Laser-Engraved Boron-Doped Diamond for Copper Catalyzed Non-Enzymatic Glucose Sensing

Robust and high-performance electrochemical electrodes for non-enzymatic glucose sensing are in constant demand. Herein, a hierarchical nonenzymatic glucose sensing electrode on boron-doped diamond (BDD) is fabricated using high-speed laser engraving and pulsed electrodeposition of Cu nanostructures. The obtained electrode contains a densely packed Cu nanoflake (CuNF) array periodically decorated on the laser-engraved BDD. The hierarchical nanoarchitecture combines the d-band catalytic activity of the CuNFs with the low capacitive background current of the engraved BDD substrate, thus enabling fast, precise, and high signal-to-noise ratio detection of trace glucose. Outstanding performances that combine high sensitivity of 2119 µA cm –2 m m –1 , ultrafast response time of <1 s, and low detection limit of 0.2 × 10 −6 m are experimentally demonstrated. Furthermore, the electrode exhibits excellent cyclicality and anti-interference ability, and maintains 90% of its initial responsivity after being stored in air for >8 months, indicating great stability for practical usage.