Supporting Information (SI) for Magnetic Co@g-C 3 N 4 Core-Shells on rgo Sheets for Momentum Transfer with Catalytic Activity toward Continuous-Flow Hydrogen Generation Shasha Duan, Guosheng Han, Yongheng Su, Xiaoyu Zhang, Yanyan Liu, Xianli Wu *, and Baojun Li *,, College of Chemistry and Molecular Engineering, Zhengzhou University, 100 Science Road, Zhengzhou 450001, P R China Henan Center for Disease Control and Prevention, 105 Nongyenan Road, Zhengzhou 450016, P R China Department of Chemistry, Tsinghua University, 1 Tsinghua Park, Beijing 100084, P R China * Corresponding Author. E-mail: wuxianli@zzu.edu.cn (X.L. Wu) and lbjfcl@zzu.edu.cn (B.J. Li). S-1
Scheme S1. Illustration of formation processes of Co 3 O 4 @g-c 3 N 4 and Co 3 O 4 @rgo. Figure S1. The XRD patterns of CNG-I before calcinations and after TG test in air. Figure S2. The (a) N 2 -adsorption isotherm curves and (b) pore width distribution of CNG-I. The N 2 sorption isotherms were measured on NOVA 1000e surface area and poresize analyzer (Quantachrome Instrument, USA) at 77 K. From the adsorption branch of isotherm curves in the P/P 0 range between 0.05 and 0.35, the specific surface areas of the CNG-I are calculated by the multi-point Brunauer Emmett Teller (BET) method. S-2
The pore size distribution was evaluated by the Barrett-Joyner-Halenda (BJH) model. The total pore volume was determined from the amount adsorbed at the relative pressure of about 0.99. Figure S3. The TG-DSC curves of g-c 3 N 4, g-c 3 N 4 -rgo and CNG-I in air and Ar atmospheres. Figure S4. The (a) fine spectrum of C1s of CNG-I and (b) of frech and used CNG-I catalysts. Table S1. Element information of CNG-I from XPS spectrum. Elements C1s N1s O1s Co2p3 Na1s Cl2p Atom ratio (%) 69.52 5.36 19.13 3.94 1.76 0.29 Binding energy (ev) 284.67 288.96 398.65 529.88 531.42 780.28 1071.54 197.73 Weight ratio (%) 57.62 5.18 21.19 16.05 ~ ~ S-3
Figure S5. The catalytic performances of other composites in hydrogen generation at 303 K. Figure S6. The CNG-I attracted on magneton in batch reactor. S-4
Figure S7. The catalytic performances of CNG-I in hydrogen generation at 303 K. (a, b, d, e) under various stirring rates from 0.1 M of NaBH 4 and (c, f) from various concentration of NaBH 4 under stirring rate of 500 rpm. (a-c) Magneton- stirring mode, (d-f) self-stirring mode, and (g) the recycling performance of CNG-I in batch reactor. S-5
Table S2. The hydrogenation generation specific rates and activation energies with various catalysts from literatures. Catalyst Catalyst Weight (mg) Hydride Maximun H 2 generation specific rate (ml min 1 g 1 ) Activation Energy (kj mol 1 ) Reference Pt/C 100 NaBH 4 23,000 (298 K) S1 Pt/CoO 3.8 NaBH 4 350 (293 K) S2 Pt/LiCoO 2 20 NaBH 4 3680 (303 K) 70.4 S3 Co@Pt core shell 7 NH 3 BH 3 5869 (303 K) S4 Raney Co 500 NaBH 4 267.5 (293 K) 53.7 S5 Raney Ni 50 Co 50 500 NaBH 4 648.2 (293 K) 52.5 S5 Cu/Co 3 O 4 12 NH 3 BH 3 1411 (298 K) S6 Co P B 15 NaBH 4 2120 (298 K) 32 S7 Octahedral CoO 20 NaBH 4 8333 (303 K) S8 CoO 10 NaBH 4 6130 (303 K) 45.94 S9 CCS/Co 20 NaBH 4 10400 (293 K) 21.51 S10 Co/IR-120 200 NaBH 4 200 (298 K) 66.67 S11 Ni Fe B 200 NaBH 4 2910 (298 K) 57.0 S12 Co Mo B 10 NaBH 4 4200 (303 K) 43.7 S13 Co Ni P/Pd TiO 2 25 NaBH 4 460 (298 K) 57.0 S14 Co W P NaBH 4 5000 (303 K) 22.8 S15 Co-B 250 NaBH 4 44.1 S16 There is still a puzzle about the magnetic property of CNG-n catalysts and the external magnetic field. Many substrates and products possess diamagnetism. They will get very weak repulsion force because of their very low (10 5 ) negative magnetic susceptibility (χ). Some para magnetic molecules will receive very weak attractive force because of their very low (10 5 ) positive magnetic susceptibility. The super paramagnetic materials often (generally) possess very high (10 3 ) positive magnetic susceptibility. The external magnetic field will be enough to drive and fix the catalysts. Compared to the high magnetic susceptibility of catalysts, the magnetic susceptibility of substrates and products can be ignored. Namely, the external magnetic field and magnetism of catalysts are not enough to affect the catalysis process. Even though, in very strong external magnetic field, the catalytic activity of magnetic NPs can be influenced positively. S17 19 S-6
Figure S8. The XRD pattern of used CNG-I after the first hydrogen generation. Figure S9. The TEM images of used CNG-I after the first hydrogen generation. S-7
Figure S10. The TEM images of used CNG-II after the first hydrogen generation. Figure S11. The hydrogen generation with CNG-II. References S1. Bai, Y.; Wu, C.; Wu, F.; Yi, B. Carbon-supported Platinum Catalysts for On-site Hydrogen Generation from S-8
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