Supramolecular interactions were studied in two planar model systems, 1,5- and 2,6-dibromoanthraquinones, prepared on Au(111) using scanning tunneling microscopy. In both systems, we found rigid triangular structures that consisted of simultaneous halogen bonds and hydrogen bonds, as reported in protein−ligand complexes. We proposed molecular models that were well reproduced by first-principle studies and could be explained by halogen and hydrogen bonds. The distances, angles, and, strengths of the intermolecular bonds were measured in the observed structures, and showed good agreement with existing bulk data.

Interchain interactions in arrays of metal–organic hybrid chains were studied using scanning tunneling microscopy and ab initio calculations. The array of hybrid chains having a Ag–anthryl biradical were self-assembled by catalytic scission of Br–C bonds in 9,10-dibromoanthracene on Ag(111). An atomic model for the observed chain structures was proposed. Ag atoms in chains were alternatingly located at hollow sites, making slightly zigzaging structures. Between the hybrid chains, Br atoms located at hollow sites to form Br···H intermolecular bonds. Anthryl biradicals had two different apparent heights; this was explained by considering Br···H intermolecular bonds and intrachain steric repulsion. When a hybrid chain was laterally moved by manipulation techniques, Br adsorbates moved together with the chain, implying that they are stabilized by Br···H intermolecular bonds.

The electronic structures of self-assembled hybrid chains comprising Ag atoms and organic molecules were studied using scanning tunneling microscopy (STM) and spectroscopy (STS) in parallel with density functional theory (DFT). Hybrid chains were prepared by catalytic breaking of Br-C bonds in 4,4″-dibromo-p-terphenyl molecules, followed by spontaneous formation of Ag-C bonds on Ag(111). An atomic model was proposed for the observed hybrid chain structures. Four electronic states were resolved using STS measurements, and strong energy dependence was observed in STM images. These results were explained using first-principles calculations based on DFT.

Intermolecular structures of porous two-dimensional supramolecular networks are studied using scanning tunnelling microscopy combined with density functional theory calculations. The local configurations of halogen bonds in polymorphic porous supramolecular networks are directly visualized in support of previous bulk crystal studies.

The long-term cycling of anode-free Li-metal cells (i.e., cells where the negative electrode is in situ formed by electrodeposition on an electronically conductive matrix of lithium sourced from the positive electrode) using a liquid electrolyte is affected by the formation of an inhomogeneous solid electrolyte interphase (SEI) on the current collector and irregular Li deposition. To circumvent these issues, we report an atomically defective carbon current collector where multivacancy defects induce homogeneous SEI formation on the current collector and uniform Li nucleation and growth to obtain a dense Li morphology. Via simulations and experimental measurements and analyses, we demonstrate the beneficial effect of electron deficiency on the Li hosting behavior of the carbon current collector. Furthermore, we report the results of testing anode-free coin cells comprising a multivacancy defective carbon current collector, a LixNi0.8Co0.1Mn0.1-based cathode and a nonaqueous Li-containing electrolyte solution. These cells retain 90% of their initial capacity for over 50 cycles under lean electrolyte conditions.