LAUSR

Nanocatalysts depended colorimetric assay possesses the advantage of fast detection and provides a novel avenue for the detection of hydrogen sulfide (H2S). The exploration of nanocatalysts with superior catalytic activity is challenging to achieve ultrasensitive colorimetric assay of H2S. Herein, 1.7 ± 0.2 nm ruthenium nanoparticles (Ru NPs) were prepared and exhibited outstanding catalytic hydrogenation activity. The degradation rate constants of orange I in the presence of Ru NPs were 4-, 47- and 165-fold higher than those of platinum (Pt) NPs, iridium (Ir) NPs and control groups without catalysts. H2S-induced deactivation of Ru NP catalysts was designed for the sensitive colorimetric assay of H2S, attributing to the poor thiotolerance of Ru NPs. A standard linear curve between the rate constants and the concentration of H2S was established. The limit of detection (LOD) was as low as 0.6 nM. A Ru NPs based colorimetric principle was also used to fabricate colorimetric paper strips for the on-site visua...