Supporting Information. Fully-printed Ultra-flexible Supercapacitor Supported by a Single-textile Substrate

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1 Supporting Information Fully-printed Ultra-flexible Supercapacitor Supported by a Single-textile Substrate Huihui Zhang a,b, Yan Qiao a,b and Zhisong Lu a,b* a Chongqing Key Laboratory for Advanced Materials & Technologies of Clean Energies, Southwest University, 1 Tiansheng Road, Chongqing , P. R. China b Institute for Clean Energy & Advanced Materials, Faculty of Materials and Energy, Southwest University, 1 Tiansheng Road, Chongqing , P. R. China. *: Authors to whom correspondence should be addressed. Tel.: ; Fax: zslu@swu.edu.cn. S-1

2 Synthesis of active materials A. flavus GZ-6 was kindly provided by Institute of Agro-Products Processing Science and Technology, Chinese Academy of Agricultural Sciences, P. R. China. Potato dextrose agar (PDA) was purchased from Hope Bio-Technology (Qingdao, China). Conidium was collected and dried at room temperature, followed by a calcination at 900 ºC for 2 h under argon atmosphere to obtain conidium-derived carbon with a hollow spherical structure 1. The carbon spheres (30 mg) were dispersed in 50 ml water under ultra-sonic irradiation at room temperature for 10 min. Then, 50 mg KMnO 4 was slowly added into the solution, stirring for 2 h at 70 ºC to produce the MnO 2 nanosheets-decorated conidia carbon (MnO The final products were collected by filtration, washing several times with water and absolute ethanol in sequence 2. Calculation of area capacitance, energy and power density. Area capacitance (C area ) values were calculated from CV data and galvanostatic charge/discharge curves according to: Carea= (1) = (2) where, A is the area of active material on electrodes (cm 2 ), is the scan rate(mv s -1 ), V is the potential window of the CV, is the voltammetric current (A), t is the discharging time(s). The areal energy density and power density were obtained by Earea= (3) Parea= (4) S-2

3 Figure S1. Morphologies and XRD patterns of the MnO (A) SEM images of MnO (B) SEM images of MnO with higher magnification. (C) XRD patterns of CC and MnO Morphologies of the composite were investigated using FESEM. As shown in Figure. S1A, microspheres with a lot of wrinkles appear on the surface. The average diameter of the conidium-derived carbon is 1.5 µm. Figure.S1B shows that a uniform and dense layer of well-aligned MnO 2 nanosheets cover on the surface of hollow carbon spherical skeleton. XRD was carried out to further verify the growth of MnO 2 on the carbon microspheres. The XRD pattern of conidium-derived carbon exhibits two strong broad diffraction peak at about 2θ= 23 and 44, respectively, which can be ascribed to the graphitic carbon structure (Fig. S1C). The MnO 2 -modified carbon spheres have four characteristic peaks at 12.5, 25.2, 37.3 and 65.6, which correspond to the (001), (002), (-111) and (020) planes of δ-mno 2 (JCPDS ), respectively. S-3

4 Figure S2. CV curves of the silk fabric-supported supercapacitors with (red) or without (black) the active materials at a scan rate of 50 mv/s. Figure S3. CV curves of an as-prepared two textile-based supercapacitor rolled on pens with different diameters. S-4

5 Figure S4. SEM images of supercapacitor device at different number of bending (A and B) and twisting (D and E), Test picture of supercapacitor device at bending (C) and twisting (F). Figure S5. Ragone plot of the silk fabric-supported supercapacitor Ragone plot was shown in Fig. S5 to relate energy density (E) to power densities (P). All data in the Ragone plot were derived from the GCD curves. The maximum energy S-5

6 density of the wearable supercapacitor is 2.31 µwh cm -2 at the power density of mw cm -2. References 1. Liu, S.; Mao, C.; Wang, L.; Jia, M.; Sun, Q.; Liu, Y.; Xu, M.; Lu, Z. Bio-inspired Synthesis of Carbon Hollow Microspheres From Aspergillus Flavus Conidia for Lithium-ion Batteries. RSC Adv. 2015, 5 (73), Lei, Z.; Zhang, J.; Zhao, X. Ultrathin MnO 2 Nanofibers Grown on Graphitic Carbon Spheres as High-performance Asymmetric Supercapacitor Electrodes. J. Mater. Chem. 2012, 22 (1), S-6