3D radial Co3O4 nanorod cluster derived from cobalt-based layered hydroxide metal salt for enhanced trace acetone detection

One-dimensional cobalt oxide (Co3O4) exhibits great potential in gas sensing, but the application is severely hindered because of the agglomeration or close packing during the normal synthesis process. Herein, 3D radial Co3O4 assembled with nanorods is fabricated by employing cobalt-based layered hydroxide metal salt (Co-LHMS) as a self-template. Meanwhile, Co3O4 with flake floral and dumbbell radial structure obtained by tuning the hydrothermal reaction time of precursors is used as a control group for gas sensing tests. The sensitivity of 3D radial Co3O4 to sub-ppm acetone is 4 times higher than other structures and the detection limit is 100 ppb at a relatively low working temperature of 200 degrees C, which is excellent among intrinsic acetone sensors based on pure Co3O4. The satisfactory gas sensing performance can be ascribed to the large specific surface, numerous trans-mission pathways, and low grain boundary resistance of the material. Furthermore, this work provides an idea for the further improvement of one-dimensional gas sensors.