Graphene And Fractals Boost The Solar Power Storage By 3000%

Inspired by an American fern, researchers have developed a groundbreaking prototype that could be the answer to the storage challenge still holding solar back as a total energy solution. The new type of electrode created by RMIT University (Australia) researchers could boost the capacity of existing integrable storage technologies by 3000 per cent. But the graphene-based prototype also opens a new path to the development of flexible thin film all-in-one solar capture and storage, bringing us one step closer to self-powering smart phones, laptops, cars and buildings. The new electrode is designed to work with supercapacitors, which can charge and discharge power much faster than conventional batteries. Supercapacitors have been combined with solar, but their wider use as a storage solution is restricted because of their limited capacity.

RMIT’s Professor Min Gu said the new design drew on nature’s own genius solution to the challenge of filling a space in the most efficient way possible – through intricate self-repeating patterns known as “fractals”.

The leaves of the western swordfern are densely crammed with veins, making them extremely efficient for storing energy and transporting water around the plant,” said Gu, Leader of the Laboratory of Artificial Intelligence Nanophotonics at RMIT.

mimicking fern

Our electrode is based on these fractal shapes – which are self-replicating, like the mini structures within snowflakes – and we’ve used this naturally-efficient design to improve solar energy storage at a nano level. “The immediate application is combining this electrode with supercapacitors, as our experiments have shown our prototype can radically increase their storage capacity30 times more than current capacity limits.   “Capacity-boosted supercapacitors would offer both long-term reliability and quick-burst energy release – for when someone wants to use solar energy on a cloudy day for example – making them ideal alternatives for solar power storage.”  Combined with supercapacitors, the fractal-enabled laser-reduced graphene electrodes can hold the stored charge for longer, with minimal leakage.

Source: https://www.rmit.edu.au/

Nano Printing Heralds NanoComputers Era

A new technique using liquid metals to create integrated circuits that are just atoms thick could lead to the next big advance for electronics. The process opens the way for the production of large wafers around 1.5 nanometres in depth (a sheet of paper, by comparison, is 100,000nm thick). Other techniques have proven unreliable in terms of quality, difficult to scale up and function only at very high temperatures – 550 degrees or more.

Professor Kourosh Kalantar-zadeh, from RMIT’s School of Engineering in Australia , led the project with  colleagues from RMIT and researchers from CSIRO, Monash University, North Carolina State University and the the University of California, He observed that the electronics industry had “hit a barrier.

nano printing

The fundamental technology of car engines has not progressed since 1920 and now the same is happening to electronics. Mobile phones and computers are no more powerful than five years ago. That is why this new 2D printing technique is so important – creating many layers of incredibly thin electronic chips on the same surface dramatically increases processing power and reduces costsIt will allow for the next revolution in electronics.

Benjamin Carey, a researcher with RMIT and the CSIRO, said creating electronic wafers just atoms thick could overcome the limitations of current chip production. It could also produce materials that were extremely bendable, paving the way for flexible electronics. “However, none of the current technologies are able to create homogenous surfaces of atomically thin semiconductors on large surface areas that are useful for the industrial scale fabrication of chips.  Our solution is to use the metals gallium and indium, which have a low melting point.  These metals produce an atomically thin layer of oxide on their surface that naturally protects them. It is this thin oxide which we use in our fabrication method,”  explains Carey.

By rolling the liquid metal, the oxide layer can be transferred on to an electronic wafer, which is then sulphurised. The surface of the wafer can be pre-treated to form individual transistors.  We have used this novel method to create transistors and photo-detectors of very high gain and very high fabrication reliability in large scale,” he adds.

The paper outlining the new technique has been published in the journal Nature Communications.

Source: http://www.rmit.edu.au/

How To Fabricate The Hardest Diamond

The Australian National University (ANU) has led an international project to make a diamond that’s predicted to be harder than a jeweller’s diamond and useful for cutting through ultra-solid materials on mining sites. ANU Associate Professor Jodie Bradby said her team – including ANU PhD student Thomas Shiell and experts from RMIT, the University of Sydney and the United States – made nano-sized Lonsdaleite, which is a hexagonal diamond only found in nature at the site of meteorite impacts such as Canyon Diablo in the US.

diamond

This new diamond is not going to be on any engagement rings. You’ll more likely find it on a mining site – but I still think that diamonds are a scientist’s best friend. Any time you need a super-hard material to cut something, this new diamond has the potential to do it more easily and more quickly,” said Dr Bradby from the ANU Research School of Physics and Engineering.

Her research team made the Lonsdaleite in a diamond anvil at 400 degrees Celsius, halving the temperature at which it can be formed in a laboratory. “The hexagonal structure of this diamond’s atoms makes it much harder than regular diamonds, which have a cubic structure. We’ve been able to make it at the nanoscale and this is exciting because often with these materials ‘smaller is stronger‘.”

Lonsdaleite is named after the famous British pioneering female crystallographer Dame Kathleen Lonsdale, who was the first woman elected as a Fellow to the Royal Society.

The research is published in Scientific Reports.

Source: http://www.anu.edu.au/

Nano-enhanced Textiles Clean Themselves Of Stains

Researchers at RMIT University in Melbourne, Australia, have developed a cheap and efficient new way to grow special —which can degrade organic matter when exposed to lightdirectly onto . The work paves the way towards nano-enhanced textiles that can spontaneously clean themselves of stains and grime simply by being put under a light bulb or worn out in the sun. Dr Rajesh Ramanathan said the process developed  by the team had a variety of applications for catalysis-based industries such as agrochemicals, pharmaceuticals and natural products, and could be easily scaled up to industrial levels.

no more washing textileClose-up of the nanostructures grown on cotton textiles by RMIT University researchers. Image magnified 150,000 times

The advantage of textiles is they already have a 3D structure so they are great at absorbing light, which in turn speeds up the process of degrading organic matter,”said Dr Ramanathan. “There’s more work to do to before we can start throwing out our washing machines, but this advance lays a strong foundation for the future development of fully self-cleaning textile, he adds.”

The researchers from the Ian Potter NanoBioSensing Facility and NanoBiotechnology Research Lab at RMIT worked with copper and silver-based nanostructures, which are known for their ability to absorb visible light.

Source: http://phys.org/

Towards The Bionic Brain

RMIT University (Australia) researchers have brought ultra-fast, nano-scale data storage within striking reach, using technology that mimics the human brain. The researchers have built a novel nano-structure that offers a new platform for the development of highly stable and reliable nanoscale memory devices, useful for nanocomputers. Project leader Dr Sharath Sriram, co-leader of the RMIT Functional Materials and Microsystems Research Group, said the nanometer-thin stacked structure was created using thin film, a functional oxide material more than 10,000 times thinner than a human hair.

Brain Cells
The thin film is specifically designed to have defects in its chemistry to demonstrate a ‘memristive‘ effect – where the memory element’s behaviour is dependent on its past experiences,” Dr Sriram said. “With flash memory rapidly approaching fundamental scaling limits, we need novel materials and architectures for creating the next generation of non-volatile memory. “The structure we developed could be used for a range of electronic applications – from ultrafast memory devices that can be shrunk down to a few nanometers, to computer logic architectures that replicate the versatility and response time of a biological neural network. “While more investigation needs to be done, our work advances the search for next generation memory technology can replicate the complex functions of human neural system – bringing us one step closer to the bionic brain.

The pioneering work will be published in the journal Advanced Functional Materials (11 November).

Source: http://www.rmit.edu.au

Hydrogen To Replace Lithium-Ion Battery

The novel concept developed by researchers at RMIT University – Australia -advances the potential for hydrogen to replace lithium as an energy source in battery-powered devices.

The proton flow battery concept eliminates the need for the production, storage and recovery of hydrogen gas, which currently limit the efficiency of conventional hydrogen-based electrical energy storage systems.

Lead researcher Associate Professor John Andrews, from RMIT‘s School of Aerospace, Mechanical and Manufacturing Engineering, said the novel concept combined the best aspects of hydrogen fuel cells and battery-based electrical power.

As only an inflow of water is needed in charge mode – and air in discharge mode – we have called our new system the ‘proton flow battery,” Associate Professor Andrews said.

Powering batteries with protons has the potential to be a much more economical device than using lithium ions, which have to be produced from relatively scarce mineral, brine or clay resources”. “Hydrogen has great potential as a clean power source and this research advances the possibilities for its widespread use in a range of applications – from consumer electronic devices to large electricity grid storage and electric vehicles“, he added.

Source: http://www.rmit.edu.au