Tailoring ammonia gas sensing performance of La3+-doped copper cadmium ferrite nanostructures

Lanthanum-doped copper-cadmium ferrite (La-CCF) nanocrystallite pallet sensors are synthesized using a sol-gel auto-combustion method and envisaged in ammonia gas sensing applications. The structure and morphology measurements of the La-CCF sensors are investigated by X-ray diffraction (XRD) pattern and scanning electron microscopy images. The single tetragonal spinel phase is confirmed from X-ray diffraction analysis. A secondary phase of LaO3 is observed when La doping level is >= 0.1 observed. The surface appearance of the La-CCF sensor changes from irregular polished course to irregular elevation type crystallites on La addition. The room-temperature gas sensing measurements suggest a better selectivity and sensitivity of La-CCF sensors for ammonia gas among several tested target gases. The sensing performance increases with La3+-doping level from x = 0.0 to 0.1 due to lattice defect introduced by a large sized La ion substitution.