For instance, BSA-Au NCs [21], DNA-Au/Ag NCs [22],GSH-Ag NCs [23], DNA-Cu NCs [24] have been utilized directly for fabricating S2−sensors on the basis of fluorescence quenching. A new colorimetric strategy for detecting S2− has emerged recently based on gold nanoparticles (Au NPs) by taking advantage of their unique chemical, electrical, optical and catalytic properties [25–27]. A colorimetric assay for S2−has been developed based on color variation of GSH-Au NPs corresponding to the change from dispersed state to aggregated state [25]. The specific suifide-for-GSH ligand exchange reaction led to high selectivity but low sensitivity. The sensitivity was improved significantly by employing peroxidase like activity of bare Au NPs through amplification effect of the catalytic reaction [26]. Additionally, colorimetric sensing assays for S2−based on anti-aggregation or re-dispersion ofAuNPs are good alternatives to improve the sensitivity and selectivity [28]. These optical sensors have made great contributions in S2−sensing. Unfortunately, preparation of organic fluorescent probes or nanomaterials, and additional treatments such as separation, modification and purification, which are complicated and time-consuming, are essential for this process. Therefore, simple and efficient methods for S2−detection with high sensitivity and selectivity are still highly desired.