Environment and Energy

New Energy

Okada Laboratory

Material
Environment and Energy
Information

Multiband Engineering in Thin Films
for Intermediate Band Solar Cell

Chemical Biomedicine

At Okada Laboratory, we conduct research on high-efficiency solar cells
incorporating new semiconductor materials and quantum nanostructures in aim
for doubling the efficiency of present solar cells. Quantum dots are semiconductormaterials processed at the nanometer scale. They can confine the electrons
within the dot and so often referred to as "artificial atoms." They can be used toenhance the output current and hence the efficiency by absorbing infrared light,
which the conventional solar cells cannot harvest to generate power.

Professor

Yoshitaka OKADA
Research Area
Next-generation solar cells, Semiconductor crystal growth,
Epitaxial lift-off thin-film solar cells

Project Research Associate

Yusuke OTEKI
Research Area

Barrier Free

Next-generation solar cells, Semiconductor crystal growth,
Epitaxial lift-off thin-film solar cells

ColumnThin film solar cells and substrate reuseSocial Science
Laboratory forInterdiciplinary Activities

In addition, we are developing technologies aimed at reducing the production costof high-efficiency solar cells. Since the substrate cost constitutes the highest
proportion of the overall cost, we are advancing the epitaxial lift-off technology,
which involves removing and reusing substrates from solar cells layers. The
resulting thin-film solar cells, being flexible and lightweight after substrate
removal, are suitable for applications such as space and automotive solar cells,
aiming to expand the adoption of solar power generation. We also work on thewafer-scale synthesis of ultra-thin two-dimensional layered materials for solar celland photodetector applications.

When thinking about global environmental
issues,we often hear the phrase 'Think
Globally, Act Locally.' It implies 'consider theglobal impact and take action in ways that you
can as an individual.'

However, forresearchers, the important approach might be'Think Locally, Act Globally.' In your daily life,
put in your best effort and work hard in yourgiven environment (your laboratory)(ThinkLocally). Then, present your research findings
to the world, join discussions throughCooperative Laboratories

networks with research colleagues around theglobe. Ideas and thoughts generated fromthese discussions will be fed back into yourown research, allowing it to develop to thenext level. Just as athletes are inspired bySocial Cooperation
Research Departments

their rivals and strive to improve their own
skills, researchers are both colleagues andcompetitors at the same time. To students andyoung researchers, I encourage you todevelop the skills necessary to perform on aCorporate SponsoredResearch Programs

global stage (Act Globally). This is not only
essential for the advancement of science and
1 Schematic of a quantum dot solar cell

2 Thin-film solar cells by developed with
ELO technique

technology, but it also determines the strengthof humanity as we tackle future global
environmental and energy issues.

Research Organization

http://mbe.rcast.u-tokyo.ac.jp
okada@mbe.rcast.u-tokyo.ac.jp

3 Molecular beam epitaxy (MBE) is used tofabricate the solar cells

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