A Rapid Response Room Temperature Hydrogen Sensor Based on a Three-Dimensional Pd-In2O3/rGO Aerogel

A three-dimensional (3D) Pd-In2O3/rGO aerogel was fabricated via a one-step hydrothermal treatment and freeze-drying. The morphology and structure of the 3D Pd-In2O3/rGO aerogel were examined. The aerogel material had a porous network structure, which was particularly advantageous for gas adsorption. The Pd-In2O3 nanoparticles were uniformly grown on the thin layer of rGO. The specific surface area of the aerogel and its rich pore structure inhibited aggregation and accumulation of the nanoparticles. Moreover, this structure facilitated the formation of a P-N heterogeneous structure, which ultimately enabled successful detection of hydrogen (H-2) at room temperature. The sensitivity for 10 000 ppm H-2 at room temperature was 27.66, and detection was stable and reproducible. Most notably, the response and recovery times for H-2 were as short as 11 and 13 seconds, respectively. The addition of a hydrogen-sensitive functional material to a reduced graphene oxide aerogel shows great promise for room temperature gas sensing.