Supporting Information

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Supporting Information

Direct Growth of Oxygen Vacancy Enriched Co

3

O

4

Nanosheets on

Carbon Nanotubes for High-Performance Supercapacitors

Xiaoyu Zhang, Ge Ma, Lingling Shui, Guofu Zhou, Xin Wang *

South China Academy of Advanced Optoelectronics & International Academy of Optoelectronics at

Zhaoqing, South China Normal University, Guangdong, 510631, PR China.

* Corresponding author

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Figures

100 nm 100 nm 100 nm 100 nm

a

b

c

d

Figure S1. SEM images of (a) Co3O4-NSs/CNTs-3% nanocomposites, (b) Co3O4-NSs/CNTs-10% nanocomposites, (c) Co3O4-NSs and (d) Co3O4-NPs/CNTs-5% nanocomposites.

Figure S2. XRD patterns of Co3O4-NSs/CNTs-3% and Co3O4-NSs/CNTs-10%.

Figure S3. (a) Survey XPS spectra of Co3O4-NSs/CNTs-5% nanocomposites and Co3O4-NSs and (b) O 1s XPS spectrum of Co₃O₄-NSs (c) Co 2p XPS spectrum of Co₃O₄-NPs/CNTs-5% nanocomposites, and (d) N₂ isotherm profiles and pore size distribution of Co3O4-NSs/CNTs-3% nanocomposites and Co3O4-NSs/CNTs-10% nanocomposites.

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0 500 1000 1500 2000 2500 3000 50 60 70 80 90 100 110 120 103.6% 95% Co3O4-NSs Co3O4-NSs/CNTs-5% C ap ac it an ce r et en ti on ( % ) Cycle number 200 nm

a

_b

Figure S4. (a) GCD cycling performance of Co3O4-NSs/CNTs-5% and Co3O4-NSs at the current density of 30 A g-1_{after 3000 cycles, (b) the SEM image of Co}

3O4-NSs/CNTs-5% after cycling performance.

Figure S5. (a) CV curves of individual positive and negative electrodes measured in a three-electrode system at 5 mV s-1_{, (b) the specific capacitance of ASC at different densities (c) CV curves at different scan rates from 0.2 to 2} mV s-1_{, and (d) cycling performance of ASC, respectively.}

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Tables

Table S1

Performance comparison between Co

3

O

4

-NSs/CNTs-5% nanocomposites with previously

reported Co

3

O

4

-based materials

Sample

Speciﬁc

capacitance [F g-1_]

Cycling stability Electrolyte Ref.

Co3O4-NSs/ CNTs-5% 1280.4 (1 A g-1) 112.5%(10000 cycles) 6 M KOH This work

Co3O4 nanosheet 502.4 (1 A g-1) 77%(5000 cycles) 1 M KOH 20201

Co3O4-incorporated multichannel carbon nanofiber 821 (1 A g -1₎ _{92.1%(5000 cycles)} _{6 M KOH} ₂₀₂₀2 three-dimensional porous carbon/Co3O4 423 (1 A g-1₎ _{83%(2000 cycles)} _{3 M KOH} ₂₀₂₀3

Co3O4@Carbon cloth 806 (1 A g-1) 90.8%(8000 cycles) 2 M KOH 20204

Co3O4-NiO/graphene foam 776 (1 A g-1) 86%(5000 cycles) 2 M KOH 20195

core-shell Co3O4 nanospheres 837.7 (1 A g-1) 87%(2000 cycles) 6 M KOH 20196

Co3O4/Carboxymethyl cellulose 662.2 (1 A g-1) 90%(5000 cycles) 2 M KOH 20197

Co3O4@NiO nanosheet 681 (1 A g-1) 102%(6000 cycles) 2 M KOH 20188

Co3O4 nanoparticles/graphene 978.1 (1 A g-1) 93.7%(20000 cycles) 2 M KOH 20189

Co3O4-laser-scribed graphene 986 (1 A g-1) 113.1%(10000 cycles) 6 M KOH 201810

Co3O4/nitrogen-doped carbon hollow

spheres 581 (1 A g

-1₎ _{95.2%(5000 cycles)} _{2 M KOH} ₂₀₁₈11

Co3O4 hollow frame 770 (1 A g-1) 95.8%(5000 cycles) 1 M KOH 201812

Co-Co3O4@CNT incorporated

nitrogen-doped carbon 823.4 (1 A g

-1₎ _{93.6%(10000 cycles)} _{6 M KOH} ₂₀₁₈13

AuNP/nano-Co3O4 nanoflower 657 (1 A g-1) 83.1%(15000 cycles) 2 M KOH 201714

Co/Co3O4@carbon matrix 615 (1 A g-1) 70%(5000 cycles) 1 M KOH 201715

NiO@Co3O4@MnO2 particles 865 (1 A g-1) 91.3%(1000 cycles) 1 M KOH 201716

Co3O4-nanocube/Co(OH)2-nanosheet 1164 (1 A g-1) 97.4%(5000 cycles) 3 M KOH 201717

MOF derived Co3O4 nanosheets 1121 (1 A g-1) 98.2%(6000 cycles) 6 M KOH 201718

Carbonized wing-Co3O4 nanopillar

array 940.9 (1 A g

-1₎ _{94.5%(2000 cycles)} _{6 M KOH} ₂₀₁₆19

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Table S2

Comparison of tow-electrode performance between the prepared sample and the materials

in the literature

ASCs Speciﬁc capacitance (F

g-1₎

The maximum Energy density (Wh kg−1₎

Maximum Power density (W kg−1₎ Ref.

Co3O4-NSs/CNTs//rGO 104.5 (0.5 A g-1) 37.2 7620 This work

3D-Co3O4/C@hollow carbon

nanofibers//Nitrogen-doped graphene hydrogel 102.4 (1A g-1₎ _36.6 _4053.7 ₂₀₂₀21 Co3O4-60//CC 81 (1 A g-1) 25.3 7500 20204 Co3O4//Graphene 101.4 (1 A g-1) 35.8 7805.6 20196 Co3O4/NHCS||AC 34.5 3807 201811 GCCO-2//rGO 92 32.7 6400 201822 NiCo2O4//AC 68.7 (1 A g-1) 21.5 4500 201823 rGO-MgCo2O4//AC 31 2000 201724 Co3O4/Ndoped carbon

aerogel||N-doped carbon aerogel 107(0.5 A g

-1₎ _33.43 ₄₅₀₀ ₂₀₁₆25

NiCo2O4/Cu-based//activated graphene 48(0.5 A g-1) 12.6 4950 201526

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