Polyoxometalates (Jun 2024)

Rapid and highly sensitive detection of formaldehyde gas via a polyoxometalate–CuBi2O4 composite gas sensor

  • Pinfan Song,
  • Ying Yang,
  • Feng Li,
  • Hui Yu,
  • Xiangting Dong,
  • Tianqi Wang

Journal volume & issue
Vol. 3, no. 2
p. 9140053


Read online

Quick response and high sensitivity are equally important for the practical application of gas sensors. In this study, we introduced polyoxometalates (POMs) into a classical ternary metal oxide CuBi2O4 for the first time by convenient electrospinning and prepared a group of heater-type gas sensors by using CuBi2O4/PW12 composite nanofibers. The sensor performances to formaldehyde gas were explored. The results proved that the gas-sensing response of the CuBi2O4/PW12 (PW12 = H3PW12O40·xH2O) composite sensor to 100 ppm formaldehyde gas was increased to 6.68, which was 3.92 times greater than the sensing capacity of the pure CuBi2O4 sensor. Simultaneously, the sensor exhibited a highly rapid response/recovery time of only 1/2 s, which is significantly faster than performances of CuBi2O4 gas sensors reported in the past literature. The cause of the improvement of the sensing performance was assessed via mechanism study, and it was found that the introduction of PW12 into the sensor contributed to its enhanced performance. It was found that PW12, as an electron acceptor, increased carrier mobility and reduced electron–hole recombination, thus contributing to enhanced gas-sensing properties. Moreover, other gas-sensing parameters such as selectivity, humidity resistance, repeatability, long-term stability were investigated. Hence, this study contributed to the literature on the development of polyoxometalates-based gas sensors.