Chitin‐Derived Carbon‐Metal Functional Materials

ABSTRACT

Biomass‐derived carbon materials have emerged as sustainable alternatives to petroleum‐derived adsorbents for environmental remediation applications. Among biomass feedstocks, chitin offers advantages due to its abundance as seafood‐processing waste and its intrinsic nitrogen content, which can facilitate the formation of nitrogen‐doped carbon materials during thermal conversion. Here, we investigate the evolution of iron and carbon speciation in an iron‐loaded chitin system across a broad pyrolysis temperature regime. Spectroscopic analysis demonstrates that Fe ³⁺ species interact with chitin functional groups, accelerating decomposition during pyrolysis. Structural characterization shows that this accelerated decomposition is accompanied by earlier loss of chitin crystallinity and rapid formation of carbonaceous species. At higher temperature ranges, iron oxide nanoparticles nucleate and subsequently undergo reduction through interactions with biopolymer decomposition products, producing iron carbide nanoparticles surrounded by graphitic carbon domains. Despite exhibiting lower residual nitrogen content than iron‐free pyrolyzed chitin, iron‐loaded pyrolyzed chitin materials demonstrate substantially enhanced methylene blue adsorption kinetics, with pseudo‐second‐order initial adsorption rates approaching an order of magnitude greater than their iron‐free counterparts. The improved adsorption behavior is attributed to increased surface area. These findings provide design principles for sustainable carbon‐based materials derived from renewable feedstocks for water purification applications and beyond.