Table 7 New detected peaks in FTIR spectra of some graphene samples after DES treatment with the expected matching functional groups
From: Functionalization of graphene using deep eutectic solvents
Graphene sample | New allocated peaks | Expected functional groups |
|---|---|---|
1 | 3356 | O–H (stretching)/asymmetric NH2 (stretching) |
1930 | CH2 (bending)/C=O | |
1362 | C–O–H (bending)/C–O (stretching), alcohol, ester, ether, carboxylic acid | |
1078 | C-C-O (asymmetric stretching) | |
506 | O-H (Out-of-plane bending)/C–H (bending) | |
3 | 3794 | O–H (stretching)/– OH (unbonded) |
2171 | sp3 hybridized C–H (stretching) | |
1980 | CH2 (bending) | |
1937 | sp3 hybridized C–H (stretching)/C–O (stretching), alcohol, ester, ether, carboxylic acid | |
1330 | O-H (In-plane bending)/N–H (bending) | |
1248 | C–O–H (bending)/C–O (stretching), alcohol, ester, ether, carboxylic acid | |
5 | 3322 | NH2 (symmetric/asymmetric stretching) |
3199 | O–H (stretching)/–CH2 (antisymmetric stretching) | |
1606 | 1° amide N–H scissoring band | |
1444 | C–N (stretching) | |
950 | C–N+ (symmetric stretching)/N–O (in-plane bond) | |
6 | 3209 | sp3 hybridized C–H (stretching) |
7 | 1100-1150 | C–O–H (bending)/C–O (stretching), alcohol, ester, ether, carboxylic acid |
8 | 531 (shoulder peak) | C–N+ (symmetric stretching) |
9 | 1240 | C–O–H (bending) |
2476 | N-H+ (stretching) of quaternary ammonium | |
12 | 1319 | C–O–H (bending) |
1255 | C–O–H (bending)/C–O (stretching), alcohol, ester, ether, carboxylic acid | |
13 | 2164 | =C-H and ring C=C (stretching) |
1323-1255 | C–O–H (bending)/C–O (stretching), alcohol, ester, ether, carboxylic acid | |
14 | 2661 | N-CH3 (symmetric stretching)/–CH2 (antisymmetric stretching) |
2203 | CH2 (bending)/–CH2 (symmetric stretching) | |
1323 | CO (stretching) + CCH (stretching) + ring of pyranose (antisymmetric stretching)/N–H (bending) | |
1255 | CO (stretching) + CCH (stretching) + ring of pyranose (antisymmetric stretching)/C–O (stretching), alcohol, ester, ether, carboxylic acid | |
15 | 3353 | O-H (stretching)/asymmetric NH2 stretch |
1930 | CH2 bond bending vibration/C–O (stretching), alcohol, ester, ether, carboxylic acid | |
1330 | CO (stretching) + CCH (stretching) + ring of pyranose (antisymmetric stretching) | |
1255 | CO (stretching) + CCH (stretching) + ring of pyranose (antisymmetric stretching)/C–O (stretching), alcohol, ester, ether, carboxylic acid | |
1078 | C–N+ (symmetric stretching) | |
479 | CCO (in-plane bending) + CCH (in-plane bending)/C–H (bending) | |
16 | 2161 | CH2 (bending)/– CH2 (symmetric stretching) |
1987 | CH (symmetric stretching) of C2/C–O (stretching) | |
873 (shoulder peak) | C–N+ (symmetric stretching) | |
503 (shoulder peak) | CH (in-plane bending) + CC (stretching)+ CC (in-plane bending) | |
17 | 2027 | CH2 (bending) |