Crumpled graphene may benefit self-cleaning surfaces and batteries

Researchers at Brown University have demonstrated that graphene, wrinkled and crumpled in a multi-step process, becomes significantly better at repelling water - a property that could be useful in making self-cleaning surfaces. Crumpled graphene also has enhanced electrochemical properties, which could make it more useful as electrodes in batteries and fuel cells.

The researchers aimed to build relatively complex architectures incorporating both wrinkles and crumples. To do that, the researchers deposited layers of graphene oxide onto shrink films -polymer membranes that shrink when heated. As the films shrink, the graphene on top is compressed, causing it to wrinkle and crumple. To see what kind of structures they could create, the researchers compressed same graphene sheets multiple times. After the first shrink, the film was dissolved away, and the graphene was placed in a new film to be shrunk again.

Seamlessly bonded graphene and CNTs form a 3D material that maintains conductivity

In a research funded by a U.S. Department of Defense-Multidisciplinary University Research Initiative grant and Wenzhou Medical University, an international team of scientists has developed what is referred to as the first one-step process for making seamless carbon-based nanomaterials that possess superior thermal, electrical and mechanical properties in 3D. The research may hold potential for increased energy storage in high efficiency batteries and supercapacitors, increasing the efficiency of energy conversion in solar cells, for lightweight thermal coatings and more. 

The group's early testing showed that a 3D fiber-like supercapacitor made with uninterrupted fibers of carbon nanotubes and graphene matched or even surpassed bettered the reported record-high capacities for such devices. When tested as a counter electrode in a dye-sensitized solar cell, the material enabled the cell to convert power with up to 6.8% efficiency and more than doubled the performance of a similar cell that used an expensive platinum wire counter electrode. 

Spanish university develops graphene-based catalysts for the energy industry

Researchers at the Spanish Universitat Jaume I have developed graphene-based materials that can catalyse reactions for the conversion and storage of energy. The technology combines graphene and organometallic compounds in a single material without altering graphene's properties like electrical conductivity.

The technology is expected to be of great interest to the energy industry and is part of what is known as "hydrogen economy", an alternative energetic model in which energy is stored as hydrogen. In this regard, the materials (patented by the UJI) allow catalysing reactions for obtaining hydrogen from alcohols and may also serve as storage systems of this gas.

Israeli and Australian scientists come up with a fast and efficient method of producing graphene

Researchers at the Israeli Ben-Gurion University of the Negev (BGU) and University of Western Australia have designed a new process for creating few-layer graphene for use in energy storage and other material applications that is faster, potentially scalable and surmounts some of the current graphene production limitations.

The new one-step, high-yield generation process is based on an ultra-bright lamp-ablation method and has succeeded in synthesizing few-layer (4-5) graphene in relatively high yields. It involves a novel optical system (originally invented by BGU professors) that reconstitutes the immense brightness within the plasma of high-power xenon discharge lamps at a remote reactor, where a transparent tube filled with simple, inexpensive graphite is irradiated. The process is considered fast, safe and green (free of any toxic substances - just graphite plus concentrated light).

LFP battery cathode improved by using graphene

Researchers at the Harbin Institute of Technology in China and the University of Michigan in the US demonstrated improved LFP battery cathode, augmented by reduced graphene oxide. The scientists used reduced graphene oxide (rGO) in LFP battery cathodes to create a new high surface area 3D composite.

LFP (or LiFePO4) is a kind of Li-Ion rechargeable battery for high power applications, such as electric vehicls, Power Tools and more. LFP cells feature high discharging current, non explosive nature and long cycle life, but its energy density is lower than normal Li-Ion cell. In this study, the researchers created the composite using a nickel foam template that was coated with layers of graphene oxide. The graphene oxide reduced as the LFP nanoparticles were synthesized in a simple technique that allows larger amounts of the LFP to be loaded into the carbon material.

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