Ion-Beam-Engineered ReS ₂ Nanosheets for Uric Acid Sensing

Advancing the fundamental understanding and functional enhancement of two-dimensional (2D) materials is critical for the development of next-generation biosensors. In this work, we demonstrate an approach to modulate the physicochemical and electrochemical properties of ReS2 nanosheets through controlled low-energy nitrogen ion irradiation. By irradiating ReS2 nanosheets and depositing on screen-printed carbon electrodes at fluences of 1 × 1016 and 3 × 1016 ions/cm2, we achieved precise defect engineering and surface tuning, as revealed by a relevant characterization technique including FESEM, TEM, XRD, Raman spectroscopy, XPS, and UV–Vis spectroscopy. Monte Carlo simulations provided mechanistic insights into ion–solid interactions and defect formation, while wettability studies confirmed the significant modulation of surface energy. Electrochemical analyses revealed that ion-beam-treated ReS2 exhibits markedly enhanced electrocatalytic activity, enabling sensitive and selective uric acid detection in physiological conditions (PBS, pH 7.4) with a broad linear range of concentrations and a detection limit of about 380 μM. First-principles density functional theory calculations elucidated the underlying interaction mechanisms, highlighting improved uric acid adsorption and charge transfer dynamics on irradiated ReS2. This study not only provides a tunable platform to tailor 2D material properties via ion irradiation but also demonstrates its practical applicability in nonenzymatic electrochemical biosensing. These findings lay the groundwork for scalable, defect-engineered sensing technologies with potential across biomedical diagnostics and environmental monitoring.