Gu M.-WPeng H.HChen I.-W.PCHUN-HSIEN CHEN2021-08-032021-08-03202114761122https://www.scopus.com/inward/record.uri?eid=2-s2.0-85099923127&doi=10.1038%2fs41563-020-00876-2&partnerID=40&md5=9489728c75fa265130d26242a9ed5149https://scholars.lib.ntu.edu.tw/handle/123456789/575719Understanding chemical bonding and conductivity at the electrode–molecule interface is key for the operation of single-molecule junctions. Here we apply the d-band theory that describes interfacial interactions between adsorbates and transition metal surfaces to study electron transport across these devices. We realized bimetallic Au electrodes modified with a monoatomic Ag adlayer to connect α,ω-alkanoic acids (HO2C(CH2)nCO2H). The force required to break the molecule–electrode binding and the contact conductance Gn=0 are 1.1 nN and 0.29 G0 (the conductance quantum, 1 G0 = 2e2/h ? 77.5 μS), which makes these junctions, respectively, 1.3–1.8 times stronger and 40–60-fold more conductive than junctions with bare Au or Ag electrodes. A similar performance was found for Au electrodes modified by Cu monolayers. By integrating the Newns–Anderson model with the Hammer–N?rskov d-band model, we explain how the surface d bands strengthen the adsorption and promote interfacial electron transport, which provides an alternative avenue for the optimization of molecular electronic devices. ? 2021, The Author(s), under exclusive licence to Springer Nature Limited.Chemical bonds; Electrodes; Molecules; Transition metals; Conductance quantum; Contact conductance; Electron transport; Interfacial interaction; Molecular electronic device; Molecular junction; Single-molecule junctions; Transition metal surfaces; Electron transport propertiesjournal article10.1038/s41563-020-00876-2335104462-s2.0-85099923127