From Planar to Patterned: Structured Boron‐Doped Diamond Electrodes for Electrochemical Sensing

Structured boron‐doped diamond (BDD) electrodes have evolved beyond planar interfaces into a promising platform for electrochemical sensing. By introducing deliberately engineered micro‐ and nanostructures, the electrode–electrolyte interface can be tailored to enhance analytical performance while preserving the excellent properties of BDD, including wide potential window, chemical robustness, and resistance to fouling. Although the first sensing studies on structured BDD appeared in the late 2000s and the field has expanded markedly since then, no review has yet focused specifically on structured BDD for sensing and electroanalysis. This mini‐review fills that gap by summarizing the reported top‐down and bottom‐up fabrication strategies and the resulting architectures, including nanowires, nanograss, porous films, and template‐derived three‐dimensional structures. Their applications are discussed across major analyte classes, from neurotransmitters and other biologically relevant small molecules to biomacromolecules and toxic heavy metal ions. Particular emphasis is placed on emerging structure–property–performance relationships, showing that the benefits of structuring cannot be explained by surface area increase alone, but arise from the interplay of morphology, accessibility, mass transport, and local surface chemistry. Current challenges and future directions are also outlined, especially with respect to reproducibility, scalability, and device integration.