High sensitivity potentiometric hydrogen sensor based on ZnFe2O4 electrode

Hydrogen is currently considered to be the best clean energy to replace fossil fuels, so hydrogen leak detection is crucial. The current research field of hydrogen sensors focuses on the discovery and optimization of sensitive materials. ZnFe2O4 powder is prepared by the sol-gel method and sintered at different temperatures. The effects of sintering temperature on electrode morphology and hydrogen sensing performance are investigated. The sensitivity reaches a maximum value of -101.32 mV/decade at the sintering temperature of 1100 degrees C. The sensor has different sensing performance at different operating temperatures. It has the best response value and sensitivity at 450 degrees C, and the best response/recovery rate and response curve stability at 550 degrees C. The sensor responds and recovers in seconds. The material has good H-2 selectivity and is suitable for potentiometric hydrogen sensors. CO, NH3, and CH4 have less effect on the response signal and exhibit good long-term stability.