Temperature coefficient of resistance improvement in La0.67Ca0.33MnO3 polycrystalline ceramics with vanadium addition

Perovskite manganites La 0.67 Ca 0.33 MnO 3 (LCMO) holds promising for infrared bolometer applications due to its large temperature coefficient of resistance (TCR) and low 1/ f noise. However, it remains challenging to obtain large TCR value at a wide temperature range, which inhibits its actual application. In this study, we compare the effects of sintering temperature (1200 °C ∼ 1450 °C), vanadium addition (0% and 5%), and vanadium addition route (sol-gel doping and solid-state composite) on the structure, morphology and electrical transport properties of LCMO. We found that the ceramics prepared with higher temperature possess larger grain size and higher density. Vanadium addition considerably increases the grain size as well as improves TCR value. Our findings provide an effective route to promote the infrared detect application of perovskite manganites.