Graphene synthesis: A reactor-oriented review of conventional and emerging production methods

Abstract

Graphene's unparalleled electrical, mechanical, and thermal properties have positioned it as a transformative material across diverse sectors, including electronics, energy storage, biomedicine, and environmental remediation. However, scalable, cost-effective, and high-quality production remains a critical challenge. This review presents a comprehensive, reactor-oriented analysis of both conventional and emerging graphene synthesis methods, categorized into top-down and bottom-up approaches. Special emphasis is placed on the role of reactor configurations in determining product quality, layer control, scalability, and economic viability. Key synthesis techniques explored include chemical vapor deposition (CVD), epitaxial growth, electrochemical exfoliation, ultrasonic-assisted methods, microwave reactors, combustion synthesis, and plasma-enhanced processes. By evaluating reactor types such as tube furnaces, microwave plasmas, electrochemical cells, and ultrasonic flow systems, this paper highlights how reactor design influences growth kinetics, defect density, throughput, and energy efficiency. Through comparative analysis and detailed case studies, the review offers critical insights for optimizing reactor systems to bridge the gap between laboratory-scale research and industrial-scale graphene production. The study ultimately provides a strategic framework for engineers, chemists, and technologists aiming to advance the commercial viability of graphene through tailored reactor-based synthesis.