Time-dependent switching of temperature-sensitive nanofilm processors

[Display omitted] •2D electrochemical nanofilm processors are self-writing smart labels.•Coupling of time indicating nanofilm processors with time-temperature-integrating nanofilm processors. Nanofilm processors are paper-thin self-writing smart labels based on an electrochemical cell. In the presence of a counter electrode, a nanoscale aluminum layer is oxidized laterally and is optically detectable by a sharp boundary between the aluminum and the oxidized aluminum, without the need for an external power supply. Nanofilm processors have different sensory properties. In this article, we describe the basics of temperature-dependent and temperature-independent nanofilm processors. For the first time, we have designed and verified the combination of these functionalities in a series of time–temperature integrators that get activated in fixed time intervals. This is a milestone in the development of a fully functioning time- and temperature-monitoring smart label, termed as a “thermograph”.