A cascade chemical reaction is selectively activated through oriented external electric field at the single-molecule scale.

Molecular cutout of defect-containing bilayer graphene was achieved by bottom-up synthesis and showed defect-enhanced luminesce.

Keto-enol tautomerism, describing an equilibrium involving two tautomers with distinctive structures, provides a promising platform for modulating nanoscale charge transport. However, such equilibria are generally dominated by the keto form, while a high isomerization barrier limits the transformation to the enol form, suggesting a considerable challenge to control the tautomerism. Here, we achieve single-molecule control of a keto-enol equilibrium at room temperature by using a strategy that combines redox control and electric field modulation. Based on the control of charge injection in the single-molecule junction, we could access charged potential energy surfaces with opposite thermodynamic driving forces, i.e., exhibiting a preference for the conducting enol form, while the isomerization barrier is also significantly reduced. Thus, we could selectively obtain desired and stable tautomers, which leads to significant modulation of the single-molecule conductance. This work highlights the concept of single-molecule control of chemical reactions on more than one potential energy surface.

The development of mesoporous hydrogen-bonded organic frameworks (HOFs) is critically important for various applications, yet it poses significant challenges. Herein, we present the synthesis and characterization of a robust mesoporous HOF, RP-H200, constructed through the orchestration of π-π stacking and hydrogen bonding interactions in a 2-fold interpenetrated framework. RP-H200 features a unique double-walled structure with a pore size of 3.6 nm, representing the largest pore size among reported HOFs to date. The framework exhibits a high surface area of 2313 m² g^-1, with aromatic surfaces dominating the mesoporous channels. The methane storage performance of RP-H200 reaches a high capacity of 0.31 g g^-1 at 270 K/100 bar and 0.25 g g^-1 at 296 K/100 bar. The combination of large permanent mesoporosity, excellent thermal stability, and high surface area in RP-H200 makes it a promising candidate for clean energy storage and other functions.