Supporting Information
Hierarchical (Ni,Co)Se
2/Carbon Hollow Rhombic Dodecahedra Derived from Metal-Organic Frameworks for Efficient Water-Splitting Electrocatalysis
Fangwang Ming†, Hanfeng Liang,*, ‡Huanhuan Shi†, Gui Mei†, XunXu†, Zhoucheng Wang*, †
†College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
‡Materials Science and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia
E-mail: [email protected] (Z. Wang); [email protected] (H. Liang)
Additional Figures and Data
Fig. S1. XRD patterns of ZIF-67, NiCo LDH, and CoCo LDH.
Fig. S2. Structural characterization of the precursors. (a-c) SEM and (d-f) TEM images of ZIF-67
Fig. S3. (a) XPS survey spectrum of the CoSe2/NC-SRD. High resolution XPS spectra of (b) N 1s, (c) Co 2p, and (d) Se 3d regions.
Fig. S4. (a) XPS survey spectrum of the (Ni,Co)Se2/C-HRD. High resolution XPS spectra of (b) Co 2p, (c) Ni 2p, and (d) Se 3d regions.
Fig. S5. (a) XPS survey spectrum of the CoSe2/C-HRD. High resolution XPS spectra of (b) Co 2p, and (c) Se 3d regions.
Fig. S6. EDX spectra of the three as-synthesized selenides.
(a) CoSe2/NC-SRD, (b) (Ni,Co)Se2/C-HRD and (c) CoSe2/C-HRD.
Fig. S7. IR-corrected polarization curves of (Ni,Co)Se2/C-HRD, CoSe2/C-HRD, NiCo LDH and CoCo LDH for HER in 1M KOH.
Fig. S8. Electrochemical cyclic voltammetry curves at different scan rates for (a) CoSe2/NC-SRD, (b) (Ni,Co)Se2/C-HRD, and (c) CoSe2/C-HRD.
Fig. S9. Long-term stability test of (Ni,Co)Se2/C-HRD catalyst at 20 mA cm-2 for 36 h.
Fig. S10. (a) Polarizationcurves for (Ni,Co)Se2/C-HRD before and after 2000 CV cycles;
(b) corresponding Tafel plots.
Fig. S11. (a) SEM and (b) HRTEM images of the post-HER (Ni,Co)Se2/C-HRD catalyst.
Fig. S12. IR-corrected polarization curves of (Ni,Co)Se2/C-HRD, CoSe2/C-HRD, NiCo LDH and CoCo LDH for OER in 1M KOH.
Fig. S13. Polarization curves for the (Ni,Co)Se2/C-HRD atdifferent scan rates.
Fig. S14. Electrochemical cyclic voltammetry curves at different scan rates for (a) CoSe2/NC-SRD, (b) (Ni,Co)Se2/C-HRD and (c) CoSe2/C-HRD.
Fig. S15. (a) SEM and (b) HRTEM images of the post-OER (Ni,Co)Se2/C-HRD catalyst.
Fig. S16. (a) XPS survey spectrum of the post-OER (Ni,Co)Se2/C-HRD catalyst.
High resolution XPS spectra of (b) Co 2p, (c) Ni 2p, and (d) Se 3d regions.
Fig. S17. XRD patterns of (Ni,Co)Se2/C-HRD samples obtained at different thermalselenization temperatures (350, 400, and 450 °C).
Fig. S19. IR-corrected polarization curves of (Ni,Co)Se2/C-HRD for (a) HER, (b) OER, (c) overall water-splitting, respectively; (d) Time-dependent current density curve for (Ni,Co)Se2/C-HRD
under a static potential of 1.66 V for 20 h. All experiments were carried out in 6 M KOH.
Table S1.Comparison of the electrocatalytic HER activity of our catalyst and various non-precious catalysts in 1 M KOH.
Catalyst J
(mA cm-2) η
(mV) Tafel slope
(mV dec-1) Reference
Co-Ni-Se/C/NF 10 90 81 J. Mater. Chem. A, 2016, 4, 15148
Ni-NPs@NC 20 77 68 ACS Appl. Mater. Interfaces 2016, 8, 35390
Co0.85Se@NC 10 230 125 J. Mater. Chem. A, 2017, 5, 7001
Ni-Fe-P@C 10 233 92.6 J. Mater. Chem. A, 2017, 5, 2496
Co-P 10 94 42 Angew. Chem., Int. Ed., 2015, 54, 6251
Ni5P4 film 10 150 53 Angew. Chem.,2015, 127, 12538
NiSe/NF 10 96 120 Angew. Chem., Int. Ed., 2015, 54, 9351
Co@Co3O4-NC 10 221 77.3 J. Mater. Chem. A, 2017, 5, 9533
a-CoSe/Ti 10 121 84 Chem. Commun.,2015, 51, 16683
NiFe-MOF
(0.1 M KOH) 10 134 / Nat.Commun.,2017,8, 15341
CoSe2/NC-SRD/NF (Ni,Co)Se2/C-HRD/NF
CoSe2/C-HRD/NF 10 189
87 157
115 65
110 This work
Note: NF = Ni foam; CC = carbon cloth; a= amorphous; NC= N doped carbon.
Table S2. Comparison of the electrocatalytic OER activity of our catalyst and various non-precious catalysts in 1 M KOH.
Catalyst J
(mA cm-2) η
(mV) Tafel slope
(mV dec-1) Reference
Co-Ni-Se/C/NF 30
50 275
300 63 J. Mater. Chem. A, 2016, 4, 15148
NiSe/NF 20 270 64 Angew. Chem., Int. Ed., 2015, 54, 9351
Co3S4@MoS2 10 330 59 Chem. Mater.,2017, 29, 5566
FeNi@N-CNT 10 300 47.7 ACS Appl. Mater. Interfaces 2016, 8, 35390
Co0.85Se@NC 10 320 75 J. Mater. Chem. A, 2017, 5, 7001
CoSe2-450 10 330 79 J. Mater. Chem. A,DOI: 10.1039/c7ta04662f
ZIF-Co0.85Se 10 360 62 ACS Appl. Mater. Interfaces, 2016, 8, 20534
Co3O4/rGO-400 10 340 66 Chem. Sci., 2016, 7, 1690
Ni3Se2/CF 50 340 80 Catal. Sci. Technol., 2015, 5, 4954
Co-doped NiSe2 100 320 94 Nanoscale, 2016, 8, 3911
NiFe-MOF
(0.1 M KOH) 10 240 34 Nat.Commun.,2017,8, 15341
Table S3. Comparison of electrocatalytic activity for overall water splitting of our catalyst and various non-precious catalysts in 1 M KOH.
Catalyst Cell voltage (V) at 10 mA cm-2 Reference
Co-Ni-Se/C/NF 1.6 J. Mater. Chem. A, 2016, 4, 15148
NiSe/NF 1.63 Angew. Chem., Int. Ed., 2015, 54, 9351
Co0.85Se@NC 1.76 J. Mater. Chem. A, 2017, 5, 7001
Co@Co3O4-NC 2.004 J. Mater. Chem. A, 2017, 5, 9533
VOOH 1.62 Angew. Chem. 2017, 129, 588
Ni3Se2/CF 1.65 Catal. Sci. Technol., 2015, 5, 4954
FeNi@N-
CNT//NiNPs@NC 1.60 ACS Appl. Mater. Interfaces,2016, 8, 35390 NiFe-MOF
(0.1 M KOH) 1.55 Nat.Commun.,2017,8, 15341 Ni-Fe-P@C 1.52 J. Mater. Chem. A, 2017, 5, 2496 CoSe2/NC-SRD
(Ni,Co)Se2/C-HRD CoSe2/C-HRD
1.68 1.58
1.63 This work
Note: NF = Ni foam; CF= Cu foam; NC= N doped carbon.
