Synthesis of Li doped MgFe2O4 nanoparticles for humidity sensor applications

Abstract

Recently, there has been a greater emphasis on researching the potential use of ferrite nanoparticles as humidity-sensing materials. We report on the humidity-sensing properties of Mg1-yLiyFe2O4 (y = 0, 0.01, 0.03 and 0.05), which were synthesized using the solution combustion synthesis route. According to the XRD analysis, it was observed that both the unit cell volume and the crystallite size increased as the concentration of lithium-ion increased. The crystallite size was measured to be 17-22 nm, indicating the presence of nanomaterials. Moreover, the material exhibited a single phase with the Fd-3m space group, suggesting its structural integrity and uniformity. The FE-SEM images revealed that the porous nature of the material became more pronounced with higher concentrations of Li, indicating potential benefits for sensing applications. The synthesized powder demonstrated promising characteristics for use in humidity sensors. Specifically, it was noted that increasing the Li composition led to a notable increase in resistance, particularly significant for the Li = 0.05 concentration, which exhibited the highest average sensitivity. This suggests that Li doping at this concentration effectively enhances resistance, a crucial aspect for sensor functionality. The response and recovery times of thin film humidity sensors fabricated from these materials were determined to be 9 and 12 seconds, respectively. These times indicate rapid and efficient sensing capabilities, essential for real-time monitoring applications. Moreover, the newly discovered sensing material exhibited exceptional stability and reproducibility, further highlighting its potential for practical sensor applications. In summary, the synthesized materials show great promise for humidity sensor applications due to their enhanced sensitivity, rapid response and recovery times, as well as their stability and reproducibility. These findings open up avenues for the development of advanced sensing technologies with improved performance and reliability.