Pore-edge high active sites of 2D WO nanosheets enhancing acetone sensing performance.

The precise and timely detection of acetone is crucial for ensuring industrial production safety and for clinical diagnosis of diabetes. Therefore, developing acetone sensors with high performance is increasingly important. This work successfully introduced nano-scale holes into two-dimensional (2D) WO nanosheets by topological transformation and in-situ oxidation. The porous 2D WO nanosheets exhibit a response value of 66.29 to 10 ppm acetone gas, which is 10.8 times higher than that of commercial WO. Additionally, the detection limit is as low as 40 ppb. The introduction of pores provides more channels for the rapid diffusion and adsorption of acetone molecules. At the same time, density functional theory (DFT) calculations confirm that the W atoms exposed at the edge of the pores have higher charge activity and adsorption capacity, which provides more edge active sites for the adsorption of acetone molecules. This work proves the feasibility of the introduction of holes to improve the gas sensing performance of metal oxide semiconductors. This study offers a new approach to developing porous metal oxide semiconductor (MOS) sensors.