The operation of the multitude of electrical, electronic and energy storage devices that underpin modern civilization is universally based on the interactions between electrical bias and matter. Multiple examples in energy technologies include electrochemical reactions in fuel cells, photoelectrochemical cells and batteries. The need for technology to replace Complementary Metal–Oxide–Semiconductor (CMOS) devices has stimulated the search for alternative data-storage and information-processing mechanisms, ranging from spin–electron coupling in Magnetic Random Access Memory (MRAM) devices  to electron–lattice coupling in ferroelectric RAM and data storage, to electrically triggered phase transitions in Phase Change Memory (PCM) devices. The operation of molecular self-assembled monolayer-based memory devices is often derived from the growth and dissolution of conductive metal filaments, giving rise to the concept of ‘Electrochemical Memory’ (EM). In many of these cases, the operational principle of the device is directly founded on a bias-induced phase or electrochemical transformation, be it polarization switching in ferroelectrics, amorphization and crystallization in PCM, or reversible electrochemical reactions in EM.