Volume 1, Issue 1, Pages 78-90 (July 2016) Synthesis of Graphene Nanoribbons via the Topochemical Polymerization and Subsequent Aromatization of a Diacetylene Precursor  Robert S. Jordan, Yue Wang, Ryan D. McCurdy, Michael T. Yeung, Kristofer L. Marsh, Saeed I. Khan, Richard B. Kaner, Yves Rubin  Chem  Volume 1, Issue 1, Pages 78-90 (July 2016) DOI: 10.1016/j.chempr.2016.06.010 Copyright © 2016 Elsevier Inc. Terms and Conditions

Chem 2016 1, 78-90DOI: (10.1016/j.chempr.2016.06.010) Copyright © 2016 Elsevier Inc. Terms and Conditions

Figure 1 Solid-State Packing Parameters for Synthesized Diarylbutadiynes (A–C) C1–C4 and C1–C1 distances are displayed in blue and green, respectively, for compounds 1 (A), 2 (B), and 3 (C). (D) Compound 4 displays two repeating C1–C4 distances highlighted in blue and red, and its C1–C1 distances are shown in green and purple. Chem 2016 1, 78-90DOI: (10.1016/j.chempr.2016.06.010) Copyright © 2016 Elsevier Inc. Terms and Conditions

Figure 2 Chemical and Crystallographic Characterization of PDA-1 and GNR-1 (A and B) Raman (A) and UV-vis-NIR (B) spectra of PDA-1 and GNR-1. Pictures in (B) illustrate the color change upon the conversion from PDA-1 (bottom blue film) to GNR-1 (top brownish black film). (C and D) Selected-area electron diffraction (SAED) patterns of PDA-1 (C) and GNR-1 (D). Insets are the TEM images of the areas where diffraction patterns were collected. Chem 2016 1, 78-90DOI: (10.1016/j.chempr.2016.06.010) Copyright © 2016 Elsevier Inc. Terms and Conditions

Figure 3 TEM Characterization of GNR-1 (A and B) TEM images of a bundle of GNRs (A) and two adjacent individual GNRs (B). (C) High-resolution TEM image of a GNR stack shows the characteristic (002) graphene interlayer spacing. Inset is the FFT pattern of the lattice fringes. (D) High-resolution TEM image reveals the well-ordered basal plane of the GNR. The corresponding FFT pattern along the index is shown in the inset. The red dash lines border the edge of the GNR. Chem 2016 1, 78-90DOI: (10.1016/j.chempr.2016.06.010) Copyright © 2016 Elsevier Inc. Terms and Conditions

Figure 4 Patterning and Electrical-Property Characterization (A–C) Optical microscopy images of stars, lines, and UCLA CHEM patterns comprise GNR thin films obtained by selective-area adsorption of PDA followed by solid-state aromatization. (D) Optical microscopy image of a GNR transistor. (E) Transfer characteristics of a GNR transistor at Vsd = 1 V. (F) Drain current (Isd) versus source-drain voltage (Vsd) under different gate-modulation voltages. Chem 2016 1, 78-90DOI: (10.1016/j.chempr.2016.06.010) Copyright © 2016 Elsevier Inc. Terms and Conditions

Scheme 1 Synthetic Approach to GNRs via the Topochemical Polymerization of Polyacetylenes Our approach consists of a three-step process including (1) crystallization of suitable monomers into a solid-state structure suitable for topochemical polymerization, (2) initiation of polymerization using heat or UV light, and (3) subsequent heating to promote cyclization of the polydiacetylene backbone and cyclodehydrogenation to produce GNRs. Chem 2016 1, 78-90DOI: (10.1016/j.chempr.2016.06.010) Copyright © 2016 Elsevier Inc. Terms and Conditions

Scheme 2 Synthesis of Monomer 1 Monomer 1 is prepared in four steps in 60% overall yield from commercially available 6-bromo-2-naphthol. Specific procedures and characterization data for all compounds are provided in the Supplemental Experimental Procedures. Chem 2016 1, 78-90DOI: (10.1016/j.chempr.2016.06.010) Copyright © 2016 Elsevier Inc. Terms and Conditions