RESUMEN
Trace hydrogen detection plays an important role in the safety detection of lithium-ion batteries (LIBs) due to the generation and leakage of trace hydrogen in the early stage of LIBs damage. In this work, an amperometric hydrogen sensor based on solid polymer electrolyte was reported. The sandwich device structure was realized, which could directly diffuse the gas from both sides to the three-phase interface (gas/electrode/electrolyte) to participate in the reaction through the optimal design of the gas diffusion path. Then, platinum nanoparticles (Pt-NPs) were loaded on the metal foam by electroplating, and the porous electrode was filled with solid polymer electrolyte. A sensor with high specific surface area, high catalytic activity, and high sensitivity was obtained. Finally, the hydrogen oxidation reaction (HOR) mechanism of the platinum-loaded (Pt-loaded) titanium foam (Ti foam) electrode under both anaerobic and aerobic conditions was verified, and the properties of the sensor was evaluated. The hydrogen sensor with a "sandwich" structure has the advantages of high sensitivity, good stability, low detection limit and low cost, which provides a technical solution for the safety and real-time monitoring of LIBs.