In situ Electrochemical-Triggered Dopamine Enzymatic Polymerization for Self-Revealing and Self-Erasing Information Storage.

Hydrogels are emerging as revolutionary information storage media due to their unprecedented responsive and reprogrammable properties. To address the challenge of dynamic information storage without the necessity for external stimuli, electrical writing techniques are adopted for creating dopamine-modified chitosan pattern hydrogel with both self-revealing and self-erasing capabilities, which is realized by modulation the oxidation rate of dopamine spatiotemporally. Specifically, the in situ electrochemical reaction on the surface of electrode initiates the cascade enzymatic canalization of dopamine confining the fast reaction within the writing area, which leads to quick information self-revealing. However, the subsequent air oxidation of dopamine in the unwritten area generally results in self-erasing information. This work pioneers the use of electrical methods to produce hydrogen peroxide on hydrogels, enabling rapid oxidation of dopamine and effective information storage within the hydrogel, which opens new avenues for patterned hydrogels with information storage capabilities.