Graphene-enhanced fluid improves solar collectors' efficiency

Researchers at the University of Lisbon's Centro de Química Estrutural have discovered that the addition of graphene to the working fluid of solar collectors helps to regain some of its lost efficiency. Solar thermal collectors are seen as a simple and inexpensive way to make use of solar energy. Pure water is an efficient heat-transfer fluid, but it must be mixed with antifreeze to prevent damage to pipes during freezing conditions, and this lowers its performance.

Graphene enhances the performance of solar collectors image

The properties of an ideal heat-transfer fluid in a solar collector include a high thermal capacity and a freezing point outside of the temperature range likely to be encountered. Unfortunately, in the case of water, satisfying the latter requirement means compromising on the former, as mixing water with antifreeze makes it a less effective carrier of heat.

NSF grant to fund development of inkjet-printed graphene-based water quality sensors

The National Science Foundation recently awarded University of Wisconsin-Milwaukee scientists $1.5 million to perfect a method of mass-producing graphene-based small water sensors using inkjet printing. The goal is to determine whether the process can be customized in order to scale up production and in a more economic way than traditional manufacturing methods.

Inkjet-printed graphene-based water quality sensors image

The graphene-based sensors, developed at UWM, reportedly outperform current technologies in accuracy, sensitivity and sensing speed. Their performance and size make them useful for continuously monitoring drinking water for miniscule traces of contaminants like lead.

Grolltex announces new CVD graphene facility

Grolltex logo imageGrolltex, a U.S-based advanced materials and equipment company, recently announced a large-capacity commercial lab for production of high quality CVD graphene. Grolltex states that it is now manufacturing the material in its new class 1000 clean room, producing both raw graphene as well as products made from the material, like sensors, perovskite solar cells, display materials and X-ray windows for use in spacecraft.

The new Grolltex graphene facility is said to be capable of producing large high-quality sheets of graphene for commercial sale. The Company is said to have a patented methodology to manufacture the material in a novel way that yields lower-cost materials of high quality. Grolltex leverages graphene research and patents developed at nearby University of California, San Diego.

MIT team creates flexible, transparent solar cells with graphene electrodes

Researchers at the Massachusetts Institute of Technology (MIT) have developed flexible and transparent graphene-based solar cells, which can be mounted on various surfaces ranging from glass to plastic to paper and tape. The graphene devices exhibited optical transmittance of 61% across the whole visible regime and up to 69% at 550 nanometers. The power conversion efficiency of the graphene solar cells ranged from 2.8% to 4.1%.

MIT team's flexible, transparent solar cell with graphene electrodes image

A common challenge in making transparent solar cells with graphene is getting the two electrodes to stick together and to the substrate, as well as ensuring that electrons only flow out of one of the graphene layers. Using heat or glue can damage the material and reduce its conductivity, so the MIT team developed a new technique to tackle this issue. Rather than applying an adhesive between the graphene and the substrate, they sprayed a thin layer of ethylene-vinyl acetate (EVA) over the top, sticking them together like tape instead of glue.

Graphene Flagship team creates transistors printed with graphene and other layered materials

Graphene Flagship researchers from AMBER at Trinity College Dublin, in collaboration with scientists from TU Delft, Netherlands, have fabricated printed transistors consisting entirely of layered materials. The team's findings are said to have the potential to cheaply print a range of electronic devices from solar cells to LEDs and more.

The team used standard printing techniques to combine graphene flakes as the electrodes with other layered materials, tungsten diselenide and boron nitride as the channel and separator to form an all-printed, all-layered materials, working transistor.

Versarien - Think you know graphene? Think again!Versarien - Think you know graphene? Think again!