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Title: Oxidative nucleation and growth of Janus-type MnOx-Ag and MnOx-AgI nanoparticles
Janus nanoparticles (NPs) containing two chemically distinct materials in one system are of great significance for catalysis in terms of harnessing catalytic synergies that are not exist in either component. We herein present a novel synthetic method of two Janus-type MnOx-Ag and MnOx-AgI NPs for efficient photochemical water oxidation. The synthesis of Janus-type MnOx-AgI NPs is based on the oxidative nucleation and growth of Ag domains on MnO first and the subsequent iodization of Ag. A mild and non-disruptive iodization strategy is developed to yield Janus MnOx-AgI NPs, in which converting Ag to AgI domains with iodomethane (CH3I) is achieved through the partial iodization. Simultaneously, Mn2+ species in the primary MnO octahedrons are oxidized during the growth of Ag NPs, leading to the formation of amorphous p-type MnOx domains. Therefore, as-resultant Janus-type MnOx-AgI NPs combining two semiconductors into an integrated nanostructure can be used as an efficient photocatalyst for visible light-driven water oxidation. Janus MnOx-AgI NPs show an expected photocatalytic activity even in the absence of Ru(bpy)3Cl2 as an electron mediator. This intriguing synthesis may open up a new opportunity to develop asymmetric nanostructures of two semiconductors that will potentially be efficient photocatalysts for solar-driven water splitting.  more » « less
Award ID(s):
1705566
PAR ID:
10104131
Author(s) / Creator(s):
; ; ; ; ; ; ;
Date Published:
Journal Name:
Nanoscale
ISSN:
2040-3364
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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