Facile synthesis of novel YbFeO3–BiFeO3 composite for highly sensitive ppb-level acetone sensing at low temperature

High sensitivity and low detection limit are crucial parameters in evaluating the performance of gas sensors, particularly in detecting trace amounts of acetone gas in human respiration for diabetes monitoring purposes. In this study, a composite of YbFeO 3 –BiFeO 3 (YFO–BFO) was prepared using a facile method involving the calcination of a mixture of Yb 2 O 3 and BiFeO 3 , followed by acid treatment. It is revealed that the introduction of YbFeO 3 significantly improves the acetone gas sensitivity and reduces the operating temperature. At an optimized operating temperature of 200 °C, the response of YFO–BFO to 10 ppm acetone reaches 32.6, which is 16.6 times higher than that of BiFeO 3 at the optimized operating temperature of 280 °C. Moreover, the response to 400 ppb of acetone still has 7 even at the low temperature of 160 °C. YFO–BFO also exhibits a low limit of detection (25 ppb), good selectivity and stability. The excellent gas-sensing performance of YFO–BFO is mainly attributed to the formation of a p-p heterojunction and the increased Fe 2+ /Fe 3+ redox pairs. This work offers a novel approach for enhancing the acetone sensing properties of BiFeO 3 -based gas sensors, which may lead to the advancement of acetone sensors for the diagnosis of diabetes.