Supporting Information

Transcription

1 Supporting Information A Robust Versatile Hybrid Electrocatalyst for the Oxygen Reduction Reaction Kun Wang, Yi Wang*, Yexiang Tong, Zhangweihao Pan, Shuqin Song* a The Key Lab of Low- Chemistry & Energy Conservation of Guangdong Province, School of Materials Science and Engineering, Sun Yat-sen University, Guangzhou , China. b School of Chemical Engineering and Technology, Sun Yat-sen University, Zhuhai , China. c School of Chemistry, Sun Yat-sen University, Guangzhou , China *Shuqin Song: stsssq@mail.sysu.edu.cn; *Yi Wang: wangyi76@mail.sysu.edu.cn. S-1

2 X 1.4 WC-FeWO X 4 WC/OMC C WC FeWO 2θ (degree) 4 Figure S1 XRD patterns of WC/OMC and WC-FeWO Figure S2 Small-angle XRD patterns of WC/OMC and WC-FeWO S-2

3 Figure S3 N 2 adsorption-desorption isotherms of WC/OMC and WC-FeWO Figure S4 The high-resolution C1s XPS spectra of the WC-FeWO S-3

4 Figure S5 The high-resolution W4f XPS spectra of the WC/OMC. Figure S6 Raman spectra of the FeN-C, WC/OMC and WC-FeWO respectively and their corresponding intensity ratio of G-band to D-band (I G :I D ). S-4

5 Figure S7 Cyclic voltammograms of FeN-C (a) and WC/OMC (b) for the ORR in N 2 - or O 2 - saturated 0.5 mol/l H 2 SO 4 solutions at a scan rate of 20 mv/s. S-5

6 Figure S8 RDE voltammograms for the WC-FeWO hybrid at various rotation speeds (scan rate: 20 mv/s) (a) and the K-L plots at different potentials (b) in an O 2 -saturated 0.5 mol/l H 2 SO 4 solution. S-6

7 Figure S9 Cyclic voltammograms for the WC-FeWO hybrid (a) and the commercial Pt/C (b) in O 2 -saturated 0.5 mol/l H 2 SO 4 solutions with or without 0.5 mol/l methanol at a scan rate of 20 mv/s. S-7

8 Figure S10 Cyclic voltammograms of FeN-C (a) and WC/OMC (b) for ORR in N 2 - or O 2 - saturated 0.1 mol/l KOH solution at a scan rate of 20 mv/s. S-8

9 Figure S11 Cyclic voltammograms (scan rate: 20 mv/s) for the WC-FeWO (a) and the commercial Pt/C (b) in O 2 -saturated 0.1 mol/l KOH solution with or without 0.5 mol/l methanol. S-9

10 Table S1. Summary of reported ORR performance of non-noble-metal doped catalysts. All catalysts were tested in acidic media. Catalyst Catalyst loading (µg/cm 2 ) Half-wave potential (V vs. RHE) Limiting current density (ma/cm 2 ) Scanning rate/rotation rate (mv/s)/(rpm) References PANI-Fe-C ~3.8 10/900 Science, 2011, 332, 443 PANI-Co-C ~3.5 10/900 Science, 2011, 332, 443 Nitrogen-doped hierarchically porous N-doped mesoporous graphene ~4.5 10/1600 Nat. Commun., 2014, 5, ~5.0 10/1600 Angew. Chem. Int. Ed., 2014, 53, 1570 N-doped spheres ~6.4 10/1600 Adv. Mater., 2013, 25, 998 N-doped nanoporous 3D N and P co-doped mesoporous nano foams Iron carbide nanoparticles encapsulated in mesoporous Fe-N-Doped nanofibers ~3.4 20/1600 Energy Environ. Sci., 2014, 7, ~5.5 5/1600 Nat. nanotechnol., 2015, 48, ~5.0 10/1600 Angew. Chem. Int. Ed., 2015, 54, 1 WC-FeWO 4@FeN-OMC a) ~4.3 20/1600 this work Pt/C (20 wt. %) 30 µg Pt/cm a) ~4.6 20/1600 this work a) Conversions of reference electrodes into RHE scale were based on the calibration measurement results: E (RHE) =E (SCE) V S-10

11 Table S2. Summary of reported ORR performance of non-noble-metal doped catalysts. All catalysts were tested in 0.1 M KOH/NaOH. Catalyst Catalyst loading (µg/cm) Half-wave potential (V vs. RHE) Limiting current density (ma/cm 2 ) Scanning rate/rotation rate (mv/s)/(rpm) References Nitrogen doped tube/nanoparticle composite ~ mv potential step and 25 s potential hold time at very step/900 Nat. Commun., 2013, 4, 1922 Co 3O 4 nanocrystals on N- doped graphene Nitrogen-doped hierarchically porous Mesoporous ironnitrogen-doped N-doped mesoprous Iron nanoparticles encapsulation with nitrogen-doped nanoshell N-doped nanoporous Porous doped nanofibers Co@Co 3O 4@C core@bishell nanoparticles into porous Bamboo-like nanotube/fe 3C nanoparticle 3D N and P co-doped mesoporous nano foams Iron carbide nanoparticles encapsulated in mesoporous Fe-N-Doped nanofibers ~5.0 5/1600 Nat. Mater., 2011, 10, ~5.8 10/1600 Nat. Commun., 2014, 5, ~5.5 10/1600 Angew. Chem. Int. Ed., 2015, 54, ~6.3 10/1600 J. Am. Chem. Soc., 2010, 133, ~6.1 10/1600 Nano Energy, 2015, 13, ~4.8 20/1600 Energy Environ. Sci., 2014, 7, ~5.6 10/1600 J. Am. Chem. Soc., 2014, 136, ~4.6 10/1600 Energy Environ. Sci., 2015, 8, ~5.8 5/1600 J. Am. Chem. Soc., 2015, 137, ~4.5 5/1600 Nat. Nanotechnol., 2015, 48, ~5.5 10/1600 Angew. Chem. Int. Ed., 2015, 54, 1 WC-FeWO 4@FeN-OMC a) ~6.4 20/1600 this work Pt/C (20 wt. %) 30 ug Pt/cm a) ~5.5 20/1600 this work a) Conversions of reference electrodes into RHE scale were based on the calibration measurement results: E (RHE) =E (Hg/HgO) V *pH S-11