Electrochemical sensors based on amorphous carbon electrode: A review

[Display omitted] •DLC and CNx enable cost-effective sensing.•Doping expands detectable compounds.•Biofunctionalization is challenging. Amorphous carbon, including diamond-like carbon (DLC) and carbon nitride (CNx), has emerged as a highly promising electrode material for electrochemical sensor development, owing to its exceptional physicochemical and electrochemical properties. These include a wide potential window, minimal background currents, high tolerance to extreme potentials, and enhanced resistance to fouling compared to conventional carbon-based electrodes. A major advantage of these materials is their cost-efficient production methods and the flexibility to synthesize them on a variety of substrates, including metals and polymers. This review aims to provide a comprehensive and up-to-date overview of electrochemical sensors based on amorphous carbon, serving as both a reference and a resource for researchers interested in leveraging these materials. It highlights the unique positioning of amorphous carbon compared to conventional electrode materials, emphasizing its advantages and potential applications. The discussion encompasses the physicochemical, electrochemical, and structural properties of amorphous carbon, with a focus on the influence of various deposition processes. Additionally, the review delves into advanced strategies such as doping and surface treatments that further enhance the performance of amorphous carbon coatings. Lastly, it presents a detailed compilation of electrochemical sensors utilizing amorphous carbon as the electrode material, showcasing their capabilities and the breadth of their applications in sensor technology.