NiTiO3/Bi2O3/MoS2 double Z-type heterojunction catalysts realize dual-function applications of photocatalytic fuel cells and lactic acid sensing

Sensors in intelligent monitoring and personal healthcare generally face power supply problems, such as cycle charging, regular maintenance, and battery replacement, which greatly limit the applications of sensing devices. Self-powered sensing system with a visible-light-driven photo-fuel cell (PFC) exhibits the advantage of not requiring any external power source for the chemical sensing of analytes. In this work, an enzyme-free PFC self-powered sensing platform was established for sensing sweat lactate using photoelectric conversion technology. A NiTiO 3 /Bi 2 O 3 /MoS 2 double Z-type heterojunction system was prepared by electrostatic interaction and self-assembly as the anode of the PFC. NiTiO 3 , Bi 2 O 3 and MoS 2 formed a double Z-type heterojunction system accelerated the electron transfer and improved the light absorption and photocatalytic efficiency, which in turn improved the perception of LA. In addition. lactic acid sensing experiments showed that the prepared non-enzymatic photoelectrochemical sensors had good detection performance. The assay results showed that the prepared biosensor has a wide detection range (30 μM-5 mM), low detection limit (6 μM), high selectivity(8μA μM −1 cm −2 ) and long-term stability. These assay results demonstrate its potential for applications in fields such as biomedicine and drug analysis.