor at Surfaces: Long-Range Mass Transport Forming Giant Functional Fibers

摘要: The use of solvent-vapor annealing (SVA) to form millimeter-long crystalline fibers, having a sub-micrometer cross section, on various solid substrates is described. Thin films perylene-bis(dicarboximide) (PDI) derivative, with branched alkyl chains, prepared from solution exhibit hundreds nanometer-sized PDI needles. Upon exposure the vapors chosen solvent, tetrahydrofuran (THF), needles re-organize into long fibers that have remarkably high aspect ratio, exceeding 10 3 . Time-and space-resolved mapping optical microscopy allows self-assembly mechanism be unravelled; found nucleation-governed growth, which complies an Avrami-type mechanism. SVA lead featuring i) long-range order (up millimeter scale), ii) reversible characteristics, as demonstrated through series assembly and disassembly steps, obtained by cycling between THF CHCl solvents, iii) mass transport because molecular motion occur at least over micrometers. Such detailed understanding growth process fundamental control formation self-assembled architectures pre-programmed structures physical properties. versatility approach proved its successful application using different solvents. Kelvin probe force reveals highly regular thermodynamically stable greater electron-accepting character than smaller drop-cast films. giant can grown in situ gap microscopic electrodes supported SiO x , paving way towards micro- nanoelectronics.