CVD Graphene on Iron, Iron Alloys, and Nanoparticles: A Review of Its Growth, Characterization, Applications, and Challenges
Graphene's exceptional electrical, thermal, mechanical, and chemical properties render it promising for electronics, energy storage, protective coatings, catalysis, and environmental remediation. However, large-scale adoption is hindered by high synthesis costs, process complexities, and integration issues. Among production methods, chemical vapor deposition (CVD) on metals is the most scalable, with copper widely used due to its low carbon solubility and excellent monolayer control. Yet, Cu substrates are costly ($8–10/kg), transfer steps introduce defects, and the resulting graphene is poorly matched to structural components. Iron-based substrates offer an attractive alternative, providing much lower material cost, direct compatibility with steel infrastructure, reduced growth temperatures, and intrinsic functionalities such as magnetism and catalytic activity, enabling new applications. This review analyzes graphene growth on pure iron, iron alloys, and iron-based nanoparticles, focusing on growth mechanisms, substrate engineering, and characterization approaches tailored to challenges like carbide formation. Applications including corrosion-resistant coatings, electronics, energy storage, catalysis, water treatment, and electromagnetic shielding are considered. Despite the limitation of high carbon solubility, iron can be exploited for controlled multilayer formation useful for barrier and energy applications, while alloying and process control enable tunable monolayer or few-layer films, making iron-based CVD graphene a versatile, cost-effective platform.