In situ growth of Pd nanosheets on MoS2 nanosheets as superior peroxidase mimetics for sensitive glucose detection

Regulating the interfacial structure of nanozyme to promote the charge transport efficiency is an excellent way to improve the catalytic activity. However, how to effectively enhance the interfacial charge transport efficiency of nanozyme is still a challenge. Herein, we used MoS₂ nanosheets (NSs) as template and support, which surface was decorated with Pd NSs through the in situ growth approach to form surface contact, realizing in strong interfacial interaction. Interestingly, the as-obtained 2D/2D MoS₂/Pd heterostructures showed enhanced peroxidase-mimic activity near 5 times compared to MoS₂ NSs. The enhanced catalysis of MoS₂/Pd was attributed to the change of catalytic pathway from hydroxyl radical generation to rapid electron transfer. Due to the excellent peroxidase activity of MoS₂/Pd, the colorimetric assay for glucose biosensing by combination with high specificity of glucose oxidase was further established, with a linear detection range of 5–2000 μM and a low limit of detection (LOD) of 0.8868 μM. The work provides a new strategy for the design of nanozymes with high catalytic performance for biocatalytic applications.