From lignin self assembly to nanoparticles nucleation and growth: A critical perspective

Recently, self-assembly processes operating in lignin have been the subject of intense research with the aim to prepare high-value, environmentally sustainable, nanomaterials for diverse material applications such as antimicrobial, antibacterial, UV-shielding, photonics etc. Lignin offers structural features that make these potential applications possible once well-tailored aggregates are synthesised. However, the intricate nature of lignin and the ensuing complexity of its aggregation behaviour, coupled with the plethora and diversity of techniques used, still requires systematic attempts to unify the scattered and at times contradictory data. This effort attempts to enumerate the various parameters affecting self-assembly phenomena of lignins by critically considering the science behind its solvation behaviour in organic solvents, in aqueous media, and its eventual self-assembly in forming nano-systems. Finally, knowledge gaps that cause present limitations and potential future efforts, are identified so as to arrive at a thorough comprehension of these phenomena.