Supporting Information

Highly Stable Nitrogen-Doped Carbon Nanotubes Derived from Carbon

Dots and Metal-Organic Frameworks Toward Excellent Efficient

Electrocatalyst for Oxygen Reduction Reaction

Wen-Jun Niu*a,b, Ya-Ping Wanga,b, Jin-Zhong Hea,b, Wen-Wu Liua,b, Mao-Cheng Liua,b, Dan

Shanc, Ling Leed, Yu-Lun Chueh*d,e,f

aKey Laboratory of Advanced Processing and Recycling of Non-ferrous Metals, Lanzhou

University of Technology, Lanzhou 730050, PR China.

bSchool of Materials Science and Engineering, Lanzhou University of Technology, Lanzhou

730050, PR China.

cSchool of Environmental and Biological Engineering, Nanjing University of Science and

Technology, Nanjing 210094, PR China..

dDepartment of Materials Science and Engineering, National Tsing Hua University, Hsinchu,

30013, Taiwan, ROC.

eDepartment of Physics, National Sun Yat-Sen University, Kaohsiung, 80424, Taiwan, ROC.

fFrontier Research Center on Fundamental and Applied Sciences of Matters, National Tsing

Hua University, Hsinchu 30013, Taiwan, ROC.

* E-mail Address: niuwenjun0509@163.com and ylchueh@mx.nthu.edu.tw

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Figure S1 (A) TEM and (B) HR-TEM images of the N-Cdots.

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Figure S2 (A) Low-resolution and (B) high-resolution SEM images of the ZIF-67.

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Figure S3 XRD results of (A) N-Cdots and (B) ZIF-67, respectively.

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Figure S4 CVs for (A) bare GCE, (B) N-Cdots, (C) Co-N-C nanohybrids and (D) Pt/C electrodes in N2-saturated (curve a) and O2-saturated (curve b) 0.1 M KOH at a scan rate of 10 mV s-1.

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Figure S5 LSVs for (A) N-Cdots, (C) Co-C-N, and (E) Pt/C electrodes in the O2-saturated 0.1 M KOH solution at a series of rotation rates from 400 to 2025 rpm with a scan rate of 5 mV s-1. Koutecky−Levich plots (j−1 versus ω−1/2) of (B) N-Cdots, (D) Co-N-C, and (F) Pt/C electrodes at different potentials.

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Table S1 A summary of various electrocatalysts for ORR performance.

Onset Half-wave CV peak ElectronElectrocatalysts Potential Potential potential Transfer

(V) (V) (V) NumberN-CNTs 0.88 0.82 0.80 3.92

NCNTFs[1] 0.97 0.87 0.87 3.97

N-CNTs-650[2] 0.94 0.85 0.87 3.94

CNT/grapheme hybrid[3] 0.89 0.76 0.75 4.0

Defective grapheme[4] 0.91 0.76 — 3.87

NC@Co-NGC DSNC[5] 0.92 0.82 0.81 4.0

Co3O4/N-rmGO[6] 0.88 0.79 0.83 3.9

ZIF-67-900[7] 0.91 0.85 — 4.0

Co-NC[8] 0.92 0.83 — 3.72

P-Z8-Te-1000[9] 0.88 0.79 — 4.0

Co,N-CNF[10] 0.88 0.81 0.77 3.8

Co/N-C-800[11] 0.83 — 0.73 3.94

[CoN4]3/C[12] 0.82 — 0.70 3.7

Co-N-GN[13] 0.86 0.80 0.78 3.7

Co/N/rGO(NH3)[14] 0.85 0.81 0.72 3.9

CoMn2O4 nanotubes[15] 0.89 0.72 0.81 3.6

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