Metal-Free Carbon Electrocatalysts for Renewable Energy and Environmental Sustainability: Mini Review
Keywords:
Metal-free electrocatalysts, carbon materials, renewable energy, HER, OER, ORR, environmental applicationsAbstract
The increasing demand for clean energy and environmental protection has created a need for efficient, low-cost, and sustainable electrocatalysts. Metal-based electrocatalysts show excellent catalytic activity, but their high cost, limited availability, and possible environmental concerns have encouraged researchers to develop metal-free alternatives. Metal-free carbon electrocatalysts are promising materials because of their good electrical conductivity, large surface area, chemical stability, and tunable structure. Their catalytic properties can be improved by introducing heteroatoms such as Nitrogen(N), Sulphur(S), Phosphorus(P), and Boron(B) and by creating defects and porous structures. These materials have attracted significant attention for renewable energy conversion reactions such as the hydrogen evolution reaction (HER), oxygen evolution reaction (OER), and oxygen reduction reaction (ORR). They are also useful in environmental applications, including wastewater treatment, pollutant removal, nitrate reduction, and carbon dioxide conversion. This review discusses the types, preparation methods, catalytic mechanisms, energy applications, environmental applications, challenges, and future prospects of metal-free carbon electrocatalysts.
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Copyright (c) 2026 Lavanya Kakinada, Veerendra Yadla (Author)
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