Supporting Information High Salt Removal Capacity of Metal-Organic Gel Derived Porous Carbon for Capacitive Deionization Zhuo Wang, Tingting Yan, Guorong Chen, Liyi Shi and Dengsong Zhang* Research Center of Nano Science and Technology, Shanghai University, No. 99 Shangda Road, BaoShan District, Shanghai 200444, P. R. China *: Corresponding authors. E-mail: dszhang@shu.edu.cn. Total No. of Pages: 9 (Pages S1-S9). Total No. of Figures: 2 (Figures S1-S2). Total No. of Tables: 2 (Table S1-S2). References: 17 (Ref S1-S6). S-1
Experiment section Characterization The surface morphology and structure of the as-synthesized porous carbon were observed by TEM (JEOL, JEM-200CX), SEM (JEOL, JEM-700F), and HRTEM (JEOL, JEM-2010F). XRD patterns were collected by a Rigaku D/MAX-RB with Cu Kα radiation (40 kv, 20 ma). The Raman spectra were recorded on a spectrometer (JY H800UV). Nitrogen sorption isotherms were performed on an ASAP 2020 (Micromeritics) at 77 K. The Brunauer-Emmett-Teller (BET) and nonlocal density functional methods were utilized to calculate the specific surface areas and the pore size distributions. Electrochemical measurements Electrochemical tests were performed in a conventional three-electrode system, in which the as-synthesized PC working electrode, a piece of graphite counter electrode, and a saturated calomel reference electrode were used. The working electrode was prepared by mixing the active material (80%), acetylene black (10%), and polytetrafluoroethylene (10%). The mixture was coated onto the surface of graphite paper, followed by drying in a conventional oven at 110 o C overnight. Cyclic voltammetry (CV) and electrochemical impedance spectroscope (EIS) were carried out using a CHI 660D. Galvanostatic charge-discharge was conducted on an automatic LAND battery test instrument. All measurements were conducted in a 0.5 M aqueous NaCl solution. The specific capacitance (C, in F g -1 ) was calculated based on the formula: C = ( IdV)/ 2 νδvm where I (A) and ν (V s -1 ) are the response current density and scan rate, respectively, dv (V) is the scan potential window, and m (g) is the mass of active electrode material. S-2
Figure S1. SEM images of PC600 (a), PC800 (b), and PC1000 (c). S-3
Table S1. Comparison of the specific capacitance of carbon materials reported in the literature. Electrode material solution C (F g -1 ) Ref. 3D hierarchically porous graphene 0.5 M NaCl 151.7 (1 mv s -1 ) S1 Graphene/carbon nanotube composites 0.5 M NaCl 175 (1 mv s -1 ) S2 Graphene 0.5 M NaCl 106 (1 mv s -1 ) S2 sponge-templated graphene 0.5 M NaCl 57 (10 mv s -1 ) S3 3D graphene-based hierarchically porous carbon 1 M NaCl 80.34 (10 mv s -1 ) S4 carbon nanotube/porous carbon polyhedra hybrid 1 M NaCl 104.2 (5 mv s -1 ) S5 carbon nanotube 1 M NaCl 37.7 (5 mv s -1 ) S5 PC800 0.5 M NaCl 213.1 (1 mv s -1 ) This work PC800 0.5 M NaCl 95.3 (5 mv s -1 ) This work PC800 0.5 M NaCl 64.2 (10 mv s -1 ) This work S-4
Table S2. Comparison of the salt removal capacity of various carbon materials from the literature. Applied Initial NaCl Salt adsorption Electrode material voltage concentration capacity Ref. (V) (mg/l) (mg/g) Carbon nanotubes 1.2 500 2.80 S6 Graphene nanosheets 2.0 250 8.60 S7 Graphene aerogel 1.2 500 9.90 S8 Nitrogen-doped graphene 1.8 100 4.81 S9 Mesoporous graphene 1.6 500 15.21 S10 Purified graphene 1.5 100 1.27 S11 3D-macroporous graphene architecture 3D-macroporous graphene hierarchically porous carbon 1.6 50 3.90 S12 1.2 25 6.18 S4 3D-macroporous graphene 1.2 500 14.7 S1 Carbon spheres 1.2 500 5.81 S13 Carbon nanorods 1.2 500 15.12 S14 3D-Graphene Architecture with Nanopores 1.6 500 15 S15 3D graphene 1.4 500 13.72 S16 Porous Carbon Spheres 1.6 500 5.81 S17 PC800 1.2 500 21.52 This work PC800 1.4 500 25.16 This work PC800 1.4 300 22.11 This work PC800 1.4 100 18.62 This work S-5
Figure S2. Current transient of PC800 in different concentrations of NaCl solution at 1.4 V. S-6
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