journal article

Journal Article

Text

ACS Applied Nano Materials. 2022, 5(4), p. 4998-5005

Mechanochemical Synthesis of Dispersible Platinum Nanosheets for Enhanced Catalysis in a Microreactor

American Chemical Society

English

Text

2022-04-22

https://doi.org/10.1021/acsanm.1c04583

Koki Sasaki, Koji Miyake, Yoshiaki Uchida et al. Mechanochemical Synthesis of Dispersible Platinum Nanosheets for Enhanced Catalysis in a Microreactor. ACS Applied Nano Materials, 5 (4), 4998-5005, April 22, © 2022 American Chemical Society. https://doi.org/10.1021/acsanm.1c04583

Nanosheet fabrication usually requires some self-assembly process of the ingredients themselves or self-assembled templates to lead to the local anisotropy. Macroscopic forces and dynamics cannot usually generate the local anisotropy to synthesize nanosheets in a solution because the anisotropies of the macroscopic mechanical forces and dynamics are promptly relaxed in the molecular scale in a liquid phase. Here, we report the mechanochemical synthesis of dispersible platinum nanosheets (PtNSs) using a microreactor. This work is the first example of bottom-up nanosheet synthesis of a nonexfoliable compound in a microflow reactor. The nanosheets grow through the lateral fusion of nanoplatelets in the hydrophilic space of the stable hyperswollen lyotropic lamellar (HL) phase of a surfactant solution. The lateral fusion is accelerated as the flow rate increases because the area of the bilayer in the HL phase increases with shear stress. The mechanical energy to promote the growth of the PtNSs can also be extracted in different ways. Most simply, syringe pumps electrically generate it. We also illustrate mechanochemical synthesis using gravity, the most universal and eco-friendly energy source on the earth. It is also the first example of the fabrication of anisotropic nanoparticles using gravity. Larger PtNSs show higher catalytic activity for the reduction reaction from 4-nitrophenol to 4-aminophenol due to their dispersibility; surprisingly, the exponential increase of the fusion patterns of nanoplatelets dramatically reduces the agglomeration of PtNSs. These PtNSs perform better in catalysis and should be promising for hydrogen production, fuel cells, and sensors because of their large surface area and dispersibility. This method could open up a pathway to valuable nanosheets.

This document is the Accepted Manuscript version of a Published Work that appeared in final form in ACS Applied Nano Materials, © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://doi.org/10.1021/acsanm.1c04583

91505

Mechanochemical Synthesis of Dispersible Platinum Nanosheets for Enhanced Catalysis in a Microreactor

American Chemical Society

English

2022-04-22

ACS Applied Nano Materials

5

4

4998

5005

https://doi.org/10.1021/acsanm.1c04583

https://hdl.handle.net/11094/91505