Portal de Periódicos da CAPES

A nanocomposite superstructure of metal oxides with effective charge transfer interfaces

2014; Nature Portfolio; Volume: 5; Issue: 1 Linguagem: Inglês

10.1038/ncomms4038

2041-1723

Zhenfeng Bian, Takashi Tachikawa, Peng Zhang, Mamoru Fujitsuka, Tetsuro Majima,

Gas Sensing Nanomaterials and Sensors

The alignment of nanoparticle building blocks into ordered superstructures is one of the key topics in modern colloid and material chemistry. Metal oxide mesocrystals are superstructures of assembled nanoparticles of metal oxides and have potentially tunable electronic, optical and magnetic properties, which would be useful for applications ranging from catalysis to optoelectronics. Here we report a facile and general approach for synthesizing metal oxide mesocrystals and developing them into new nanocomposite materials containing two different metals. The surface and internal structures of the mesocrystals were fully characterized by electron microscopy techniques. Single-particle confocal fluorescence spectroscopy, electron paramagnetic resonance spectroscopy and time-resolved diffuse reflectance spectroscopy measurements revealed that efficient charge transfer occurred between n-type and p-type semiconductor nanoparticles in the composite mesocrystals. This behaviour is desirable for their applications ranging from catalysis, optoelectronics and sensing, to energy storage and conversion. Mesocrystals are periodic arrangements of nanoparticles that allow for a tuning of the superstructure properties via its constituents. Here Bian et al. combine the properties of different nanocrystalline materials and fabricate a superstructure of two metal oxides with n- and p-type polarity.