X. Zhang, Y. Hu, C. R. Lien-Medrano, J. Li, J. Shi, X. Qin, Z. Liao, Y. Wang, Z. Wang, J. Li, J. Chen, G. Zhang, J. V. Barth, T. Frauenheim, W. Auwärter, A. Narita, K. Müllen, C. Palma

J. Am. Chem. Soc.  145, 8757–8763 (2023).

Graphene nanoribbon heterostructures and heterojunctions have attracted interest as next-generation molecular diodes with atomic precision. Their mass production via solution methods and prototypical device integration remains to be explored. Here, the bottom-up solution synthesis and characterization of liquid-phase-processable graphene nanoribbon heterostructures (GNRHs) are demonstrated. Joint photoresponsivity measurements and simulations provide evidence of the structurally defined heterostructure motif acting as a type-I heterojunction. Real-time, time-dependent density functional tight-binding simulations further reveal that the photocurrent polarity can be tuned at different excitation wavelengths. Our results introduce liquid-phase-processable, self-assembled heterojunctions for the development of nanoscale diode circuitry and adaptive hardware.