Linköping researchers make progress in using graphene to make fuel from water and carbon dioxide

Researchers at Linköping University (LiU) in Sweden are working to develop a method to convert water and carbon dioxide to the renewable energy of the future, using the energy from the sun and graphene applied to the surface of cubic silicon carbide.

The LiU research group recently reported an important step towards achieving this goal, and developed a method that makes it possible to produce graphene with several layers in a tightly controlled process. They have also shown that graphene acts as a superconductor in certain conditions.

Researchers find the exact balance in which graphene coatings can promote hydrogen evolution reaction

A collaboration led by the University of Tsukuba has recently optimized an approach to increase the stability of catalysts used in the hydrogen evolution reaction without significantly sacrificing activity. The team found that coating catalyst nanoparticles with an optimal number of layers of graphene raised nanoparticle durability while allowing the nanoparticles to retain their catalytic activity. The study was reported in ACS Energy Letters.

"We optimized the balance between the number of graphene layers coating the nanoparticles and their catalytic activity," study first author Kailong Hu says. "To do this, we had to precisely control the number of graphene layers coating the nanoparticles, which we achieved by carefully regulating the deposition time of graphene on the nanoparticles."

Japanese team designs a graphene-based electrode that can produce hydrogen under acidic conditions

Researchers at the Japanese Tsukuba University described a graphene-based electrode that can produce hydrogen under acidic conditions. The electrolysis of water to generate hydrogen is vital for energy storage in a green economy. One of the major obstacles, however, is the high cost of noble-metal electrodes. Cheaper non-noble electrodes function well in driving the hydrogen evolution reaction (HER), but mainly in alkaline conditions, where the reaction is electricity-hungry. The more efficient acid-phase reaction requires precious metals such as platinum. Worse still, the acid electrolytes are corrosive and eat away at the core metal.

Perforated graphene for hydrogen production image

The researchers have found that holey graphene offers a way around this problem. They used nitrogen-doped graphene sheets to encapsulate a nickel–molybdenum (NiMo) electrode alloy. The graphene was punched full of nanometer-size holes. The researchers showed that in acid conditions, their HER system dramatically outperforms an electrode using regular non-holey graphene. The use of graphene in HER electrodes is not new—this flexible, conductive carbon sheet is ideal for wrapping around the core metal. However, although it protects the metal against corrosion, graphene also suppresses its chemical activity. In the Tsukuba system, the holes promote the reaction in two ways, while the intact graphene part protects the metal.

University of Warsaw team develops a graphene-matrix with potential for medicine and food applications

Researchers at the Department of Chemistry of the University of Warsaw in Poland have developed a new graphene matrix, as a functional substrate for immobilizing enzymes, and the method of its preparation. The newly-patented graphene matrix may find applications in the food and medicine industries, like the production of biosensors and other electronic devices (eg. bands, tattoos).

A graphene matrix for applications in the food industry and medicine for the production of biosensors imageDiagram of a lactate biosensor composed of a graphene matrix and a lactate oxidase enzyme, deposited on a carbon electrode

The invention is used as a stable system with high sensitivity, not only in analytical biosensors, but also in bio-fuel cells used in medicine, biology and chemical biocatalysis. The solution concerns the enzymatic (protein) sensor construction for detection of lactates, which can be used in the food industry and medicine for the production of biosensors.

XFNano graphene materials used in advanced energy application research

The following is a sponsored post by XFNano

XFNano's graphene materials were recently used in two fascinating research work focused on advanced energy applications.

NiCo-HS@G fabrication (XFNano)

The first is a work by teams from Anhui Normal University, Chinese Academy of Sciences (CAS) and the University of the Chinese Academy of Sciences which developed a fast, one-step strategy to prepare sandwiched metal hydroxide/graphene composites through a kinetically controlled coprecipitation under room temperature. Such NiCo-HS@G nano-composite exhibits good electrocatalytic activity for OER, superior to most of the reported OER catalysts. Such performance and the facile preparation of NiCo-HS@G opens up a new avenue for the cost-effective and low-energy-consumption production of various sandwiched metal hydroxides/graphene composites as efficient OER electrocatalysts with desired morphology and competing performance for the applications in diverse energy devices.