amino-substituted cobalt(iii)corrole: bifunctional electrocatalyst for oxygen … · 2019-06-21 ·...
TRANSCRIPT
S1
Amino-substituted Cobalt(III)Corrole: Bifunctional
Electrocatalyst for Oxygen and Hydrogen Evolution Reactions Amit Kumar, Sujesh S, Prachi Varshney, Amit Paul and Jeyaraman Sankar*
Department of Chemistry, Indian Institute of Science Education and Research Bhopal,
Bhopal Bypass Road, Bhopal, M.P–462066 (India)
Table of Contents:
1. Electrocatalytic calculations S2
2. Figures S3-S13
2.1. Fig. S1 ESI-HRMS of 5-(4-nitrophenyl)dipyrromethane [M + H]+ S3
2.2. Fig. S2 1H NMR spectrum of 5-(4-nitrophenyl)dipyrromethane S3
2.3. Fig. S3 ESI-HRMS of H3BNPC [M + H]+ S4
2.4. Fig. S4 1H and 19F NMR spectra of H3BNPC S5
2.5. Fig. S5 ESI-HRMS of H3BAPC [M + H]+ S6
2.6. Fig. S6 ESI-HRMS of Co(BAPC)Py2 [M – 2Py]+ S7
2.7. Fig. S7 1H and 19F NMR spectra of H3BAPC S8
2.8. Fig. S8 1H and 19F NMR spectra of Co(BAPC)Py2 S9
2.9 Fig. S9 UV-vis spectra of H3BAPC and Co(BAPC)Py2 in acetonitrile S10
2.10. Fig. S10 CV of Co(BAPC)Py2 in positive potential window with varying concentration
of catalyst and fixed amount of water S11
2.11. Fig. S11 CV of Co(BAPC)Py2 in negative potential window with varying concentration
of catalyst and fixed amount of TFA S12
2.12. Fig. S12 Chronoamperogram for Co(BAPC)Py2 catalyst for OER S13
3. References S14
Electronic Supplementary Material (ESI) for Dalton Transactions.This journal is © The Royal Society of Chemistry 2019
S2
1. Electrocatalytic calculations:
The electrochemical potential was converted relative to the normal hydrogen electrode (NHE;
all potentials reported in this work are referenced to the NHE) following a literature
protocol.S1 Current and peak potentials for the catalytic waves were compared without
addition of H2O or TFA (ip) and with addition of H2O or TFA (icat). Current ratios, icat/ip, were
plotted vs [H2O]1/2 and [TFA]1/2 to determine first order rate constants (k) using the of eq. 1
for OER and eq. 2 for HER.
𝑖𝑖𝑐𝑐𝑐𝑐𝑐𝑐𝑖𝑖𝑝𝑝
= (𝑅𝑅𝑅𝑅)1/2
0.446(𝑛𝑛𝑛𝑛𝑛𝑛)1/2 𝑘𝑘𝑐𝑐𝑐𝑐𝑐𝑐1/2 = (𝑅𝑅𝑅𝑅)1/2
0.446(𝑛𝑛𝑛𝑛𝑛𝑛)1/2 𝑘𝑘1/2(𝐻𝐻2𝑂𝑂)1/2 (1)
𝑖𝑖𝑐𝑐𝑐𝑐𝑐𝑐𝑖𝑖𝑝𝑝
= (𝑅𝑅𝑅𝑅)1/2
0.446(𝑛𝑛𝑛𝑛𝑛𝑛)1/2 𝑘𝑘𝑐𝑐𝑐𝑐𝑐𝑐1/2 = (𝑅𝑅𝑅𝑅)1/2
0.446(𝑛𝑛𝑛𝑛𝑛𝑛)1/2 𝑘𝑘1/2(𝑇𝑇𝑇𝑇𝑇𝑇)1/2 (2)
Wherein, R, T, n, F, and ν are the universal gas constant, temperature, number of electrons
transferred, Faraday constant, and scan rate, respectively.
The chronoamperometry experiment has been performed in stirring electrolyte
solution (1.0 M KOH), in order to make the solution free from in-situ generated oxygen
bubbles. A potential of 0.95 V versus NHE has been chosen for the chronoamperometry
experiment. The turnover number (TON) and turnover frequency (TOF) have been estimated
by using the eq. 3 and 4, wherein charge was calculated by integrating chronoamperogram.
The number of electron transfer for water oxidation is 4 and F represents the Faraday’s
constant.
𝑇𝑇𝑂𝑂𝑇𝑇 = 𝐶𝐶ℎ𝑐𝑐𝑎𝑎𝑎𝑎𝑎𝑎 4×𝑛𝑛× 𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐 𝑐𝑐𝑐𝑐𝑛𝑛𝑐𝑐𝑎𝑎𝑛𝑛𝑐𝑐𝑎𝑎𝑐𝑐𝑐𝑐𝑖𝑖𝑐𝑐𝑛𝑛 𝑖𝑖𝑛𝑛 𝑚𝑚𝑐𝑐𝑐𝑐𝑎𝑎𝑐𝑐
(3)
𝑇𝑇𝑂𝑂𝑇𝑇 = 𝑅𝑅𝑇𝑇𝑇𝑇𝑐𝑐𝑖𝑖𝑚𝑚𝑎𝑎 𝑓𝑓𝑐𝑐𝑎𝑎 𝑎𝑎𝑐𝑐𝑎𝑎𝑐𝑐𝑐𝑐𝑎𝑎𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑖𝑖𝑐𝑐 (𝑐𝑐)
(4)
S3
2. Figures.
Fig. S1 ESI-HRMS of 5-(4-nitrophenyl)dipyrromethane [M + H]+.
Fig. S2 1H NMR spectrum of 5-(4-nitrophenyl)dipyrromethane.
S4
Fig. S3 ESI-HRMS of H3BNPC [M + H]+.
S5
Fig. S4 1H and 19F NMR spectra of H3BNPC.
NN NNHH
HHNNNNHH
NNOO22
FF
OO22NN
FFFF
FF FF
NN NNHH
HHNNNNHH
NNOO22
FF
OO22NN
FFFF
FF FF
S6
Fig. S5 ESI-HRMS of H3BAPC [M + H]+.
S7
Fig. S6 ESI-HRMS of Co(BAPC)Py2 [M - 2Py]+.
S8
Fig. S7 1H and 19F NMR spectra of H3BAPC.
NN HHNN
HHNNNNHH
NNHH22
FF
HH22NN
FF FF
FFFF
S9
Fig. S8 1H and 19F NMR spectra of Co(BAPC)Py2.
β protons a b + Py
c Py
a b
c
NN NN
NNNN
NNHH22
FF
HH22NN
FF FF
FFFF
CoCo PyPyPyPy
S10
Fig. S9 UV-Vis spectra of H3BAPC (CH2Cl2, c; 0.62 × 10-6 M) and Co(BAPC)Py2
(CH2Cl2/Pyridine; 99/01, c; 0.43 × 10-6 M).
S11
(a)
(b)
Fig. S10 (a) Cyclic voltammograms of Co(BAPC)Py2 in acetonitrile solutions with varying
concentration of Co(BAPC)Py2 (0.5 mM - 2.0 mM) with 3% of water and (b) corresponding
linear plot for icat vs [cat], using 0.1 M nBu4NPF6 as supporting electrolyte with scan rate (ν)
of 50 mV s-1.
S12
(a)
(b)
Fig. S11 (a) Cyclic voltammograms of Co(BAPC)Py2 in acetonitrile solutions with varying
concentration of Co(BAPC)Py2 (0.5 mM - 2.0 mM) and fixed amount of TFA (10 equiv.) and
(b) corresponding linear plot for icat vs [cat], using 0.1 M nBu4NPF6 as supporting electrolyte
with scan rate (ν) of 50 mV s-1.
S13
Fig. S12 Chronoamperogram showing the stability up to 8.3 h at a constant potential of 0.95
V (vs. NHE) in 1.0 M KOH during water oxidation for Co(BAPC)Py2 catalyst. The redline
shows chronoamperogram in presence of catalyst while the black line represents chronoamperogram
without catalyst.
3. References
S1. V. V. Pavlishchuk and A. W. Addison, Inorg. Chim. Acta, 2000, 298, 97.