Twisted Graphene Nanoribbons for Breakthroughs in Energy Storage, Bioelectronics and Chiroptics

ConspectusTwisted graphene nanoribbons (tw-GNRs), exemplified by helical perylene diimide (hPDI) oligomers and polymers, represent a versatile platform for next-generation organic electronics. Their distinctive architecture features a fused, twisted backbone that simultaneously introduces void space for ion transport while maintaining high electronic conductivity along the graphitic core. This Account details the development of these materials, underpinned by a defect-free polymerization-cyclization synthesis based on perylene tetraester precursors. This robust synthetic route enables the creation of ribbons up to 120 nm long with precise control over molecular length, edge chemistry, and backbone helicity, allowing for a systematic investigation of structure-property relationships.Leveraging this unique combination of properties, we address key challenges in energy storage, bioelectronics, and chiroptics. In the context of energy storage, we discuss how intermediate-length ribbons strike a structural "sweet spot" that balances the trade-off between electrode insolubility and ion permeability, facilitating ultrafast charging kinetics in lithium and magnesium batteries. Furthermore, we demonstrate how introducing cruciform hinges into the backbone creates an amorphous morphology that resolves the critical "conductivity-hydrophilicity-insolubility" trade-off, enabling high-performance aqueous sodium-ion batteries. In bioelectronics, we describe how modifying the ribbon edges with hydrophilic chains enables high performance and ultrastable n-type organic mixed ionic-electronic conductors (OMIECs) capable of high-fidelity neural recording. Finally, we explore the chiroptical properties of these ribbons, explaining how remote chiral side chains can dynamically induce long-range helical order in the backbone. This structural control allows the materials to function as room-temperature spin filters via the chiral-induced spin selectivity (CISS) effect.Collectively, these studies illustrate how precise molecular engineering can unlock new functionalities, ranging from dual ion-electron conduction to spin-selective transport, defining a versatile platform for next-generation organic electronics.