Waste honeycomb in-situ derived N-doped TiO2 with hierarchical porous nanostructure for rapid and selective H2 detection

Rapid-response and high-selectivity hydrogen gas (H2) detection is essential for safe utilization of hydrogen. Herein, we synthesize a N-doping TiO2-600 nanomaterial with hierarchical porous structure by using honeycomb bio-template, and develop it for high-performance H2 detection. The TiO2-600 sensing material is calcined at 600 degrees C, the formation of porous structure with large specific surface area (97.3 m2 g-1), which is capable to provide abundant adsorption sites for gas molecules. Moreover, the in-situ N-doping of TiO2-600 is beneficial for introducing more active sites, further promoting the redox reaction of H2 molecules. Benefited from these, TiO2- 600-based gas sensor not only exhibits a high response (Ra/Rg=796), rapid response and recovery speed (8 s and 3.8 s) at 250 degrees C for 1000 ppm H2, but also shows a good selectivity of H2 in various interference gases. Compared with traditional TiO2 nanoparticle-based gas sensor, the response value and speed of the TiO2-600-based H2 gas sensor are improved effectively, which is attributed to the synergistic effect of the changes in structure and chemical state of the bio-template in-situ derived TiO2. This work facilitates the bio-template application in highperformance gas sensing materials, and provides an avenue for the development of H2 sensors in the safe utilization of hydrogen energy.