Hierarchical spheres In2S3-based cataluminescence sensor for ammonium sulfide

In the present work, three different kinds of In2S3: hierarchical microspheres A, B and C (HMa, HMb and HMc), which were synthesized by a hydrothermal method in the sodium dodecyl sulfate-thiourea (SDS-thiourea) system. XRD, SEM and BET were used to characterize the prepared In2S3 materials. Compared with the other two kinds of In2S3, the as-prepared In2S3 hierarchical microspheres B (In2S3 HMb) exhibit the best cataluminescence response to ammonium sulfide. The response and recovery times of the home-made ammonium sulfide gas sensor with In2S3 hierarchical microspheres B as sensing materials were about 8 s and 24 s, respectively. The linear dependence of the sensitivity on the ammonium sulfide concentration was observed in the range of 4-200 ppm with an excellent selectivity. These results indicated that In2S3 hierarchical microspheres B would be a good candidate for fabricating practical cataluminescence ammonium sulfide sensor.