Graphene NEMS switch for electrostatic discharge protection applications

Researches from the University of California, Riverside and University of California, Los Angeles have demonstrated a novel above-IC graphene NEMS switches for electrostatic discharge (ESD) protection applications.

Graphene NEMS switch for electrostatic discharge protection applications image

This graphene ESD switch is a two-terminal device with a gap between the conducting substrate at the bottom and a suspended graphene membrane on top serving as the discharging path. This new concept provides a potentially revolutionary mechanism for the on-chip ESD protections.

Read the full story Posted: Nov 28,2018

UCLA team designs a novel type of graphene-based photodetector

Engineers from the UCLA have Used graphene to design a new type of photodetector that can work with more types of light than its current state-of-the-art counterparts. The device also has superior sensing and imaging capabilities.

UCLA's novel graphene-based photodetector image

photodetectors' versatility and usefulness depend largely on three factors: their operating speed, their sensitivity to lower levels of light, and how much of the spectrum they can sense. Typically, when engineers have improved a photodetector’s capabilities in any one of those areas, at least one of the two other capabilities has been diminished. The photodetector designed by the UCLA team has major improvements in all three areas it operates across a broad range of light, processes images more quickly and is more sensitive to low levels of light than current technology.

Read the full story Posted: Jun 28,2018

New tree-inspired electrodes could boost supercapacitors’ performance

Researchers from the UCLA, Mississippi State University, University of Nevada and China's Central South have designed an efficient and long-lasting graphene-based electrode for supercapacitors. The device’s design was inspired by the structure and function of leaves on tree branches, and it is said to be more than 10 times more efficient than other designs.

An efficient and long-lasting graphene-based electrode for supercapacitors image

The electrode design reportedly provides the same amount of energy storage, and delivers as much power as similar electrodes, despite being much smaller and lighter. In experiments it produced 30% better capacitance — a device’s ability to store an electric charge — for its mass compared to the best available electrode made from similar carbon materials, and 30 times better capacitance per area. It also produced 10 times more power than other designs and retained 95% of its initial capacitance after more than 10,000 charging cycles.

Read the full story Posted: Feb 26,2018

A graphene-based device reveals the dynamics of single-molecule reactions

A team of international researchers has made a graphene-based device that captures the real-time dynamics of a classic chemical reaction at the single molecule level. Developed at Peking University, UCLA and the Institute Chinese Academy of Sciences, the method could shed light on the mechanism of chemical and biological processes.

Graphene device reveals step-by-step dynamics of single-molecule reaction image

The device consists of two graphene arrays that flank a single molecule covalently tied to each array through amide linkers. The molecule, 9-fluorenone, contains a carbonyl group situated astride three fused rings. The team submerged the device in a solution containing a catalyst and the reagent hydroxylamine, which reacts with 9-fluorenone’s carbonyl group. The reaction changes the electrical charge of 9-fluorenone, so the team could follow the nucleophilic addition reaction by monitoring current conducted by the graphene arrays.

Read the full story Posted: Feb 15,2018

Graphene-based biological supercapacitors may enable improved pacemakers and implantable medical devices

Researchers from UCLA and the University of Connecticut have designed a biological supercapacitor which operates using ions derived from bodily fluids. The team predicts that this work could lead to longer-lasting cardiac pacemakers and other implantable medical devices.

The biosupercapacitor, which features graphene layered with modified human proteins as an electrode, could be used in next-generation implantable devices to speed bone growth, promote healing or stimulate the brain.

Read the full story Posted: May 24,2017

Graphene barrier allows precise control over molecules for creation of nanoelectronics

Scientists from UCLA’s California NanoSystems Institute have designed an effective way to use graphene in order to place molecules specific patterns within tiny nanoelectronic devices, which could be useful in creating sensors that are even small enough to record brain signals.

This is done by using a sheet of graphene with minuscule holes in it that is then placed on a gold substrate. The holes allow molecules to attach to the gold exactly where the scientists want them, creating patterns that control the physical shape and electronic properties of devices that are 10,000 times smaller than the width of a human hair.

Read the full story Posted: Jan 20,2016

UCLA scientists combine graphene with manganese oxide to create innovative supercapacitors

Researchers at UCLA’s California NanoSystems Institute have successfully combined laser-scribed graphene and manganese dioxide (which is currently used in alkaline batteries since it holds a lot of charge and is cheap and abundant) to create a new energy storage device with outstanding qualities. The new hybrid supercapacitor stores large amounts of energy, recharges quickly, and can last for more than 10,000 recharge cycles.

The scientists also created a microsupercapacitor that is small enough to fit in wearable or implantable devices. At just a fifth of the thickness of a sheet of paper, it can hold more than twice as much charge as a typical thin-film lithium battery.

Read the full story Posted: Apr 03,2015

New holey graphene network enables supercapacitors with highest energy density

Researchers from the UCLA developed a new graphene-based material that can significantly enhance the energy density of supercapacitors - in fact making them as good as lead acid batteries.

They call the new material holey graphene framework. It is a 3D material that has tiny holes in it. The holey graphene features superior electrical conductivity, exceptional mechanical flexibility and unique hierarchical porosity. This enabled the researchers to create a capacitor that has an unparalleled energy densities of 35 watt hours per kilogram (49 watt hours per liter), which is up to 10 times higher than current commercial supercapacitors.

Read the full story Posted: Aug 13,2014

UCLA enhances their laser-scribed graphene supercapacitor technology, ready for commercialization

Back in March 2012 we posted about a UCLA research that developed laser-scribed graphene (LSG) based flexible capacitors using simple DVD burners. Now those same researchers have published a new paper describing an new structural design, which makes the capacitors compatible with other integrated circuits and enhances their capacity and speed. They are now looking for industrial partners to commercialize the technology.

Their original design stacked graphene layers to create the electrode, which was not compatible with integrated circuits. The new design uses a side-by-side electrode placement which helps to maximize the accessible surface area available for the electrodes while also reducing the path over which ions in the electrolyte would need to diffuse. The new capacitors have a higher charge capacity and rate capability.

Read the full story Posted: Feb 26,2013