Our research is directed towards creating nanostructured surfaces with novel functions at solid-liquid and liquid-liquid interfaces with the evaluation of their structural and functional properties from nanoscopic scale. Our current research projects are briefly described below;

<Electrochemical nano and micro fabrication processes>

We have developed nano and micro fabrication processes to create novel functional structures and surfaces though electrochemical approaches, and have applied them to develop various devices and systems such as micro thermoelectric devices, Zn based electrodes for large scale secondary batteries, array of ferromagnetic nanodots for ultra-high density data storage system, highly sensitive sensing devices for X ray imaging, and so on.

<Processes for producing solar grade silicon materials>

We have attempted to develop a new approach for producing high-purity Si materials for solar cell applications with the purity higher than 99.9999%, using wet-chemical and electrochemical processes. For this, we developed a new purification process of silica using wet chemical approaches with channel-flow type reactors, followed by contamination-free reduction process of silica to silicon using direct electrolysis using molten salt electrolyte. We have also developed a novel electrodeposition process for direct formation of Si thin films and nanopatterns, and investigated their formation mechanisms to achieve their optimization.

<Analysis of the solid/liquid interfacial reaction processes>

We have performed theoretical analysis of the electrochemical processes using ab initio MO(molecular orbital) and DFT(density functional theory) approaches, in combination with in situ analytical approaches with molecular-level resolution using SERS (surface enhanced Raman scattering) microscopy. For this, we developed novel devices, so called “plasmonic sensors” using the electrochemical micro fabrication processes, which can be widely applied for the analysis of various fields such as energy devices (batteries, solar cells), storage devices (hard disks, optical disks), mechanical devices (engines, bearings), and so on.

Ferromagnetic nanodot array

Micro reactor

Micro thermoelectric device