Self-assembled synthesis of hierarchical Zn₂GeO₄ core–shell microspheres with enhanced photocatalytic activity

Abstract

Hierarchically spherical materials with a core-shell structure are of special interest for a variety of promising applications. Although some advanced synthetic methods have been reported, the development of a facile strategy to fabricate hierarchically spherical materials with a core-shell structure is still desirable. Herein, hierarchical Zn2GeO4 core-shell microspheres, with stacked nanoparticles at the core and well-aligned rods at the shell, are successfully synthesized through a triethylenetetramine (TETA)-induced self-assembly route. They exhibit relatively high photocatalytic activity and stability towards degradation of organic pollutants under UV light irradiation. In addition, other diverse hierarchical Zn2GeO4 macrocrystals can be successfully prepared by rationally tuning the reaction parameters. The present synthetic strategy may allow access to fabricating other multifunctional materials with special artistical morphologies.

Controllable Preparation and Electrochemical Behavior of Nanostructured Zn2GeO4

“…Then, 10 μL of the suspension was dropped onto the GCE and dried in air. The supporting electrolyte was the mixed solution of KNO 3 (0.1 mol L -1 ) and 5 mmol L -1 K 3 Fe(CN) 5 /K 3 Fe(CN) 6 (1:1).…”

“…Therein, one-dimensional nanostructured Zn 2 GeO 4 was especially concerned due to its excellent optical and photocatalytic properties. There were a large number of studies and reports [4,5,6]. However, from the present point of view, the research of Zn 2 GeO 4 is mainly focused on its application in photocatalysis.…”

Controlled synthesis of Bi2O3/BiOBr/Zn2GeO4 heterojunction photocatalysts with enhanced photocatalytic activity

“…Zn 2 GeO 4 , as a well‐known wide gap (4.68 eV) semiconductor, has been verified to be a promising photocatalyst for degradation of organic pollutants, hydrogen generation, reduction in carbon dioxide into hydrocarbon fuel, and purification of wastewater . The diffused s conduction bands in Zn 2 GeO 4 arising from Zn 4 s and Ge 4 s orbitals, are useful for the transformation of photogenerated electrons, enabling it a promising candidate as a photogenerated electron acceptor for the construction of photocatalytic heterojunctions.…”

Strongly Coupled Pt–Ni2GeO4 Hybrid Nanostructures as Potential Nanocatalysts for CO Oxidation

“…It is found that the hard template, polymethyl methacrylate (PMMA) nanopsheres, is essential to the formationo f the final products.T he as-prepared nanostructures can serve as an outstanding support for Pt nanoparticles after surface modification with l-lysine.I nt he catalytic test of CO oxidation, Pt-Ni 2 GeO 4 nanoflowers exhibited much higher catalytic performance compared with Pt-Ni 2 GeO 4 nanospheres, representing at ypical size-dependent catalytic property.As an ew type of mixed metal oxides, M x GeO y (M = Zn, Cu, Cd, Co and In) have shown great potentialities forc atalytic applications. [1][2][3][4][5][6][7][8][9][10] The co-existence of Ma nd Ge in as ingle compound could provide much more abundant physicala nd chemical properties, which is very attractive for chemists.F or example, Zn 2 GeO 4 ,r eporteda savisible-light-sensitive photocatalyst, has ab and gap of 2.6-2.8 eV and can achieve overall water splitting under visible light assisted by Pt and RuO 2 as co-catalysts. [11] Other kinds of M x GeO y ,i ncluding CuGeO 3 , [8] Cd 2 Ge 2 O 6 [9] and In 2 Ge 2 O 7[10] have also been reported very recently as different kinds of functional materials.H owever,t he synthesis of such mixed metal oxidesi ss till very challenging by wet chemistry routes because of the high valence state of Ge 4 + and high stability of GeO 2 that make GeO 3 2À only exist in alkaline environment.…”

“…As an ew type of mixed metal oxides, M x GeO y (M = Zn, Cu, Cd, Co and In) have shown great potentialities forc atalytic applications. [1][2][3][4][5][6][7][8][9][10] The co-existence of Ma nd Ge in as ingle compound could provide much more abundant physicala nd chemical properties, which is very attractive for chemists.F or example, Zn 2 GeO 4 ,r eporteda savisible-light-sensitive photocatalyst, has ab and gap of 2.6-2.8 eV and can achieve overall water splitting under visible light assisted by Pt and RuO 2 as co-catalysts. [11] Other kinds of M x GeO y ,i ncluding CuGeO 3 , [8] Cd 2 Ge 2 O 6 [9] and In 2 Ge 2 O 7…”