Metal-Doped Porous Carbon-Hybrid Micro/Nanofibers: Design and Environmental Applications

Abstract

Metal-doped porous carbon-hybrid micro/nanofibers are emerging as advanced materials for sustainable environmental remediation because they combine porous carbon networks with chemically active metal sites. Recent research has focused on Fe-, Co-, Ni-, Mn-, Zn-, Ti-, and Bi-based carbon fiber hybrids, including electrospun carbon nanofibers, activated carbon fibers, metal organic framework (MOF)-derived porous fibers, metal oxide/carbon composites, layered double hydroxide (LDH)-modified carbon fibers, and metal nanoparticle-decorated fibrous membranes. These materials provide a high surface area, hierarchical porosity, tunable surface chemistry, good conductivity, and improved accessibility of active sites, making them suitable for water treatment, air purification, catalytic degradation, and environmental sensing. This chapter discusses recent progress in the design, synthesis, and application of these fiber-based composites. Key preparation methods include electrospinning, hydrothermal growth, in situ MOF formation, chemical vapor deposition, template-assisted carbonization, activation, and post-synthetic metal coordination. Their environmental applications include heavy-metal adsorption, dye and antibiotic removal, CO2 and SO2 capture, PM filtration, Fenton-like oxidation, photocatalysis, antimicrobial treatment, and electrochemical or fluorescence sensing. Additionally, the chapter outlines key mechanisms including electrostatic attraction, ion exchange, surface complexation, precipitation, π-π interactions, hydrogen bonding, redox conversion, radical generation, and charge transfer. Regeneration, stability, secondary pollution, scalability, and sustainability are also considered for practical application.