Structural Evolution of Ag/BN Hybrids via Polyol-Assisted Fabrication Process and Their Catalytic Activity in CO Oxidation
Herein we analyzed the chemical reactions occurring in the process of Ag/BN hybrid fabrication in polyethylene glycol (PEG) using h-BN nano- and microparticles (BNNPs and BNMPs) during AgNO3 decomposition under UV irradiation. Decomposition of AgNO3 causes formation of Ag nanoparticles (AgNPs) and PEG oxidation reaction, the products of which interact with Ag to form Ag acetate. Polymer matrix surrounding AgNPs prevents their growth during fabrication process. Additional low temperature annealing leads to the decomposition of Ag acetate phase hereby increasing the volume fraction of AgNPs. In case of the BNNPs, the AgNP size is smaller and their distribution is more homogeneous. BNNPs surface oxidation was shown to be an important factor leading to enhanced catalytic activity of Ag/BN hybrids in the CO oxidation reaction: Tinitiation=150°C and T100=200°C. Theoretical modelling suggests that the high catalytic activity of Ag/BN nanohybrids can be explained by formation of thin B-O-Ag layers.