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.