Molybdenum

Researchers develop unique 'Electronic tongue' using graphene and MoS2

Researchers at Penn State University recently developed an electronic “tongue” and an electronic “gustatory cortex” based on graphene ans MoS2. The artificial tastebuds comprise tiny, graphene-based electronic sensors called chemitransistors that can detect gas or chemical molecules. The other part of the circuit uses memtransistors, which is a transistor that remembers past signals, made with molybdenum disulfide. This allowed the researchers to design an “electronic gustatory cortex” that connect a physiology-drive “hunger neuron,” psychology-driven “appetite neuron” and a “feeding circuit.”   

For instance, when detecting salt, or sodium chloride, the device senses sodium ions, explained Subir Ghosh, a doctoral student in engineering science and mechanics and co-author of the study. “This means the device can ‘taste’ salt,” Ghosh said. 

Read the full story Posted: Oct 17,2023

Researchers pattern 2D materials using a commercial two-photon 3D printer

Researchers from the University of the Bundeswehr Munich & SENS Research Center and KTH Royal Institute of Technology recently demonstrated the noncontact and resist-free patterning of platinum diselenide (PtSe2), molybdenum disulfide (MoS2), and graphene layers with nanoscale precision at high processing speed while preserving the integrity of the surrounding material. 

The team used a commercial, off-the-shelf two-photon 3D printer to directly write patterns in the 2D materials with features down to 100 nm at a maximum writing speed of 50 mm/s. 

Read the full story Posted: Aug 02,2023

Researchers develop graphene/MoS2 micro-electrochemical capacitors for ultra-high charge storage

Researchers from the Indian Institute of Science have developed ultramicro-electrochemical capacitors with two-dimensional (2D) molybdenum disulphide (MoS2) and graphene-based electrodes. The development has great potential for wearables and implantable electronics as well as for sensors and miniature “smart” technology. 

The miniature energy storage device uses graphene Flakes and MoS2 alternately in each electrode - the cathode and anode. Gel was used as the electrolyte, which makes it possible to integrate micro-supercapacitors into chips. This would be difficult if not impossible with a water-soluble electrolyte. The capacitor showed a capacitance of 1.8 mF/cm2 for a single-layer structure (graphene-MoS2). The multilayer electrode structure, consisting of multiple alternating layers of graphene and molybdenum disulfide, gained 30 times greater capacitance, or 54 μF/cm2.

Read the full story Posted: Mar 16,2023

Researchers design impressive all-in-one miniature spectrometers using graphene and Mos2

An international team of researchers, including ones from Aalto University, Shanghai Jiao Tong University, Zhejiang University, Sichuan University,  Oregon State University, Yonsei University and the University of Cambridge, have designed a miniaturized spectrometer made of a ‘sandwich’ of different ingredients, including graphene, molybdenum disulfide, and tungsten diselenide. 

The spectrometer reportedly breaks all current resolution records, and does so in a much smaller package, thanks to computational programs and artificial intelligence. The new miniaturized devices could be used in a broad range of sectors, from checking the quality of food to analyzing starlight or detecting faint clues of life in outer space.

Read the full story Posted: Oct 22,2022

Researchers integrate large-area graphene-perovskite solar panels into stand-alone solar farm

An international research group, including teams from CHOSE at the University of Rome Tor Vergata, Hellenic Mediterranean University in Greece and others, has developed a large-area perovskite solar panel with graphene-doped electron transporting layers (ETLs) and functionalized molybdenum disulfide (fMoS2) buffer layers inserted between the perovskite layer and the hole transporting layer (HTL).

Nine GRAPE panels integrated in a stand-alone solar farm-powered infrastructure installed in Crete

The team reported that with increasing temperatures, the module exhibited a smaller drop in open-circuit voltage than commercially available crystalline silicon panels.

Read the full story Posted: Jun 24,2022

Researchers create miniscule graphene-MoS2 transistors

Researchers from China's Tsinghua University and East China Normal University have created a transistor with the smallest gate length ever reported. This milestone was made possible by using graphene and molybdenum disulfide and stacking them into a staircase-like structure with two steps.

Vertical MoS2 transistors with sub-1-nm gate lengths imageThe structure of the side-wall transistor: Silicon dioxide base (dark blue), aluminum covered in aluminum oxide (brown ), the thin, light blue strip is graphene, the yellow and black strip is molybdenum disulfide, and underneath it, the hafnium dioxide.

On the higher step, there is the source, and on top of the lower step, there is the drain. Both are made of a titanium palladium alloy separated by the surface of the stairs, which is made of a single sheet of a molybdenum disulfide (MoS2), itself resting on a layer of hafnium dioxide that acts as an electrical insulator.

Read the full story Posted: Mar 15,2022

Researchers experiment with LIG to create improved wearable health devices

A Penn State-led international research team (led by Professor Huanyu Larry Cheng at Penn State) recently published two studies that could boost research and development of future motion detection, tactile sensing and health monitoring devices.

Graphene made with lasers for wearable health devices image

There are various substances that can be converted into carbon to create graphene through laser radiation, in a process called laser-induced graphene (LIG). The resulting product can have specific properties determined by the original material. The team set out to test this process and has reached interesting conclusions.

Read the full story Posted: Sep 04,2021

Graphene ‘nano-origami’ could enable tiny microchips

Scientists at the University of Sussex have developed a technique for making tiny microchips from graphene and other 2D materials, using a form of ‘nano-origami’.

By creating distortions in the structure of the graphene, the researchers were able to make the nanomaterial behave like a transistor. We’re mechanically creating kinks in a layer of graphene, says Professor Alan Dalton of the School of Mathematical and Physics Sciences at the University of Sussex. It’s a bit like nano-origami. Using these nanomaterials will make our computer chips smaller and faster. It is absolutely critical that this happens as computer manufacturers are now at the limit of what they can do with traditional semiconducting technology. Ultimately, this will make our computers and phones thousands of times faster in the future.

Read the full story Posted: Feb 16,2021

New technique may enable large-area integration of 2D materials

Researchers affiliated with the Graphene Flagship from RWTH Aachen University, Universität der Bundeswehr München and AMO in Germany, KTH Royal Institute of Technology in Sweden and with Protemics have reported a new method to integrate graphene and 2D materials into semiconductor manufacturing lines, a milestone for the recently launched 2D-EPL project.

Schematic illustration of the methodology for wafer-level transfer of two-dimensional materials imageImage from Nature Communications

Two-dimensional (2D) materials have a huge potential for providing devices with much smaller size and extended functionalities with respect to what can be achieved with today's silicon technologies. But to exploit this potential, it is vital to be able to integrate 2D materials into semiconductor manufacturing lines - a notoriously difficult step. This new technique could be a step in the right direction as far as solving this problem is concerned.

Read the full story Posted: Feb 15,2021

Stretchable and ultrasensitive NO2 sensors based on rGO and MOS2 nanocomposites

Researchers at Penn State, Northeastern University and five universities in China have developed and tested a stretchable, wearable gas sensor for environmental sensing.

Stretchable, ultrasensitive, and low-temperature NO2 sensors based on MoS2@rGO nanocomposites image

The sensor combines a newly developed laser-induced graphene foam material with a unique form of molybdenum disulfide and reduced-graphene oxide nanocomposites. The researchers were interested in seeing how different morphologies of the gas-sensitive nanocomposites affect the sensitivity of the material to detecting nitrogen dioxide molecules at very low concentration. To change the morphology, they packed a container with very finely ground salt crystals.

Read the full story Posted: Sep 02,2020