G-C3N4/In2O3 composite for effective formaldehyde detection

This paper reports a new type of high-performance formaldehyde gas sensor using g-C3N4 nanosheets to modify the surface of In2O3 nanospheres as the sensing material. SEM and TEM results showed that g-C3N4 nanosheets were uniformly distributed on the surface of In2O3. The samples were characterized by XPS, and it was found that both oxygen defects (O-v) and chemically adsorbed oxygen (O-c) in the composite material were increased. The sensor performance under different loadings of g-C3N4 was systematically studied. Especially for 12 wt% loading the response of the sensor material with to 100 ppm formaldehyde reached 1405, which was 2 times bigger than that of pure In2O3. Importantly, it also had a low operating temperature of 119?C and a short response time of 1 s. The enhancement of sensing performance could be attributed to the realization of rapid electron transfer and the exposure of high-density active center by constructing a unique n-n heterostructure. This research provides an effective method for preparing a formaldehyde sensor with fast response, high sensitivity and low power consumption.

Automated summary

This paper reports a new type of high-performance formaldehyde gas sensor using g-C3N4 nanosheets to modify the surface of In2O3 nanospheres as the sensing material. The sensor showed a 2-fold response increase compared to pure In2O3 when loaded with 12 wt% g-C3N4, with low operating temperature and short response time.