@article {48087,
	title = {Instabilities as the origin of large-area self-assembled and aligned organic semiconductor nanocrystals},
	journal = {ACS Applied Electronic Materials},
	volume = {4},
	year = {2022},
	month = {APR},
	pages = {1815-1822},
	type = {Article},
	abstract = {<p>
	Aligned nanocrystals of organic semiconductors (OSCs) are highly desirable for electronic devices and biomedical and photonic applications. Solution-based wet processing routes have the potential to produce aligned nanocrystals over large areas in small time frames. Herein, we demonstrate that by optimizing the hydrodynamic evaporative processes, controlled long-range crystalline assemblies of OSCs can be achieved (longest nanocrystal similar to 3 mm) purely through physical processes: namely, from fingering instabilities. Self-assembly is achieved here without strong noncovalent interactions such as hydrogen-bonding interactions. Experimentally our approach involves just placing a drop of a solution on an inclined substrate. Nanocrystals with widths of 300-800 nm and lengths of millimeters (length/width aspect ratios \&gt;10(5)) are formed in less than 2-8 s. A hydrazine chemiresistive sensor based on the aligned crystalline patterns show unprecedented responsivity (similar to 10(-6)), 2 orders greater than those of stick-slip patterns. Finally, experimental parameters that need optimization to achieve nanocrystal patterns are investigated in detail and pointers to fabricate such OSC nanocrystals are provided.</p>
},
	keywords = {aligned fibers, diketopyrrolopyrrole, fingering instability, nanocrystal arrays, naphthalenediimide, organic semiconductors},
	doi = {10.1021/acsaelm.2c00061},
	author = {Venugopalan, Vijay and Jain, Bhanprakash and Mahale, Rajashree Y. and Subramani, Kumar and Krishnamoorthy, Kothandam}
}
