Graphene sensors: introduction and market status - Page 16

University of Illinois researchers have used graphene to develop a rapid, ultrasensitive test using a paper-based electrochemical sensor that can detect the presence of the virus in less than five minutes.

Currently, we are experiencing a once-in-a-century life-changing event, said bioengineering graduate student and co-leader of the study, Maha Alafeef. We are responding to this global need from a holistic approach by developing multidisciplinary tools for early detection and diagnosis and treatment for SARS-CoV-2.

An international team of researchers, led by Huanyu "Larry" Cheng, a Professor at Penn State, has used graphene to design a stretchable system that can harvest energy from human breathing and motion for use in wearable health-monitoring devices.

According to Cheng, current versions of batteries and supercapacitors powering wearable and stretchable health-monitoring and diagnostic devices have many shortcomings, including low energy density and limited stretchability. "This is something quite different than what we have worked on before, but it is a vital part of the equation," Cheng said, noting that his research group and collaborators tend to focus on developing the sensors in wearable devices. "While working on gas sensors and other wearable devices, we always need to combine these devices with a battery for powering. Using micro-supercapacitors gives us the ability to self-power the sensor without the need for a battery."

Paragraf, UK-based graphene electronic sensors and devices company, announced that it is helping to realize an industry first by implementing a supply chain for graphene Hall-Effect sensors used in high-temperature Power Electronics, Electric Machines and Drives (PEMD) within the aerospace sector.

Named High-T Hall, the project stems from the UK Research and Innovation’s (UKRI) ‘Driving the Electric Revolution’ challenge and brings together Paragraf, Rolls-Royce, TT Electronics (Aero Stanrew) and the Compound Semiconductor Applications Catapult (CSA Catapult). It is set to demonstrate how graphene-based Hall Effect sensors can operate reliably at high temperatures, paving the way for more efficient electric engines in aerospace and beyond.

Archer Materials has announced that it has started building its lab-on-chip biosensing device, A1 Biochip, which could potentially be capable of simplifying disease detection. According to Archer, it will be designing and building its own biochip, which means it will no longer need prototyping sensor materials, graphene inks, 2D/3D printing, or circuit boards.

Developing the biochip product will speed up the commercialization of the biochip.

Integrated Graphene (formerly known as RD Graphene), developers of hyper-sensitive 3D graphene foam electrodes, have set their aims on the human diagnostics market and are aiming to enable better biosensors with improved performance and speed. The company has launched its flagship 3D graphene foam process in their first product, Gii-Sens.

The company launched its first product in conjunction with its new Integrated Graphene brand, in hopes that these steps will mark the first steps on an ambitious commercial journey to establish themselves as a leading producer of pure 3D graphene foam. In addition, the Company led a funding round in which it has raised £3.1 million (almost USD$4 million). This latest investment round follows £300,000 in seed funding from six private investors in March 2019, plus a variety of grant funding totaling £1.8m raised since 2014.

An international team of researchers recently reported its success in creating a new type of graphene-based photodetector.

The team integrated three concepts to achieve the new device: metallic plasmonic antennas, ultra sub-wavelength waveguiding of light and graphene photodetection. Specifically, the 2D-material hexagonal boron nitride was used as the waveguide for hyperbolic phonon polaritons, which can highly confine and guide mid-infrared light at the nanoscale. By carefully matching the nano-antenna with the phonon polariton waveguide, they efficiently funnel incoming light into a nanoscale graphene junction. By using this approach, they were able to overcome intrinsic limitations of graphene, such as its low absorption and its small photoactive region near the junction.

An interdisciplinary team of researchers from The University of Manchester have developed a new graphene-based testing system for disease-related antibodies, initially targeting a kidney disease called Membranous Nephropathy.

The new instrument, based on the principle of a quartz-crystal microbalance (QCM) combined with a graphene-based bio-interface, is said to offer a cheap, fast, simple and sensitive alternative to currently available antibody tests.

Scientists from Russia and Germany have created a graphene-based broadband detector of terahertz radiation. The device could have potential for applications in communication and next-generation information transmission systems, security and medical equipment.

(a) shows a top view of the device, with the sensitive region magnified in (b). The labels S, D, and TG denote the source, drain, and top gate. A side section of the detector is shown in (c). Image from MIPT

The new detector relies on the interference of plasma waves. Plasma waves in metals and semiconductors have recently attracted much attention from researchers around the world. Like the more familiar acoustic waves, the ones that occur in plasmas are essentially density waves, too, but they involve charge carriers: electrons and holes. Their local density variation gives rise to an electric field, which nudges other charge carriers as it propagates through the material. This is similar to how the pressure gradient of a sound wave impels the gas or liquid particles in an ever expanding region. However, plasma waves die down rapidly in conventional conductors.

Researchers from the Daegu Gyeongbuk Institute of Science and Technology in South Korea have recently developed a low-cost energy storage device to power electronic devices like wearable skin sensors. The supercapacitor, made with graphene ink that is sprayed onto flexible substrates, can be used for remote medical monitoring and diagnosis on wearable devices.

Materials scientist Sungwon Lee shared that as the demand for wearable devices and remote diagnosis has increased, scientists have focused on developing electronic skin devices. The team focused on "extremely tiny and flexible energy devices as a power source."

A joint international research team, including teams from POSTECH of South Korea, Raytheon BBN Technologies, Harvard University, and Massachusetts Institute of Technology in the U.S., Barcelona Institute of Science and Technology in Spain, and the National Institute for Materials Science in Japan, has developed ultrasensitive sensors that can detect microwaves with the highest theoretically possible sensitivity. The research findings are drawing attention as an enabling technology for commercializing next-gen technologies like quantum computers.

Microwave bolometer based on graphene josephson junction. Image credit: Raytheon BBN Technologies and MIT

Microwave is used in a wide range of scientific and technological fields, including mobile communications, radar, and astronomy. Currently, microwave power can be detected using a device called bolometer. A bolometer usually consists of three materials: Electromagnetic absorption material, a material that converts electromagnetic waves into heat, and a material that converts the generated heat into electrical resistance. The bolometer calculates the amount of electromagnetic waves absorbed using the changes in the electrical resistance. Using the semiconductor-based diodes such as silicon and gallium arsenide in the bolometer, the sensitivity of the state-of-the-art commercial bolometer operating at room temperature is limited at 1 nanowatt (1 billionth of a watt) by averaging for a second.