Supporting Information for

Transcription

1 Supporting Information for Epidermis Microstructure Inspired Graphene Pressure Sensor with Random Distributed Spinosum for High Sensitivity and Large Linearity Yu Pang,#, Kunning Zhang,#, Zhen Yang, Song Jiang, Zhenyi Ju, Yuxing Li, Xuefeng Wang, Danyang Wang, Muqiang Jian, Yingying Zhang, Renrong Liang, * He Tian *, Yi Yang *, Tian-Ling Ren * Institute of Microelectronics, Tsinghua University, Beijing, , China Department of Chemistry and Center for Nano and Micro Mechanics (CNMM), Tsinghua University, Beijing , China

2 The PDF file includes: Figure S1. Optical micrographs of micro-patterned PDMS. Figure S2. Contact angles of micro-patterned PDMS before and after oxygen plasma treatment. Figure S3. Optical micrographs of GO/PDMS composites. Figure S4. Optical micrographs of rgo/pdms composites. Figure S5. 3D morphology of micro-patterned PDMS. Figure S6. SEM images of rgo/pdms samples. Figure S7. Cycle performance of relative resistance change at applied pressure of 12 kpa. Figure S8. The pressure distribution of simulation results for different geometries. Figure S9. Breath-ability of graphene pressure sensor attached on the volunteer s arm for two days. Scale bar is 1.5 cm. Figure S10. Durability test of the RDS graphene pressure sensor against steel rod. Scale bars is 1 cm. Figure S11. The RDS graphene pressure sensor for finger pulse monitoring. Figure S12. The detected signals of RDS graphene pressure sensor when loudspeaker spoke sensor. Figure S13. The application of RDS graphene pressure sensor for throat phonation. Figure S14. The RDS graphene pressure sensor for sentence recognition. Figure S15. The detected signals of RDS graphene pressure sensor for natural voice. Figure S16. The signals of hand and arm motion detection.

3 Figure S1. Optical micrographs of micro-patterned PDMS. Optical micrographs of the micro-patterned PDMS using different abrasive papers No. (A) 280, (B) 400, and (C) 600. Figure S2. Contact angles of micro-patterned PDMS before and after oxygen plasma treatment. Figure S3. Optical micrographs of GO/PDMS composites. The optical micrographs of the GO/PDMS using different abrasive papers No. (A) 280, (B) 400, and (C) 600.

4 Figure S4. Optical micrographs of rgo/pdms composites. The optical micrographs of the rgo/pdms using different abrasive papers No. (A) 280, (B) 400, and (C) 600, showing that large RDS density owns light color.

5 Figure S5. 3D morphology of micro-patterned PDMS. The 3D morphology of micro-patterned PDMS pressure sensor using abrasive paper No. (A) 150, (D) 280, and (G) 400; height profile corresponding to marked line on the diagonals using abrasive paper No. (B) 150, (E) 280, and (H) 400; probability distribution and cumulative distribution of the height for the spinosum structure using abrasive paper No. (C) 150, (F) 280, and (I) 400.

6 Figure S6. SEM images of rgo/pdms samples. The SEM images and high magnified SEM images of the rgo/pdms samples using abrasive paper No. (A-B) 150, (C-D) 280, and (E-F) 400. Figure S7. Cycle performance of relative resistance change at applied pressure of 12 kpa.

7 Figure S8. The pressure distribution of simulation results for different geometries. The pressure distribution of simulation results for different geometries of (A) pyramid, (B) hemisphere, (C) nanowire and (D) RDS microstructure at a high loading pressure of 15 kpa. Figure S9. Breath-ability of graphene pressure sensor attached on the volunteer s arm for two days. Scale bar is 1.5 cm. Figure S10. Durability test of the RDS graphene pressure sensor against steel rod. Scale bars is 1 cm.

8 Figure S11. The RDS graphene pressure sensor for finger pulse monitoring. The photographs of pressure sensor assembled on (A) finger tips, and the corresponding signals of the (B) finger pulse and the (C) details of one pulse for finger pulse clearly showing two characteristic peaks. Figure S12. The detected signals of RDS graphene pressure sensor when loudspeaker spoke sensor.

9 Figure S13. The application of RDS graphene pressure sensor for throat phonation. Photograph of pressure sensor attached on (A) human throat, and the corresponding signals when he phonated (B) graphene and (C) sensor. Figure S14. The RDS graphene pressure sensor for sentence recognition. (A) The detected repeatable signal and (B) one magnified typical signal of pressure sensor when the loudspeaker phonated the sentence graphene pressure sensor is used for electronic skin.

10 Figure S15. The detected signals of RDS graphene pressure sensor for natural voice. The detected signals of pressure sensor corresponding to sound of (A) bird chirp, (B) deer bleat, (C) temple bell and (D) ceramic peening. Figure S16. The signals of hand and arm motion detection. (A) The photography of pressure sensor attached on palm and (B) detected signal for human push-up; (C) The photography of pressure sensor attached on brachioradialis and (D) detected signal for arm bending.

11 Table S1. The comparison of sensitivities and linearity range for previous reported pressure sensors. Microstructure surface Sensitivity (kpa -1 ) a) Linearity limitation (kpa) Working principle Ref. Pyramid piezoresistive (39) Pyramid capacitance (36) Pyramid capacitance (34) Pyramid capacitance (38) Pyramid piezoelectric (35) Hemisphere piezoresistive (44) Dome piezoresistive (45) Cylinder piezoresistive (22) Pyramid & Cylinder capacitance (37) Nanowire piezoresistive (21) Nanowire capacitance (43) Nanowire piezoresistive (41) Pillar piezoresistive (23) Pillar & nanowire piezoresistive (40) Prism piezoresistive (47) Wave capacitance (42) RDS piezoresistive this work a) Note that all the sensitivities have defined as an absolute value.