File Name : fig. s1.tif

Caption : fig. s1. sem images of (a) cmc. (b) n-cmc-1:5. (c) n-cmc- 1:1. (d) n-cmc-4:1.

File Name : fig. s2.tif

Caption : fig. s2. raman spectra of cmc, n-cmc-1:5, n-cmc-1:1, and n-cmc-4:1, with id/ig ratios for each sample indicated.

File Name : fig. s3.tif

Caption :  fig. s3. high-resolution o 1s xps spectra of (a) cmc, (b) n-cmc-1:5, (c) n-cmc-1:1 and (d) n-cmc-4:1, respectively.

File Name : fig. s4.tif

Caption : fig. s4. the relative content change of various nitrogen species of the n-cmcs.

File Name : fig. s5.tif

Caption : fig. s5. (a) xps survey scan of n-cmc-1:6, (b) high-resolution n1s xps spectrogram of n-cmc-1:6.

File Name : fig. s6.tif

Caption : fig. s6. (a) linear sweep voltammetry of n-cmc-1:6 with the disk current density, ring current, (b) h2o2 selectivity and electron transfer numbers (n) of n-cmc-1:6.

File Name : fig. s7.tif

Caption : fig. s7. (a, c) cv for cmc and n-cmc-1:5 modified electrodes in the double layer region at scan rates of 5, 10, 15, 20, and 25 mv s-1 in 0.1 m koh aqueous electrolyte. (b, d) current (taken at the potential of 0 v vs. ag/agcl) as a function of scan rate derived from (a, c), respectively.

File Name : fig. s8.tif

Caption :  fig. s8. tafel plots for cmc, n-cmc-1:5, n-cmc-1:1 and n-cmc-4:1 for orr in 0.1 m koh.

File Name : fig. s9.tif

Caption : fig. s9. cv cycling stability performance of n-cmc-1:5 in 0.1 m koh.