Ultrasensitive and selective hydrogen sensing of SnO 2 nanofibers decorated with Pd single atoms

DOI:  10.1016/j.snb.2024.136022

Keywords: Hydrogen sensor, Single atom, Pd catalysis, Limit of detection, fast-response, nanoparticles, sensor, microspheres, temperature, composite, Chemistry, Electrochemistry, Instruments & Instrumentation

Abstract: 

Highly accurate and sensitive hydrogen detection particularly at (sub)ppb level is crucial for large-scale use of green hydrogen energy. However, state-of-the-art hydrogen sensors usually have a ppm-level limit of detection (LOD). In this work, SnO 2 nanofibers were decorated with Pd single atoms using a scalable two-step annealing method, which remarkably boosted the H 2 sensing properties. The Pd-SnO 2 nanofiber sensor exhibited a response of 224 to 1000 ppm H 2 at the optimum operation temperature of 300 degrees C, which was 107 times higher than that of SnO 2 , achieving an LOD as low as 0.6 ppb. Moreover, a fast response time of 8.4 s, excellent selectivity, and humidity tolerance were observed. The superior H 2 sensing performance of Pd-SnO 2 nanofiber was ascribed to excellent catalysis of Pd single atoms and formation of heterojunction.