Pd/Pt-Bimetallic-Nanoparticle-Doped In(2)O(3) Hollow Microspheres for Rapid and Sensitive H(2)S Sensing at Low Temperature

H(2)S is a poisonous gas that is widespread in nature and human activities. Its rapid and sensitive detection is essential to prevent it from damaging health. Herein, we report Pd- and Pt-bimetallic-nanoparticle-doped In(2)O(3) hollow microspheres that are synthesized using solvothermal and in situ reduction methods for H(2)S detection. The structure of as-synthesized 1 at% Pd/Pt-In(2)O(3) comprises porous hollow microspheres assembled from In(2)O(3) nanosheets with Pd and Pt bimetallic nanoparticles loaded on its surface. The response of 1 at% Pd/Pt-In(2)O(3) to 5 ppm H(2)S is 140 (70 times that of pure In(2)O(3)), and the response time is 3 s at a low temperature of 50 °C. In addition, it can detect trace H(2)S (as low as 50 ppb) and has superior selectivity and an excellent anti-interference ability. These outstanding gas-sensing performances of 1 at% Pd/Pt-In(2)O(3) are attributed to the chemical sensitization of Pt, the electronic sensitization of Pd, and the synergistic effect between them. This work supplements the research of In(2)O(3)-based H(2)S sensors and proves that Pd- and Pt-bimetallic-doped In(2)O(3) can be applied in the detection of H(2)S.