Engineering Temperature‐Switchable Conducting Metal–Phenolic Network Films

ABSTRACT Designing energy‐efficient materials capable of transitioning between insulating and conducting states with ultrahigh ON/OFF ratios is a key challenge in advancing electronic materials. Herein, a class of materials exhibiting temperature‐tunable insulator–metal transitions based on the facile chemistry of metal–phenolic networks (MPNs) is reported. Enhanced π – π stacking in the materials at elevated temperatures triggers a transition from insulating to highly conductive states, as confirmed experimentally and by molecular dynamics simulations. The MPN films (∼10–300 nm thick) exhibit ultrahigh OFF‐state resistance, tunable transition temperatures (354–504 K), ultrafast switching speeds (18 cm 2 ), tunable electrical properties (via ligand and metal choice), and compatibility with diverse electronic devices and circuits. This work offers a pathway to developing low‐cost, customizable material platforms for smart electronics.