CeO2复合调控氧空位与电子结构增强Co3O4纳米棒氢传感性能OA

Hydrogen,as a clean energy carrier,plays a crucial strategic role in the low-carbon transition.However,its wide explosive limits and low ignition energy pose significant safety hazards to the secure utilization of hydrogen energy.A CeO2-Co3O4 composite hydrogen-sensitive material with a nanorod structure is successfully synthesized via hydrothermal synthesis and annealing treatment,effectively addressing the key issues of conventional metal oxide semiconductor hydrogen sensors,such as high operating temperature and sluggish response/recovery.The results show that the introduction of CeO2 induces lattice distortion at the octahedral sites of Co3O4.XPS further reveals that after CeO2 incorporation,the surface concentrations of oxygen vacancies and adsorbed oxygen increase,and the Co 2p peaks shift toward higher binding energy,confirming that CeO2 effectively modulates the surface chemical states and the local electronic structure of Co.The hydrogen sensing performance test results indicate that the composite material achieves a response value of 8.18 toward 500×10-6 H2(volurne fraction)at 150℃,which is approximately 2.2 times higher than that of pristine Co3O4.Its response and recovery times are shortened to 102 s and 33 s,respectively,and the detection limit is as low as 1×10-6.In addition,the response value exhibits a good linear relationship with the H2 concentration.The performance enhancement mechanism can be attributed to the synergistic increase in oxygen vacancies and adsorbed oxygen species induced by CeO2 compositing,which promotes surface activation of O2,and to the modulation of the Co electronic structure that accelerates charge transfer.This work provides a new strategy with a simple preparation process and cost-effectiveness for the design of high-performance hydrogen-sensitive materials.