Assistant professor：Takashi Harumoto
●Ishiguro laboratory advocates ‘nano-system materials engineering’. Keywords are ‘nano’, ‘water’, ‘light’ and ‘bio’.
●The substance and material, which surround us have characteristic nanostructure. This is essential to express their function. AT first, our laboratory observes its nanostructure itself with our eyes. This is “Seeing is believing” We will create new equipment which is required to observe the unknown and unseen material by ourselves. Furthermore, we create brand-new function by self-structured by the material.
●We are strongly interested in ‘water’, which is common material. Why? Many chemical reactions happen in water solution. This is the reaction in our fresh living cell. Moreover, we have already succeeded in making the perfectly transparent glasses reacted by opaque aluminum thin film and ultrapure ‘water’. This is the invention of applying to the efficiency of solar battery.
●In order to observe these reaction on the spot, we have made an infrared equipment. Owing to this one, we have succeeded in observing the more vivid water molecule vibration. We are also trying to observe the vibration of ATP (adenosine triphosphate) which is the origin of life energy metabolism.
●Metal becomes hydroxide after reacting water. Furthermore, it changes into oxide after getting rid of water. Amino acid molecule becomes combined protein by dehydration. ……. Looking at these processes, you can understand reaction taking water in and out is basic principle of biological soft matter and hydrothermal reaction.
●We observe the materials from this point of views. This is also the theme of our research. Efficient use of solar light energy, comprehension of life-substance, biomimetics, brittle fracture due to the presence of the water, developing a device to find circulating tumor cell in the blood, detection of bio-molecules constituting RNA etc. You may wonder if these are not related with each other. In these our research subjects we think we can find a commonality. This may because we are living on Earth of water planet.
Perfectly transparent glass
Use of renewable solar energy is a long-cherished desire of our mankind. A number of techniques are integrated to achieve high efficiency of solar cell. Light energy of about more than 15% is lost by reflections at surface and interface because of its multilayered structure. This loss can be reduced by forming nano-scaled surface roughness, which plays a role of the graded refractive structure. The photograph shows an example of perfectly transparent glasses (100% transmittance). This is formed by reforming of opaque metallic aluminum thin film in the ultrapure water.
Basic study of the water
Water covers about 70% of the surface of the earth. 60% of our body is composed of water. Water is absolutely necessary to preserve our life. However there are still lots of unknown things about the water. Actually, we cannot see molecules themselves. Instead of it, we can hear a kind of sound of molecular oscillation and rotation. One of the methods is infrared spectroscopy. We have succeeded for the first time in observing transmission absorption spectrum of the water at high pressure and high temperature. Furthermore, we observed the super critical state of the water. Water, which is believed to be transparent, becomes dark because of its strong fluctuation, as shown in the photograph. This is also the fruit of our laboratory.
In-situ observation of biological soft matter
Our body is composed of various materials. DNA, cell, blood, protein, etc., these are called ‘biological matter’. Reaction and/ or mechanism is deeply related to their form or structure. We are trying to observe the structure by using transmission electron microscope. Photograph shows a high resolution image of antibody.