日本語

 

Department of Energy and Environment

Promoting green innovation

To promote green innovation, AIST is developing technologies for increased use of alternative energy technologies, such as renewable energy sources that reduce greenhouse gas emissions (energy creation), high-density storage of energy (energy storage), highly efficient conversion and use of energy (energy saving), effective utilization of energy resources, and evaluation and reduction of environmental risks.

Figure

New Research Results

World’s First Demonstration of a Hybrid Transistor Integrating GaN and SiC

A hybrid transistor with monolithically integrated a gallium nitride (GaN)-based high electron mobility transistor and a silicon carbide (SiC)-based PN diode, was successfully fabricated and demonstrated by AIST researchers for the first time in the world. The prototype hybrid transistor achieves both the GaN feature of low on-resistance and the proven non-destructive breakdown of SiC diodes. As a result, application of hybrid transistors is expected to power converters for applications that require high reliability, such as electric vehicles and photovoltaic power generation. Going forward, further optimization of the device fabrication process will be promoted to establish a path to practical application.

Figure of new research results Energy and Environment

Hybrid transistors on a 100-mm diameter wafer and equivalent circuit

Clarifying Conditions for Enhancing the Conversion Efficiency of Powdered Photocatalysts that Generate Hydrogen from Water Under Visible Light

In collaboration with research partners*, AIST researchers clarified the conditions needed for an oxysulfide photocatalyst Y2Ti2O5S2, which splits water into hydrogen and oxygen under visible light, to achieve a conversion efficiency from solar energy to reaction energy (hereafter, “conversion efficiency”) over 10 % for practical use.
In this research, by using transient absorption spectroscopy, the photo-excited carrier concentration of Y2Ti2O5S2 was recorded with time over the range of six orders of magnitude from 1 picosecond to 1 microsecond, and physical properties such as the lifetime of photo-excited carrier (hereafter, “carrier lifetime”) in powder form were obtained by analyzing the recorded data. Then, simulations were performed using he physical properties to obtain the relationship between the conversion efficiency and the powder particle size. It was found that the conversion efficiency could exceed 10 % by reducing the particle size below 1 micrometer. Furthermore, simulation analysis assuming the doping effect to extend the carrier lifetime suggested the conversion efficiency larger than 10 % by reducing the electron concentration to 1/100th of the current level.
The results of this research provide a quantitative guideline for further enhancing the conversion efficiency of the oxysulfide photocatalysts and development of new materials that more efficiently generate hydrogen from water.
*The Research Association of Artificial Photosynthetic Chemical Process (ARPChem) commissioned by NEDO, Tokushima University, Kyoto University, and Shinshu University.

Figure of new research results Energy and Environment

(Left) Time evolution of the photo-excited carrier concentration of the oxysulfide photocatalyst Y2Ti2O5S2 with respect to that at 1 picosecond after light irradiation. The photograph shows the powdered Y2Ti2O5S2 used for this measurement. (Right) Performance prediction with the size of a photocatalyst particle.

Research Unit

Open Innovation Laboratory

Since FY 2016, as a part of the “Open Innovation Arena concept” promoted by the Ministry of Economy, Trade and Industry (METI), AIST has created the concept of “open innovation laboratories” (OILs), collaborative research bases located on university campuses, and has been engaged in their provision. We are planning to establish more than ten OILs by FY 2020.

AIST will merge the basic research carried out at universities, etc. with AISTʼs goal-oriented basic research and applied technology development, and will promote bridging research and evelopment and industry by the establishment of OILs.

  • AIST-Kyoto University Chemical Energy Materials Open Innovation Laboratory (ChEM-OIL) (terminated at the end of March 2022)

Cooperative Research Laboratories

In order to conduct research and development more closely related to strategies of companies, we have established collaborative research laboratories, bearing partner company names.

Partner companies provide their researchers and funding, and AIST provides research resources, such as its researchers, research facilities, and intellectual property. The loaned researchers of companies and AIST researchers jointly conduct research and development.

By setting up cooperative research laboratories, we will accelerate the commercialization of our goal-oriented basic research and application research with partner companies.

  • Shimizu-AIST Zero Emission Hydrogen town Cooperative Research Laboratory
  • Hitachi Zosen - AIST Collaborative Research Laboratory for Sustainable Green Energy Production

▲ ページトップへ