TY - JOUR
T1 - Selected Kraft lignin fractions as precursor for carbon foam
T2 - Structure-performance correlation and electrochemical applications
AU - Rodrigues, Jéssica S.
AU - de Freitas, Amanda De S.M.
AU - Maciel, Cristiane C.
AU - Guizani, Chamseddine
AU - Rigo, Davide
AU - Ferreira, Marystela
AU - Hummel, Michael
AU - Balakshin, Mikhail
AU - Botaro, Vagner R.
PY - 2023/6/15
Y1 - 2023/6/15
N2 - The rapid exhaustion of fossil fuels brings to the fore the need to search for energy efficient strategies. The conversion of lignin into advanced functional carbon-based materials is considered one of the most promising solutions for environmental protection and the use of renewable resources. This study analyzed the structure-performance correlation of carbon foams (CF) when lignin-phenol-formaldehyde (LPF) resins produced with different fractions of kraft lignin (KL) were employed as carbon source, and polyurethane foam (PU) as sacrificial mold. The lignin fractions employed were KL, fraction of KL insoluble in ethyl acetate (LFIns) and fraction of KL soluble in ethyl acetate (LFSol). The produced CFs were characterized by thermogravimetric analysis (TGA), X-ray diffractometry (XRD), Raman spectroscopy, 2D HSQC Nuclear magnetic resonance (NMR) analysis, scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET), and electrochemical measurements. The results showed that when LFSol was employed as a partial substitute for phenol in LPF resin synthesis, the final performance of the produced CF was infinitely higher. The improved solubility parameters of LFSol along with the higher S/G ratio and β-O-4/α-OH content after fractionation were the key to produce CF with better carbon yields (54 %). The electrochemical measurements showed that LFSol presented the highest current density (2.11 × 10−4 mA.cm−2) and the lowest value of resistance to charge transfer (0.26 KΩ) in relation to the other samples, indicating that the process of electron transfer was faster in the sensor produced with LFSol. LFSol's potential for application as an electrochemical sensor was tested as a proof of concept and demonstrated excellent selectivity for the detection of hydroquinone in water.
AB - The rapid exhaustion of fossil fuels brings to the fore the need to search for energy efficient strategies. The conversion of lignin into advanced functional carbon-based materials is considered one of the most promising solutions for environmental protection and the use of renewable resources. This study analyzed the structure-performance correlation of carbon foams (CF) when lignin-phenol-formaldehyde (LPF) resins produced with different fractions of kraft lignin (KL) were employed as carbon source, and polyurethane foam (PU) as sacrificial mold. The lignin fractions employed were KL, fraction of KL insoluble in ethyl acetate (LFIns) and fraction of KL soluble in ethyl acetate (LFSol). The produced CFs were characterized by thermogravimetric analysis (TGA), X-ray diffractometry (XRD), Raman spectroscopy, 2D HSQC Nuclear magnetic resonance (NMR) analysis, scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET), and electrochemical measurements. The results showed that when LFSol was employed as a partial substitute for phenol in LPF resin synthesis, the final performance of the produced CF was infinitely higher. The improved solubility parameters of LFSol along with the higher S/G ratio and β-O-4/α-OH content after fractionation were the key to produce CF with better carbon yields (54 %). The electrochemical measurements showed that LFSol presented the highest current density (2.11 × 10−4 mA.cm−2) and the lowest value of resistance to charge transfer (0.26 KΩ) in relation to the other samples, indicating that the process of electron transfer was faster in the sensor produced with LFSol. LFSol's potential for application as an electrochemical sensor was tested as a proof of concept and demonstrated excellent selectivity for the detection of hydroquinone in water.
KW - Carbon foams
KW - Kraft lignin
KW - Lignin fractions
KW - Thermal decomposition. Electrochemical applications
UR - http://www.scopus.com/inward/record.url?scp=85152719361&partnerID=8YFLogxK
U2 - 10.1016/j.ijbiomac.2023.124460
DO - 10.1016/j.ijbiomac.2023.124460
M3 - Article
AN - SCOPUS:85152719361
SN - 0141-8130
VL - 240
JO - International Journal of Biological Macromolecules
JF - International Journal of Biological Macromolecules
M1 - 124460
ER -
