Coral-shaped tin oxide incorporated graphitic carbon nitride nanosheets as peroxidase mimic for sensitive colorimetric and fluorescence quenching based?detection of hydrogen peroxide

摘要

The enhanced peroxidase-like catalytic activity of coral-shaped graphitic carbon nitride (GCN) incorporated with tin oxide (SnO_(2)) is here reported and applied for the sensitive and selective colorimetric detection of hydrogen peroxide (H_(2)O_(2)). The SnO_(2)/GCN catalyzed the oxidation of 3, 3′, 5, 5′-tetramethylbenzidine, and H_(2)O_(2)which resulted in the appearance/change of color in the visible range. The results of peroxidase-like activity showed that the growth of SnO_(2)on GCN nanosheets improved structure, optical, and electronic properties considerably. SnO_(2)/GCN-40% showed the best activity because of the optimal loading of SnO_(2), unique structural, electronic, optical, and electrical properties. The catalytic reaction of coral-shaped SnO_(2)/GCN-40% followed the typical Michaelis–Menten equation, and the affinity of coral-shaped SnO_(2)/GCN-40% to TMB and H_(2)O_(2)was higher than that of horseradish peroxide. The present study showed a rapid, selective, and sensitive response toward the H_(2)O_(2)bioassay in a linear range of 10???655?μM with a limit of detection of 0.3?μM (S/N ratio of 3). The study may provide a promising method of performance improvement for applications in catalysis, biosensors, and nanomaterial-engineering fields. Graphical abstract Scheme shows the interaction of tin oxide with graphitic carbon nitride which resulted in a coral-shaped structure shown in SEM image. It also shows the interaction of tin oxide and graphitic carbon nitride with H_(2)O_(2)in the presence of TMB (3,3′, 5,5′-Tetramethylbenzidine) and as a consequence, TMB gets oxidized and ended up in change in color.