Supporting Information

Transcription

1 Copyright WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim, Germany, Supporting Information for Small., DOI: /smll Transparent Conducting Films of Hierarchically Nanostructured Polyaniline Networks on Flexible Substrates for High-Performance Gas Sensors Shouli Bai, Chaozheng Sun, Pengbo Wan,* Cheng Wang, Ruixian Luo, Yaping Li, Junfeng Liu, and Xiaoming Sun*

2 Supporting Information Transparent Conducting Film of Hierarchically Nanostructured Polyaniline Networks on Flexible Substrate for High-Performance Gas Sensor Shouli Bai, Chaozheng Sun, Pengbo Wan,* Cheng Wang, Ruixian Luo, Yaping Li, Junfeng Liu, and Xiaoming Sun* State Key Laboratory of Chemical Resource Engineering, College of Science, P.O. Box 98, Beijing University of Chemical Technology, Beijing , P. R. China Figure S1. Meyer-rod coating of Ag NWs on PET. a) Meyer-rod coating setup for Ag NW coating on flexible PET substrate. b) Finished Ag NW film coating on PET substrate. The sheet resistance is ~ 46Ω/. The Ag NW TCF completing an electrical circuit with a battery pack and a LED before c) and after d) bending. 1

3 Figure S2. SEM image of Ag NW networks on PET. Figure S3. SEM images of different particle-like PANI structures by dipping PET in aniline polymerizing solution with dipping time of a) 5 min, b) 10 min, c) 20 min and d) 30 min, respectively. 2

4 Figure S4. a) Transmittance spectra of the various particle-like PANI with immersion time of 5 min, 10 min, 20 min and 30 min on PET substrates, respectively. The optical transmittance of the corresponding film altered from 85% at 550 nm, to 95%, 84%, 78% and 80% for 5 min, 10 min, 20 min, and 30 min polymerization, respectively. b) Photographs of transparent particle-like PANI films on PET substrates with the immersion time of 5 min, 10 min, 20 min and 30 min from left to right. The words BUCT are placed behind the films. The conductivity of the film varied from non-conducting states for PET substrate, 5 min and 10 min polymerization, to conducting states for 20 min (sheet resistance at 46 kω/ ) and 30 min (sheet resistance at 7.5 kω/ ) polymerization. 3

5 Figure S5. a) FTIR spectra of the hierarchically nanostructured PANI (red line) and the particle-like PANI (black line) at the immersion time of 20 min. b) The integrated benzenoid rings peak intensity (I 1 ) and quinoid rings peak (I 2 ) intensity of particle-like pure PANI and the hierarchically nanostructured PANI. And the realted ratio I 1 /I 2 for particle-like pure PANI and the hierarchically nanostructured PANI. Figure S6. UV-vis spectra of Ag NWs (black line), the hierarchically nanostructured PANI (blue line), and the particle-like PANI (red line). 4

6 Figure S7. a) XRD patterns of different functional films: 1) PET substrate; 2) Ag NW TCF on PET; 3) the particle-like PANI on PET with the immersion time of 20 min; 4) the hierarchically nanostructured PANI networks with AgCl on PET with the immersion time of 20 min. b) XRD patterns of different PANI powders collected from the precipitates in the reaction solutions for obtaining 5) pure PANI powder with reaction time of 20 min and 6) PANI powder containing AgCl with reaction time of 20 min. The characteristic peaks appear at 9.16, 15.78, and from XRD patterns of different PANI powders collected from the precipitates in the related reaction solutions (Figure S6b), which are attributed to crystallized PANI. Especially, the strongest peak at ~25 could be assigned to the face to face interchain stacking distance between phenyl rings. The remaining diffraction peaks in Figure S6b for the hierarchically nanostructured PANI were consistent with diffraction data of AgCl, indicating the transformation of silver to silver chloride in the synthesis of hierarchically nanostructured PANI. 5

7 Figure S8. XPS spectra of a) hierarchically nanostructured PANI (20min sample), b) the XPS peaks of Ag 3d 5/2 ( ev) and Ag 3d 3/2 ( ev) indicating the formation of Ag + in the hierarchically nanostructured PANI, c) the C 1s peak ( ev) and d) N 1s peak ( ev) from C and N elements of PANI. Figure S9. a) The sensitivity of the hierarchically nanostructured PANI-containing transparent film increaseed gradually with the increase of the concentration of NH 3, showing a linear relationship. b) The gas sensing property of the hierarchically nanostructured PANIcontaining transparent film and the particle-like PANI with both the polymerization time at 30 min, upon exposure to different concentrations of NH 3 from 5 to 100 ppm at room temperature. 6

8 Figure S10. TEM image of the hierarchically nanostructured polyaniline, demonstrating a core-shell structure with AgCl scattering inside. Figure S11. The selectivity of the sensor (20 min sample) to alkylamines. 7