0D/2D AuxPd100-x Nanocomposites with Enhanced Nanozyme Catalysis for Sensitive Glucose Detection

Here we report facile fabrication of two-dimensional (2D) Pd nanosheets-supported zero-dimensional (0D) Au nanoparticles via galvanic replacement. In the synthesis, the surface-clean Pd nanosheets premade were not only acted as a sacrifice template for replacing Pd atoms by Au3+ ions, but served as a support substrate to support Au nanoparticles. The morphology, structure and composition of products relied on the Au/Pd feed atomic ratio. Interestingly, the as-obtained 0D/2D AuxPd100-x (x = 4.5, 9.8 and 21) nanocomposites showed remarkably enhanced peroxidase-mimic catalysis in the model oxidation reaction, which followed the typical Michaelis-Menten theory. Compared to Pd NSs, the enhanced catalysis of AuxPd100-x was closely related to both the increased specific surface area and the modified electronic structure of Pd nanosheets, which resulted in a change in the catalytic pathway, i. e., from hydroxyl radical generation to rapid electron transfer. The work provides a simple yet efficient avenue to build...