Self-Assembly of Perylene Imide Molecules into 1D Nanostructures: Methods, Morphologies, and Applications Shuai Chen, †,‡ Paul Slattum, ∥ Chuanyi Wang,* ,† and Ling Zang* ,§ † Laboratory of Environmental Sciences and Technology, Xinjiang Technical Institute of Physics & Chemistry, Key Laboratory of Functional Materials and Devices for Special Environments, Chinese Academy of Sciences, Urumqi 830011, China ‡ The Graduate School of Chinese Academy of Science, Beijing 100049, China § Nano Institute of Utah and Department of Materials Science and Engineering, University of Utah, Salt Lake City, Utah 84112, United States ∥ Vaporsens Inc., Salt Lake City, Utah 84112, United States CONTENTS 1. Introduction 11967 2. Molecular Synthesis 11968 3. Self-Assembly 11970 3.1. Solvent-Phase Interfacial Self-Assembly 11970 3.1.1. Bulk Bisolvent Phase-Transfer Self-As- sembly 11971 3.1.2. Solvent-Vapor Diffusion Self-Assembly 11972 3.1.3. In Situ Self-Assembly on Substrate Surface 11973 3.2. Self-Assembly of Bay-Substituted PDIs 11974 3.3. pH-Triggered Self-Assembly in Aqueous Solution 11977 3.4. Aqueous Self-Assembly of Ionic PDIs 11977 3.5. Chemical Reaction-Mediated Self-Assembly of Unsubstituted PIs 11978 3.6. Self-Assembly of Oligomers 11978 3.7. Interfacial Engineering of Nanofibril Hetero- junctions 11978 3.8. Self-Assembly and Chiral/Helical Nanostruc- tures 11979 4. Applications 11982 4.1. OSCs 11982 4.2. OFETs 11985 4.3. Linear Optoelectronics 11986 4.4. Chemical Vapor Sensing 11988 4.5. Photocatalysis 11989 4.6. Thermoelectricity 11990 5. Analogues of PIs 11991 6. Conclusions and Outlook 11992 Author Information 11993 Corresponding Authors 11993 Notes 11993 Biographies 11993 Acknowledgments 11993 References 11993 1. INTRODUCTION Supramolecular self-assembly, since its beginning in the later 1980s, has attracted increasing attention as a breakthrough methodology in the fields of nanoscience and nanotechnol- ogy. 1,2 In contrast to “top-down” approaches such as the templating method, electron-spinning, and nanolithography, and other “bottom-up” approaches such as physical vapor deposition, molecular self-assembly is usually conducted in the solution phase and is governed by weak noncovalent interactions. 2−4 In the last decades, great efforts have been directed to the solution-processable self-assembly of π- conjugated small molecules, oligomers, or polymers into shape-defined nanostructures, offering an attractive pathway to construct well-organized functional nanomaterials, which help bridge the gap between natural and artificial systems. 3−8 These nanostructures and corresponding morphologies are cooperatively controlled by noncovalent forces including H- bonding, dipole−dipole attraction, π−π stacking, van der Waals force, hydrophobic effect, electrostatic interaction, and metal− ligand coordination. In most cases, intermolecular intrinsic π−π stacking and highly directional H-bonding have been demonstrated as the major driving forces, which often act in cooperation with one or more other noncovalent interac- tions. 4,9 Nevertheless, these interactions are highly dependent on the molecular structures and are sensitive to external environmental parameters such as solvent, temperature, concentration, and fabrication process. 2,4,6 For self-assembly on a substrate, the surface characteristics like polarity play a critical role in precisely controlling the morphology of molecular assemblies thus produced. 6 Among a large number of functional nanostructures with dimensionality distinguished between zero-dimensional (0D), one-dimensional (1D), two-dimensional (2D), and three- Received: May 26, 2015 Published: October 6, 2015 Review pubs.acs.org/CR © 2015 American Chemical Society 11967 DOI: 10.1021/acs.chemrev.5b00312 Chem. Rev. 2015, 115, 11967−11998