a Supporting information Core-Shell Nanocomposites Based on Gold Nanoparticle@Zinc-Iron- Embedded Porous Carbons Derived from Metal Organic Frameworks as Efficient Dual Catalysts for Oxygen Reduction and Hydrogen Evolution Reactions Jia Lu a, Weijia Zhou a *, Likai Wang a, Jin Jia a, Yunting Ke a, Linjing Yang a, Kai Zhou a, Xiaojun Liu a, Zhenghua Tang a, Ligui Li a, Shaowei Chen a,b * New Energy Research Institute, School of Environment and Energy, South China University of Technology, Guangzhou Higher Education Mega Center, Guangzhou, Guangdong 510006, China b Department of Chemistry and Biochemistry, University of California, 1156 High Street, Santa Cruz, California 95064, United States * Emails: eszhouwj@scut.edu.cn (W. J. Z.); shaowei@ucsc.edu (S. W. C.) Table S1. Elemental compositions of Au@Zn-Fe-C hybrids prepared at different Au/Fe molar ratios Au/Fe molar ratio C (at.%) Au (at.%) Fe (at.%) Zn (at.%) 1:2 78.3 4.7 9.7 7.3 1:1 82.3 3.2 5.9 8.6 2:1 83.5 2.2 3.7 10.6 Table S2. Comparison of the ORR catalytic performance of Au@Zn-Fe-C with other catalysts derived from MOFs (at the electrode rotation rate of 1600 rpm) Catalysts Onset potential Current density at +0.4 V (ma n Electrolyte Ref. (V vs. RHE) cm -2 ) Au@Zn-Fe-C +0.94 2.63 3.26-3.82 0.1 M KOH this work N,S-porous carbon +0.96 2.5-2.7 3.4-3.8 0.1 M KOH 1 N-graphene/Co-embedded porous carbon +0.97 7.53 3.90-3.94 0.1 M KOH 2 N-doped porous carbon +0.87 3.6-3.8 3.68-3.8 0.1 M KOH 3 N-doped porous carbon nanopolyhrdra +0.95 4.2-4.4 3.8-3.9 0.1 M KOH 4 N-doped carbon nanotubes +0.95 5.6-5.8 3.78-3.86 0.1 M KOH 5 N-decorated nanoporous carbon +0.83 3.5-3.6 3.3 0.1 M KOH 6 SI-1
Table S3. Comparison of the HER activity of Au@Zn-Fe-C in 0.5 M H 2 SO 4 with results of relevant HER catalysts reported in recent literature Catalysts Onset E @ j = 10 Tafel slope potential ma cm -2 (mv dec -1 ) (V vs. RHE) (V vs. RHE) Ref. Au@Zn-Fe-C 0.08 130 0.123 this work MOFs-derived MoC X octahedrons 0.025 53 0.142 7 N-graphene/Co-embedded porous carbon derived from MOFs 0.058 126 0.229 2 GO/Cu-MOF 0.087 84 8 Co embedded N-rich CNTs 0.05 69 0.26 9 FeCo@NCNTs 0.07 74 0.275 10 Single-shell carbon encapsulated Fe nanoparticles 0 40 0.077 11 N-doped hexagonal carbon 0.065 56.7 0.18 12 N,S-graphene 0.13 80.5 0.28 13 N,P-graphene 91 0.42 14 MoS 2 /RGO 0.1 41 15 SI-2
Figure S1. TGA curves of (a) Zn-Fe-MOF and (b) Au@Zn-Fe-MOF. Figure S2. (a) SEM image and (b) XRD patterns of Zn-Fe-MOF. Zn-Fe-MOF possessed a regular octahedral morphology, with an average length of ca. 200 nm, and the XRD patterns of Zn-Fe-MOF were consistent with the results of Wang et al. 16 Figure S3. Particle size distributions of (a) Au nanoparticle cores and (b) Au@Zn-Fe-C core-shell hybrids. Data were obtained from TEM measurements as shown in Figure 2. Figure S4. (a) Nitrogen adsorption/desorption isotherms and (b) pore size distributions of Zn-Fe-C and Au@Zn-Fe-C. The corresponding BET values are 19.4 and 8.7 m 2 /g, respectively. SI-3
Figure S5. a) RRDE voltammograms of Zn-Fe-MOF pyrolyzed at different temperatures at a rotation rate of 1600 rpm in an O 2 -saturated 0.1 M KOH solution at 10 mv s 1. (b) Polarization curves of Zn- Fe-MOF pyrolyzed at different temperature at 5 mv s 1 in a 0.5 M H 2 SO 4 solution (ir-corrected). Figure S6. (a) RRDE voltammograms of Au@Zn-Fe-C and 20 wt% Pt/C at a rotation rate of 1600 rpm in O 2 -saturated 0.1 M KOH solution at 10 mv s 1. (b) Corresponding number of electron transfer (n). Figure S7. Cyclic voltammograms of (a) Zn-Fe-C and (b) Au@Zn-Fe-C in N 2 and O 2 -saturated 0.1 M KOH at 50 mv s 1. It can be seen that the reduction peak of Au@Zn-Fe-C (+0.67 V vs. RHE) was more positive that that of Zn-Fe-C (+0.55 V vs. RHE), suggesting a higher ORR activity. Figure S8. TEM images of Au nanoparticles. SI-4
Figure S9. (a) RDE voltammograms of Zn-C, Au@Zn-C, Au@Zn-Fe-C at a rotation rate of 1600 rpm in an O 2 -saturated 0.1 M KOH solution at 10 mv s 1. (b) Polarization curves of Zn-C, Au@ Zn-C, and Au@Zn-Fe-C at 5 mv s 1 in a 0.5 M H 2 SO 4 solution (ir-corrected). Figure S10. (a) RRDE voltammograms of Au@Zn-Fe-C with different Au/Fe ratios at a rotation rate of 1600 rpm in O 2 -saturated 0.1 M KOH solution at 10 mv s -1. (b) Corresponding number of electron transfer (n). Figure S11. Time dependence of the HER current density of Au@Zn-Fe-C loaded on glass carbon electrode at 0.15 V vs. RHE (ir-uncorrected). Inset is the photo image of H 2 bubbles formed on the electrode surface. Figure S12. (a) RRDE voltammograms of Au/Zn-Fe-C and Au@Zn-Fe-C at a rotation rate of 1600 rpm in an O 2 -saturated 0.1 M KOH solution at 10 mv s 1. (b) Polarization curves of Au/Zn-Fe-C and Au@Zn-Fe-C at 5 mv s 1 in a 0.5 M H 2 SO 4 solution (ir-corrected) SI-5
Figure S13. (a) RRDE voltammograms of pure Pt nanoparticles and Pt@Zn-Fe-C at a rotation rate of 1600 rpm in an O 2 -saturated 0.1 M KOH solution at 10 mv s 1. (b) Polarization curves of pure Pt nanoparticles and Pt@Zn-Fe-C at 5 mv s 1 in a 0.5 M H 2 SO 4 solution. References 1. Li, J.; Chen, Y.; Tang, Y.; Li, S.; Dong, H.; Li, K.; Han, M.; Lan, Y.-Q.; Bao, J.; Dai, Z., J. Mater. Chem. A 2014, 2, 6316-6319. 2. Hou, Y.; Wen, Z.; Cui, S.; Ci, S.; Mao, S.; Chen, J., Adv. Funct. Mater. 2015, 25, 872-882. 3. Zhang, P.; Sun, F.; Xiang, Z.; Shen, Z.; Yun, J.; Cao, D., Energy Environ. Sci. 2014, 7, 442-450. 4. Zhang, L.; Su, Z.; Jiang, F.; Yang, L.; Qian, J.; Zhou, Y.; Li, W.; Hong, M., Nanoscale 2014, 6, 6590-6602. 5. Su, P.; Xiao, H.; Zhao, J.; Yao, Y.; Shao, Z.; Li, C.; Yang, Q., Chem. Sci. 2013, 4, 2941-2946. 6. Aijaz, A.; Fujiwara, N.; Xu, Q., J. Am. Chem. Soc. 2014, 136, 6790-6793. 7. Wu, H. B.; Xia, B. Y.; Yu, L.; Yu, X.-Y.; Lou, X. W., Nat. Commun. 2015, 6, 6512-1. 8. Jahan, M.; Liu, Z.; Loh, K. P., Adv. Funct. Mater. 2013, 23, 5363-5372. 9. Zou, X.; Huang, X.; Goswami, A.; Silva, R.; Sathe, B. R.; Mikmeková, E.; Asefa, T., Angew. Chem. 2014, 126, 4461-4465. 10. Deng, J.; Ren, P.; Deng, D.; Yu, L.; Yang, F.; Bao, X., Energy Environ. Sci. 2014, 7, 1919-1923. 11. Tavakkoli, M.; Kallio, T.; Reynaud, O.; Nasibulin, A. G.; Johans, C.; Sainio, J.; Jiang, H.; Kauppinen, E. I.; Laasonen, K., Angew. Chem. 2015, 127, 4618-4621. 12. Liu, Y.; Yu, H.; Quan, X.; Chen, S.; Zhao, H.; Zhang, Y., Sci. Rep. 2014, 4, 6843-1. 13. Ito, Y.; Cong, W.; Fujita, T.; Tang, Z.; Chen, M., Angew. Chem. Int. Ed. 2015, 54, 2131-2136. 14. Zheng, Y.; Jiao, Y.; Li, L. H.; Xing, T.; Chen, Y.; Jaroniec, M.; Qiao, S. Z., ACS Nano 2014, 8, 5290-5296. 15. Li, Y.; Wang, H.; Xie, L.; Liang, Y.; Hong, G.; Dai, H., J. Am. Chem. Soc. 2011, 133, 7296-7299. 16. Zhang, Z. C.; Chen, Y. F.; Xu, X. B.; Zhang, J. C.; Xiang, G. L.; He, W.; Wang, X. Angew. Chem. Int. Ed. 2014, 53, 429-433. SI-6