SUPPORTING INFORMATION
Fe3C nanorods encapsulated in N-doped carbon nanotubes as active electrocatalysts for hydrogen evolution reaction
Lulu Zhang,a Yongting Chen,b Pingping Zhao,bWei Luo b,*, Shengli Chenb, Minhua Shaoa,c,*
aDepartment of Chemical and Biomolecular Engineering, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong
b College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, Hubei,
430072, PR China
cEnergy Institute, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon,Hong Kong
*; . Tel: +852-34692269
Figure S1. TEM image(a) andN element mapping image(b) of Fe3C@NCNTcomposite showing Fe3C nanorods encapsulated in N-doped carbon nanotubes.
Element / Fe / O / N / C
Atomic (%) / 0.2 / 4.5 / 3.6 / 91.7
Figure S2.XPS spectrum and composition of Fe3C@NCNT composite.
Figure S3. XPS spectrumofC 1sof Fe3C@NCNTcomposite.
Figure S4. Cyclic voltammogram in an Ar-saturated 0.1 M HClO4 solution, scanning rate = 50 mV s-1. Catalyst loading = 0.765 mg cm-2, scan range is 0.05-1.0V.
Figure S5. Durability testing in an Ar-saturated 0.5 M H2SO4 solution by cycling the electrode between 0.1 and -0.2 V (a), and in an Ar-saturated 1 M KOH solution by cycling the electrode between 0.1 and -0.4 V (b). Catalysts loading = 0.765 mg cm-2.
Figure S6.The most stable H adsorption configuration on a theoretical model of Fe3C (a) and Fe3C@CNT (b) (Top: top view; Bottom: side view) used in DFT calculations.
Figure S7.HRTEM image of Fe3C@NCNT with the insert showing the carbon layers.
Figure S8.Comparison of polarization curves of Fe3C@NCNT and Fe-N-C in a 0.5 M H2SO4 solution. Catalysts loading = 0.225 mg cm-2
.
Figure S9.Polarization curves of Fe3C@NCNT in a 1.0 M KOH solutionbefore and after 1500 cycles in 0.5 M H2SO4. Catalysts loading = 0.765 mg cm-2.
Table S1.Comparisons of HER activities of non-precious metal based and metal free catalysts in acid media.
Materials / Structure / Activity(overpotential) / Loading
(mg cm-2) / Reference
Fe3C@NCNT / Nanotube / 154 mV at 10mA cm-2 / 0.765 / This work
Co-N-C / 235 mV at 10mA cm-2 / 0.765 / 1
MoS2/SWCNT / Nanosheet / ~220 mV at 10 mA cm-2 / 0.171 / 2
WS2@HNCNF / Nanotube / ~270 mV at 10 mA cm-2 / 0.285 / 3
Co-NCNT / Nanotube / 260 mV at 10 mA cm-2 / 0.28 / 4
Co0.6Mo1.4N2 / Nanoparticle / 200 mV at 10 mA cm-2 / 0.24 / 5
g-C3N4 / Nanoribbon / 207 mV at 10 mA cm-2 / 0.143 / 6
g-C3N4@S–Se-pGr / Nanosheet / 300 mV at 10 mA cm-2 / 0.283 / 7
Co-NG / Nanosheet / ~160 mV at 10 mA cm-2 / 0.285 / 8
FeCo@NC / Nanoparticle / 262 mV at 10 mA cm-2 / 0.285 / 9
MoS2/Mo2C-NCNT / Nanotube / ~200 mV at 2 mA cm-2 / ~2 / 10
References
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