Iron carbide (Fe₃C) is a ceramic magnetic material with high potential for applications in different fields, including catalysis, medicine imaging, coatings, and sensors. Despite its interesting properties, it is still somehow largely unexplored, probably due to challenging synthetic conditions. In this contribution, we present a sol-gel-based method that allows preparing different Fe₃C@C nanocomposites with tailored properties for specific applications, in particular, we have focused on and discussed potential uses for adsorption of noxious gas and waste removal. Nanocomposites were prepared using readily available and “green” sources, such as urea, simple and complex sugars, and chitosan. The nanocomposite prepared from chitosan was found to be more efficient for CO₂ uptake, while the sample synthetized from cellulose had optimal capability for dye absorption and waste oil removal from water.

In the range of biomass valorisation, hydroconversion of levulinic acid (one of the products of the hydrolysis of lignocellulosic biomass) was tested for the first time using nanosized Ni₃N and Ni⁰catalysts, with very promising results alongside high stability.