A scene that contains both old and instant events with a clear motion trail is visually intriguing and dynamic, which can convey a sense of change, transition, or evolution. Developing an eco-friendly delay display system offers a powerful tool for fusing old and instant events, which can be used for visualizing motion trails. Herein, we brighten triplet excitons of carbon nanodots (CNDs) and increase their emission yield by a multidimensional confinement strategy, and the CND-based delay display array is demonstrated. The intense confinement effects via multidimensional confinement strategy suppress nonradiative transitions, and 240% enhancement in the phosphorescence efficiency and 260% enhancement in the lifetime of the CNDs are thus realized. Considering their distinctive phosphorescence performances, a delay display array containing a 4 × 4 CND-based delay lighting device is demonstrated, which can provide ultralong phosphorescence over 7 s, and the motion that occurred in different timelines is recorded clearly. This finding will motivate the investigation of phosphorescent CNDs in motion trail recognition.
Keywords: carbon nanodots; delay display; motion trail recognition; multidimensional confinement; phosphorescence.