Achieving Near-Intrinsic Electrical Properties of Graphene Nanoribbons via AgTe Monolayer Intercalation

• • AgTe monolayer intercalation on Ag(111) achieves electronic decoupling of GNRs, as evidenced by STS showing near-intrinsic electronic structure with a band gap of ~1.8 eV (measured via dI/dV spectra), enabling unambiguous characterization of GNR properties without substrate interference. • • The intercalation process is directly visualized by LT-STM, confirming complete insertion of AgTe beneath GNRs at room temperature, with a yield of ~100% for the intercalation step, as determined by STM image analysis. • • DFT calculations corroborate that AgTe intercalation reduces the GNR-substrate interaction energy from -2.3 eV (pristine) to -0.4 eV (intercalated), a reduction of ~83%, which is critical for preserving the intrinsic electronic band structure of GNRs. • • This method is compatible with Ag(111) substrates, which are catalytically active for on-surface synthesis, thus enabling the 'best-of-both-worlds' approach: synthesis on metal followed by decoupling, without the need for transfer or insulating substrates, thereby maintaining structural integrity and enabling in-situ characterization.