Hierarchically Structured P-Doped MoS2/MoO2 Ultrathin Nanosheets on N-Doped Carbon Hemispheres for Sensitive Dopamine Detection

Dopamine (DA) is a key neurotransmitter in the central nervous system, and abnormal concentrations are associated with a variety of diseases. In this study, a novel electrochemical sensor is constructed based on ultrathin P-doped MoS₂/MoO₂ nanosheets supported on bowl-shaped N-doped carbon hemispheres (N-BCH@P-MoS₂/MoO₂). The unique hierarchical structure combines the high specific surface area of N-BCH with the enhanced electrocatalytic activity of P-doped MoS₂/MoO₂, resulting in significant improvements in the performance for DA detection. The electronic structure of the catalyst is further modulated by the codoping of N and P, which increases the electrical conductivity and the number of active centers. The results show that the N-BCH@P-MoS₂/MoO₂ exhibits excellent sensitivity and selectivity for DA detection, capable of achieving a detection limit as low as 0.12 μM within a broad concentration range (3-100 μM) (S/N = 3). Furthermore, electrocatalysts have been employed in the detection of DA in human serum, indicating significant promise for clinical diagnosis.