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TRANSCRIPT
A comparative experimental and theoretical
investigation on energy storage performance of
CoSe2, NiSe2 and MnSe2 nanostructures
Mansi Pathak,1 Dipti Tamang,2 Manikandan Kandasamy,3 Bramhananda Chakraborty, 4,.* and
Chandra Sekhar Rout, 1*
1 Centre for Nano and Material Science, Jain global campus, Jakkasandra, Ramanagaram,
Banglore - 562112, India.
2School of Basic Sciences, Indian Institute of Technology, Bhubaneshwar, India
3 Nonlinear Optical Materials Laboratory, School of Physics, Bharathidasan University,
Tiruchirappalli-620024, Tamil Nadu, India.
4High Pressure and Synchrotron Radiation Physics Division, Bhabha Atomic Research Centre,
Mumbai- 400085, India.
Supporting information
Specific capacitance calculated using cyclic voltammetry,
1
Csp= areaunder the CV curve2 x scanrate x potential window xmass of electrode
Specific capacitance calculated using charge-discharge cycle,
Csp= current x dischargetimemass x potential window
Current/mass is given by current density i,e, A/g and discharge time/ potential window can be
obtained by the slope of the discharging curve from galvanostatic charge-discharge plot (∆t/∆V).
Energy density of symmetric cell is calculated using following formula,
Ed=12
Csp x( ΔV )2
Where, Csp is a specific capacitance calculated from GCD and ΔV is the potential window.
(Wh/kg)
Power density of symmetric cell is calculated by using following formula,
Pd=EdΔt
Where, Ed is the energy density and Δt is the discharging time. (W/kg)
2
Results and discussion:
Figure S1: (a-b) FESEM images of CoSe2 at different magnifications, (c) EDAX spectrum of CoSe2
Figure S2: (a-b) FESEM images of NiSe2 at different magnifications, (c) EDAX spectrum of
NiSe2
3
Figure S3: (a-b) FESEM images of MnSe2 at different magnifications, (c) EDAX spectrum of
MnSe2.
4
Figure S4: (a) Survey spectrum of NiSe2 , (b) Ni 2p, (c and f) Se 3d, (d) Survey spectrum of
CoSe2 and (e) Co 2p.
Figure S 5 : Raman spectra pattern of CoSe2 and NiSe2.
5-0.3 -0.2 -0.1 0.0 0.1 0.2 0.3 0.4
-0.003
-0.002
-0.001
0.000
0.001
0.002
0.003
Curr
ent (
A)
Potential (V)
2mV/s 5mV/s 10mV/s 20mV/s 40mV/s 80mV/s 100mV/s
(a)
0 50 100 150 200 250
-0.2
0.0
0.2
0.4
Pote
ntia
l (V)
Time (s)
0.2A/g 0.3A/g 0.5A/g 0.8A/g 1A/g 2A/g
(b)
Figure S6 : (a) CV curves CoSe2 at different scan rates and (b) GCD curves of CoSe2 at
different current densities
Figure S7 : (a) CV curves NiSe2 at different scan rates and (b) GCD curves of NiSe2 at different
current densities
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-0.3 -0.2 -0.1 0.0 0.1 0.2 0.3 0.4-2.0m
-1.0m
0.0
1.0m
2.0m
Curr
ent (
A)
Potential (V)
2mV/s 5mV/s 10mV/s 20mV/s 40mV/s 80mV/s 100mV/s
(a)
0 100 200 300 400 500 600
-0.2
0.0
0.2
0.4
Pote
ntia
l (V)
Time (s)
0.1A/g 0.2A/g 0.3A/g 0.5A/g 0.8A/g 1A/g 2A/g
(b)
-0.3 -0.2 -0.1 0.0 0.1 0.2 0.3
-400.0µ
-200.0µ
0.0
200.0µ
400.0µ
Curr
ent(
A)
Potential (V)
2mV/s 5mV/s 10mV/s 20mV/s 40mV/s 80mV/s 100mV/s
(a)
0 20 40 60 80 100 120 140
-0.2
0.0
0.2
Pote
ntia
l (V)
Time (s)
0.08A/g 0.1A/g 0.2A/g 0.3A/g 0.5A/g 0.8A/g 1A/g
(b)
Figure S8 : (a) CV curves MnSe2 at different scan rates and (b) GCD curves of MnSe2 at
different current densities
Table S1. Comparison of lattice parameters with the reported works.
Samples Lattice parameters (Å)a b c
CoSe2 4.88(4.850)7
5.81(5.827)7
3.64(3.628)7
NiSe2 5.94(5.960)8
5.94(5.960)8
5.94(5.960)8
MnSe2 6.28(6.417)9
6.28(6.417)9
6.28(6.417)9
Figure S9 : DFT optimized structure of (a) CoSe2 (101), (b) NiSe2 (200) (c) and MnSe2 (200).
Violet, red, pink and blue represent Co, Ni, Mn and Se respectively.
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Figure S10 : Ragone plot
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(b)
(c)
(a)
Figure S11. Charge density plots: (a) CoSe2, (b) NiSe2 (c) MnSe2. Violet, green, blue and red
color indicate Co, Ni, Mn and Se atom, respectively; yellow is the charge density iso-surfaces
with iso-value 0.08e.
Figure S12. XRD taken after electrochemical measurements: (a) CoSe2, (b) NiSe2 and (c)
MnSe2.
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