Tag Archives: Japan National Institute for Materials Science (NIMS)

Neuromorphic transistor with electric double layer

it may be my imagination but it seems as if neuromorphic (brainlike) engineering research has really taken off in the last few years and, even with my lazy approach to finding articles, I’m having trouble keeping up.

This latest work comes from Japan according to an August 4, 2023 news item on Nanowerk, Note: A link has been removed,

A research team consisting of NIMS [National Institute for Materials Science] and the Tokyo University of Science has developed the fastest electric double layer transistor using a highly ion conductive ceramic thin film and a diamond thin film. This transistor may be used to develop energy-efficient, high-speed edge AI devices with a wide range of applications, including future event prediction and pattern recognition/determination in images (including facial recognition), voices and odors.

The research was published in Materials Today Advances (“Ultrafast-switching of an all-solid-state electric double layer transistor with a porous yttria-stabilized zirconia proton conductor and the application to neuromorphic computing”).

A July 7, 2023 National Institute for Materials Science press release (also on EurekAlert but published August 3, 2023), which originated the news item, is arranged as a numbered list of points, the first point being the first paragraph in the news release/item,

2. An electric double layer transistor works as a switch using electrical resistance changes caused by the charge and discharge of an electric double layer formed at the interface between the electrolyte and semiconductor. Because this transistor is able to mimic the electrical response of human cerebral neurons (i.e., acting as a neuromorphic transistor), its use in AI devices is potentially promising. However, existing electric double layer transistors are slow in switching between on and off states. The typical transition time ranges from several hundreds of microseconds to 10 milliseconds. Development of faster electric double layer transistors is therefore desirable.

3. This research team developed an electric double layer transistor by depositing ceramic (yttria-stabilized porous zirconia thin film) and diamond thin films with a high degree of precision using a pulsed laser, forming an electric double layer at the ceramic/diamond interface. The zirconia thin film is able to adsorb large amounts of water into its nanopores and allow hydrogen ions from the water to readily migrate through it, enabling the electric double layer to be rapidly charged and discharged. This electric double layer effect enables the transistor to operate very quickly. The team actually measured the speed at which the transistor operates by applying pulsed voltage to it and found that it operates 8.5 times faster than existing electric double layer transistors, setting a new world record. The team also confirmed the ability of this transistor to convert input waveforms into many different output waveforms with precision—a prerequisite for transistors to be compatible with neuromorphic AI devices.

4. This research project produced a new ceramic thin film technology capable of rapidly charging and discharging an electric double layer several nanometers in thickness. This is a major achievement in efforts to create practical, high-speed, energy-efficient AI-assisted devices. These devices, in combination with various sensors (e.g., smart watches, surveillance cameras and audio sensors), are expected to offer useful tools in various industries, including medicine, disaster prevention, manufacturing and security.

Here’s a link to and a citation for the paper,

Ultrafast-switching of an all-solid-state electric double layer transistor with a porous yttria-stabilized zirconia proton conductor and the application to neuromorphic computing by Makoto Takayanagi, Daiki Nishioka, Takashi Tsuchiya, Masataka Imura, Yasuo Koide, Tohru Higuchi, and Kazuya Terabe. Materials Today Advances [June 16, 2023]; DOI : 10.1016/j.mtadv.2023.10039

This paper is open access.

May 28, 2018 release date for inorganic material database ‘AtomWork-Adv’

Announced in a May 23, 2018 news item on Nanowerk,

[Japan National Institute for Materials Science] NIMS will make its inorganic materials database, AtomWork-Adv (pronounced “atom work advanced”), available to the general public as a fee-based service starting Monday, May 28, 2018. This service will be provided by the Data Platform from the Center for Materials Research by Information Integration (CMI2), Research and Services Division of the Materials Data and Integrated System (MaDIS), NIMS.

A May 23, 2018 NIMS press release, which originated the news item, fills out the details (Note: Paragraph 1 is largely repetitive but there is contact information in there),

  1. NIMS will make its inorganic materials database, “AtomWork-Adv” (pronounced “atom work advanced”), available to the general public as a fee-based service starting Monday, May 28, 2018. This service will be provided by the Data Platform (Yibin Xu, Director) from the Center for Materials Research by Information Integration (CMI2), Research and Services Division of the Materials Data and Integrated System (MaDIS), NIMS. AtomWork-Adv markedly improves upon the amount of data available and the usability of the current web-based “AtomWork” database. We hope that this service will promote data-driven materials development using AI and machine learning.
  2. The increasingly popular use of AI and machine learning in materials development requires a high-quality materials database. NIMS publicized the AtomWork inorganic materials database—constructed using literature published up to 2002—on its MatNavi webpage (http://mits.nims.go.jp/index.html). While AtomWork is available free of charge, the data it contains is not updated and its functions, such as allowing users to copy, download and search data, are limited.
  3. The AtomWork-Adv database compiles crystal structure data (approx. 274,000 datasets), X-ray diffraction data (approx. 496,000 datasets), material properties data (approx. 298,000 datasets) and phase diagram data (approx. 40,000 datasets) collected from literature published up to 2014. The number of datasets in these categories are about three to five times greater than those in the Atom Work database. In addition, AtomWork-Adv is equipped with user-friendly functions, such as a versatile search tool which enables searches by element, composition, crystal structure and material property, a matrix function which identifies the number of datasets available for a specific binary material combination and an automatic charting function which allows the plotting of a graph between two material property variables and which displays material names in relation to these variables. Users can download data for use in data science-driven materials research and development (the number of downloads is restricted).
  4. Data will be continuously added to and updated in the fee-based AtomWork-Adv database. We are planning to add new data collected from literature between 2015 and 2016 to the database during FY2018.
  5. This database project was supported by the “Materials Research by Information Integration” Initiative (MI2I) sponsored by the Japan Science and Technology Agency (JST)’s Support Program for Starting up Innovation Hub.

Happy atom hunting!

Peripheral nerves (a rat’s) regenerated when wrapped with nanomesh fiber

A Feb.28,2017 news item on Nanowerk announces a proposed nerve regeneration technique (Note: A link has been removed),

A research team consisting of Mitsuhiro Ebara, MANA associate principal investigator, Mechanobiology Group, NIMS, and Hiroyuki Tanaka, assistant professor, Orthopaedic Surgery, Osaka University Graduate School of Medicine, developed a mesh which can be wrapped around injured peripheral nerves to facilitate their regeneration and restore their functions (Acta Biomaterialia, “Electrospun nanofiber sheets incorporating methylcobalamin promote nerve regeneration and functional recovery in a rat sciatic nerve crush injury model”).

This mesh incorporates vitamin B12—a substance vital to the normal functioning of nervous systems—which is very soft and degrades in the body. When the mesh was applied to injured sciatic nerves in rats, it promoted nerve regeneration and recovery of their motor and sensory functions.

A Feb. 27, 2017 Japan National Institute for Materials Science (NIMS) press release for Osaka University, which originated the news item, provides more detail,

Artificial nerve conduits have been developed in the past to treat peripheral nerve injuries, but they merely form a cross-link to the injury site and do not promote faster nerve regeneration. Moreover, their application is limited to relatively few patients suffering from a complete loss of nerve continuity. Vitamin B12 has been known to facilitate nerve regeneration, but oral administration of it has not proven to be very effective, and no devices capable of delivering vitamin B12 directly to affected sites had been available. Therefore, it had been hoped to develop such medical devices to actively promote nerve regeneration in the many patients who suffer from nerve injuries but have not lost nerve continuity.

The NIMS-Osaka University joint research team recently developed a special mesh that can be wrapped around an injured nerve which releases vitamin B12 (methylcobalamin) until the injury heals. By developing very fine mesh fibers (several hundred nanometers in diameter) and reducing the crystallinity of the fibers, the team successfully created a very soft mesh that can be wrapped around a nerve. This mesh is made of a biodegradable plastic which, when implanted in animals, is eventually eliminated from the body. In fact, experiments demonstrated that application of the mesh directly to injured sciatic nerves in rats resulted in regeneration of axons and recovery of motor and sensory functions within six weeks.

The team is currently negotiating with a pharmaceutical company and other organizations to jointly study clinical application of the mesh as a medical device to treat peripheral nerve disorders, such as CTS.

This study was supported by the JSPS KAKENHI program (Grant Number JP15K10405) and AMED’s Project for Japan Translational and Clinical Research Core Centers (also known as Translational Research Network Program).

Figure 1. Conceptual diagram showing a nanofiber mesh incorporating vitamin B12 and its application to treat a peripheral nerve injury.

Here’s a link to and a citation for the paper,

Electrospun nanofiber sheets incorporating methylcobalamin promote nerve regeneration and functional recovery in a rat sciatic nerve crush injury model by Koji Suzuki, Hiroyuki Tanaka, Mitsuhiro Ebara, Koichiro Uto, Hozo Matsuoka, Shunsuke Nishimoto, Kiyoshi Okada, Tsuyoshi Murase, Hideki Yoshikawa. Acta Biomaterialia http://dx.doi.org/10.1016/j.actbio.2017.02.004 Available online 5 February 2017

This paper is behind a paywall.

Characterizing anatase titanium dixoide at the nanoscale

An international collaboration of researchers combined atomic force microscopy (AFM) and scanning tunneling microscopy (STM) to characterize anatase titanium dixoxide. From a Sept. 14, 2015 news item on Azonano,

A [Japan National Institute for Materials Science] NIMS research team successfully identified the atoms and common defects existing at the most stable surface of the anatase form of titanium dioxide by characterizing this material at the atomic scale with scanning probe microscopy. This work was published under open access policy in the online version of Nature Communications on June 29, 2015.

A June 29, 2015 NIMS press release, which originated the news item, includes the paper’s abstract in numbered point form,

  1. The research team consisting of Oscar Custance and Tomoko Shimizu, group leader and senior scientist, respectively, at the Atomic Force Probe Group, NIMS, Daisuke Fujita and Keisuke Sagisaka, group leader and senior researcher, respectively, at the Surface Characterization Group, NIMS, and scientists at Charles University in the Czech Republic, Autonomous University of Madrid in Spain, and other organizations combined simultaneous atomic force microscopy (AFM) and scanning tunneling microscopy (STM) measurements with first-principles calculations for the unambiguous identification of the atomic species at the most stable surface of the anatase form of titanium dioxide (hereinafter referred to as anatase) and its most common defects.
  2. In recent years, anatase has attracted considerable attention, because it has become a pivotal material in devices for photo-catalysis and for the conversion of solar energy to electricity. It is extremely challenging to grow large single crystals of anatase, and most of the applications of this material are in the form of nano crystals. To enhance the catalytic reactivity of anatase and the efficiency of devices for solar energy conversion based on anatase, it is critical to gain in-depth understanding and control of the reactions taking place at the surface of this material down to the atomic level. Only a few research groups worldwide possess the technology to create proper test samples and to make in-situ atomic-level observations of anatase surfaces.
  3. In this study, the research team used samples obtained from anatase natural single crystals extracted from naturally occurring anatase rocks. The team characterized the (101) surface of anatase at atomic level by means of simultaneous AFM and STM. Using single water molecules as atomic markers, the team successfully identified the atomic species of this surface; result that was additionally confirmed by the comparison of simultaneous AFM and STM measurements with the outcomes of first-principles calculations.
  4. In regular STM, in which an atomically sharp probe is scanned over the surface by keeping constant an electrical current flowing between them, it is difficult to stably image anatase surfaces as this material presents poor electrical conductivity over some of the atomic positions of the surface. However, simultaneous operation of AFM and STM allowed imaging the surface with atomic resolution even within the materials band gap (a region where the flow of current between the probe and the surface is, in principle, prohibited). Here, the detection of inter-atomic forces between the last atom of the atomically sharp probe and the atoms of the surface by AFM was of crucial importance. By regulating the probe-surface distance using AFM, it was possible to image the surface at atomic-scale while collecting STM data over both conductive and not conductive areas of the surface. By comparing simultaneous AFM and STM measurements with theoretical simulations, the team was not only able to discern which atomic species were contributing to the AFM and the STM images but also to identify the most common defects found at the surface.
  5. In the future, based on the information gained from this study, the NIMS research team will conduct research on molecules of technologically relevance that adsorb on anatase and characterize these hybrid systems by using simultaneous AFM and STM. Their ultimate goal is to formulate novel approaches for the development of photo-catalysts and solar cell materials and devices.

Here’s a link to and a citation for the paper,

Atomic species identification at the (101) anatase surface by simultaneous scanning tunnelling and atomic force microscopy by Oleksandr Stetsovych, Milica Todorović, Tomoko K. Shimizu, César Moreno, James William Ryan, Carmen Pérez León, Keisuke Sagisaka, Emilio Palomares, Vladimír Matolín, Daisuke Fujita, Ruben Perez, & Oscar Custance. Nature Communications 6, Article number: 7265 doi:10.1038/ncomms8265 Published 29 June 2015

This is an open access paper.

Speeding up the process for converting carbon dioxide into hydrocarbon fuel

This is a personal thrill; it’s the first time in seven years that I’ve received a press release directly from an institution in Asia.

A March 10, 2015 MANA, the International Center for Materials Nanoarchitectonics at NIMS (National Institute for Materials Science) press release announces and describes hydrocarbon fuel research from Japan and China first published online in Nov. 2014 and later in print in January 2015,

A combination of semiconductor catalysts, optimum catalyst shape, gold-copper co-catalyst alloy nanoparticles and hydrous hydrazine reducing agent enables an increase of hydrocarbon generation from CO2 by a factor of ten.

“Solar-energy-driven conversion of CO2 into hydrocarbon fuels can simultaneously generate chemical fuels to meet energy demand and mitigate rising CO2 levels,” explain Jinhua Ye and her colleagues at the International Center for Materials Nanoarchitectonics in their latest report. Now the research team have identified the conditions and catalysts that will maximise the yield of hydrocarbons from CO2, generating ten times previously reported production rates.

Carbon dioxide can be converted into a hydrocarbon by means of ‘reduction reactions’ -a type of reaction that involves reducing the oxygen content of a molecule, increasing the hydrogen content or increasing the electrons. In photocatalytic reduction of CO2 light activates the catalyst for the reaction.

Ye and his team introduced four approaches that each contributed to an increased reaction rate. First, they combined two known semiconductor photocatalysts strontium titanate (STO) and titania [titanium dioxide] (TiO2) – which led to the separation of the charges generated by light and hence a more effective photocatalyst. Second, the high surface area of the nanotubes was made greater by holes in the tube surfaces, which enhances catalysis by increasing the contact between the gases and catalysts. Third, the tubes were decorated with gold-copper (Au3Cu) nanoparticle co-catalysts to further enhance the catalysis, and fourth, they used hydrous hydrazine (N2H4•H2O) as the source of hydrogen.

Although the high hydrogen content of hydrous hydrazine is widely recognised in the context of hydrogen storage there are no previous reports of its use for reduction reactions. The researchers demonstrated that the reducing properties of hydrous hydrazine were so great that oxidation of the co-catalytic nanoparticles – a problem when water or hydrogen are used – was avoided.

The researchers conclude their report, “This opens a feasible route to enhance the photocatalytic efficiency, which also aids the development of photocatalysts and co-catalysts.”

Affiliations

The researchers on this project are associated with the following institutions:

International Center for Materials Nanoarchitectonics (MANA), and the Environmental Remediation Materials Unit,  National Institute for Materials Science (NIMS) 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan

Graduate School of Chemical Science and Engineering, Hokkaido University, Sapporo 060-0814, Japan

TU-NIMS Joint Research Center, School of Material Science and Engineering, Tianjin University 92 Weijin Road, Tianjin,  P.R. China

Here’s a link to and a citation for the paper,

Photocatalytic Reduction of Carbon Dioxide by Hydrous Hydrazine over Au–Cu Alloy Nanoparticles Supported on SrTiO3/TiO2 Coaxial Nanotube Arrays by Dr. Qing Kang, Dr. Tao Wang, Dr. Peng Li, Dr. Lequan Liu, Dr. Kun Chang, Mu Li, and Prof. Jinhua Ye. Angewandte Chemie International Edition Volume 54, Issue 3, pages 841–845, January 12, 2015 DOI: 10.1002/anie.201409183 Article first published online: 24 NOV 2014

© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

This research is behind a paywall.