Boosting the thermal conductivity of CNF-based composites by cross-linked lignin nanoparticle and BN-OH: Dual construction of 3D thermally conductive pathways

From plentiful and biocompatible materials still attracts much attention because of their great potential value in sensors and imaging. In this study, a highly fluorescent and super biocompatible N-doped carbon quantum dots derived from green precursor of aminated alkali lignin has been synthesized for cellular imaging. The amine-rich lignin carbon quantum dots (AL-CQDs) was firstly synthesized by introduction of secondary amine groups into lignin backbones via both Mannich and Machael addition reaction. The resulted AL-CQDs within the range of 4-10 nm exhibited excitation-dependent and pH-stable fluorescence properties and was employed for the detection of irons with a wide range from 100 nM to 1 mM and a low detection limit of 8 nM, in which the Fe3+ ions could be captured by the amine groups of the AL-CQDs to form an absorbent complex, resulting in a significant fluorescence quenching.