Temporally programmed switching of functional states in polyaniline film

Polyaniline films are under extensive consideration for applications in sensors, memory devices, displays, biomedicals, etc., owing to their unique optical and electronic functional states that are switchable in response to external stimuli. The application arena of these materials could be enhanced by creating active, adaptive, and autonomous systems with preprogramable spatiotemporal control over the functional states. Here, we present a simple approach to achieve autonomous temporal regulation of polyaniline films’ optical and electrical states by integrating enzyme-catalyzed biochemical reaction. The enzymatic reaction produces a feedback-induced transient pH profile, and correspondingly, the functional states of polyaniline films give rise to a similar switching profile, whose lifetime could be preprogrammed via enzyme concentration. This autonomous, temporally regulated polymer film system represents an advancement to the existing switchable materials that operate at equilibrium.