fig2

Figure 2. Characterization and measurements of the sensor. (A) Photograph and SEM images of the MXene/dust-free paper-sensitive layer; (B) Elemental mapping of C, O, and Ti in the sensitive layer; (C) Photograph of the interdigital silver electrode layer and SEM image showing the cross-sectional view; (D) Photograph of the assembled paper-based sensor and SEM images showing the cross-sectional view; (E) Measurement of the resistance of the sensitive layer after 1,000 bending cycles; (F) Measurement of breathability between the paper-based sensor and other films; (G) Photographs showing the skin status after being covered by the paper-based sensor and PDMS film for 10 days; (H) Influence of temperature on the sensor. SEM: Scanning electronic microscopy; PDMS: poly(dimethylsiloxane).