Temperature-enhanced solvent vapor annealing of a C3 symmetric hexa-peri-hexabenzocoronene: controlling the self-assembly from nano- to macroscale.
Temperature-enhanced solvent vapor annealing (TESVA) is used to self-assemble functionalized polycyclic aromatic hydrocarbon molecules into ordered macroscopic layers and crystals on solid surfaces. A novel C3 symmetric hexa-peri-hexabenzocoronene functionalized with alternating hydrophilic and hydrophobic side chains is used as a model system since its multivalent character can be expected to offer unique self-assembly properties and behavior in different solvents. TESVA promotes the molecule's long-range mobility, as proven by their diffusion on a Si/SiO(x) surface on a scale of hundreds of micrometers. This leads to self-assembly into large, ordered crystals featuring an edge-on columnar type of arrangement, which differs from the morphologies obtained using conventional solution-processing methods such as spin-coating or drop-casting. The temperature modulation in the TESVA makes it possible to achieve an additional control over the role of hydrodynamic forces in the self-assembly at surfaces, leading to a macroscopic self-healing within the adsorbed film notably improved as compared to conventional solvent vapor annealing. This surface re-organization can be monitored in real time by optical and atomic force microscopy.
Treossi
Emanuele
E
Istituto per la Sintesi Organica e la Fotoreattività, Consiglio Nazionale delle Ricerche, via Gobetti 101, 40129 Bologna, Italy.
Liscio
Andrea
A
Feng
Xinliang
X
Palermo
Vincenzo
V
Müllen
Klaus
K
Samorì
Paolo
P
D000327:Adsorption; D018625:Microscopy, Atomic Force; D049329:Nanostructures / Q000737:chemistry*; D011083:Polycyclic Compounds / Q000737:chemistry*; D012825:Silicon / Q000737:chemistry; D012997:Solvents / Q000737:chemistry*; D013499:Surface Properties; D013696:Temperature; D013816:Thermodynamics
D011083:Polycyclic Compounds; D012997:Solvents; C507240:hexa-peri-hexabenzocoronene; D012825:Silicon