Oxidative nucleation and growth of Janus-type MnOx-Ag and MnOx-AgI nanoparticles
Zhang, L (Zhang, Lei)[ 1,2 ] ; Jin, L (Jin, Lei)[ 2 ] ; Yang, Y (Yang, Yue)[ 2,3 ] ; Kerns, P (Kerns, Peter)[ 2 ] ; Su, XS (Su, Xingsong)[ 1,2 ] ; Meng, M (Meng, Michael)[ 2 ] ; Liu, B (Liu, Ben)[ 1 ]*（刘犇）; He, J (He, Jie)[ 2,4 ]*
[ 1 ] Nanjing Normal Univ, Sch Chem & Mat Sci, Jiangsu Collaborat Innovat Ctr Biomed Funct Mat, Jiangsu Key Lab New Power Batteries, Nanjing 210023, Jiangsu, Peoples R China
[ 2 ] Univ Connecticut, Dept Chem, Storrs, CT 06269 USA
[ 3 ] Nanjing Univ Sci & Technol, Dept Chem Engn, Nanjing 210094, Jiangsu, Peoples R China
[ 4 ] Univ Connecticut, Inst Mat Sci, Polymer Program, Storrs, CT 06269 USA
Janus nanoparticles (NPs) containing two chemically distinct materials in one system are of great significance for catalysis in terms of harnessing catalytic synergies that do not exist in either component. We herein present a novel synthetic method of two Janus-type MnOx-Ag and MnOx-AgI NPs. 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 partial iodization. Simultaneously, Mn2+ species in the primary MnO octahedra are oxidized during the growth of Ag NPs, leading to the formation of amorphous p-type MnOx domains. Therefore, the 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)(3)Cl-2 as an electron mediator. This intriguing synthesis may offer a new opportunity to develop asymmetric nanostructures of two semiconductors that will potentially be efficient photocatalysts for solar-driven water splitting.