2D Ti3C2Tx MXene-based light-driven actuator with integrated structure for self-powered multi-modal intelligent perception assisted by neural network

Conventional Ti3C2Tx MXene-based actuators, due to their lack of human-like self-perception capability, have hindered soft robots from progressing toward intelligent robot-environment interactions. Strategies to reconcile environmental stimulus-response actuation and self-powered multi-modal intelligent perception remain challenging. Here, we have designed a flexible actuator with a P-N couple structure. Wherein, the Ti3C2Tx MXenechitin nanofibers (MCHF) composite film prepared by vacuum-assisted self-assembly was utilized as the Ntype photothermal layer, and the PEDOT:PSS/PET film was utilized as the P-type thermal-expansion layer. Based on the thermoelectric and electronegative properties of the MCHF composite film, we propose two strategies to combine the light-driven actuation mechanism with the photo-thermoelectric effect (PTE) and triboelectric effect to endow the light-driven actuator perception capabilities. Based on the PTE effect, the MCHF-based bilayer film can be directly utilized as a PTE generator (Seebeck coefficient of 23.3 mu V K- 1) to simultaneously achieve lightdriven actuation and self-powered relative-temperature perception. When utilized as a triboelectric electrode (maximum output voltage of 144.7 V), the MCHF layer can trigger the triboelectric effect with the actuation force of the light-driven actuator, thus realizing self-powered material perception. Finally, we demonstrated an intelligent gripper capable of synergizing light-driven actuation and self-powered multi-modal perception by compactly integrating these two strategies, which can recognize susceptible signals accurately (accuracy of 98 %) with the assistance of a neural network. This work is promising to facilitate the intelligent interaction of Ti3C2Tx MXene-based soft robots with variable environments.