How to Produce Graphene from Carbon Dioxide?

The combustion of fossil fuels like coal and oil produce energy for electricity, heat and mobility. But this also leads to a raise in the amount of carbon dioxide in the atmosphere and, therefore, to global warming. Cutting this causal chain is what motivates scientists to look for alternative energy sources, but also alternative uses of carbon dioxide. There could be one possibility for seeing carbon dioxide as an inexpensive raw material for the synthesis of valuable materials, returning it to the reuse cycle, even in a cost-effective way.

An example can be found in nature. During the process of photosynthesis in the leaves of plants, the combination of light, water and carbon dioxide creates biomass, closing the natural material cycle. In this process, the work of the metal-based RuBisCo enzyme is to absorb carbon dioxide from the air and make it usable for additional chemical reactions in the plant. Inspired by this natural conversion based on metal enzymes, KIT researchers now present a process in which the carbon dioxide of the greenhouse gas along with the hydrogen gas is converted directly into graphene at temperatures of up to 1000 degrees Celsius with the aid of specially prepared catalysts of active metal surfaces.

Graphene is the two-dimensional form of the chemical element carbon, which has interesting electrical properties and, so, is an option for new future electronic components. His discovery and ability to work in 2004 led to intensive research around the world and earned him the discoverers. Andre Geim and Konstanin Novoselov won the Nobel Prize in Physics in 2010. The two manually removed the graphene from a block of graphite with tape.

Many working groups in KIT have combined for presenting a method in the journal ChemSusChem to separate graphene from carbon dioxide and hydrogen by means of a metallic catalyst. "If the metal surface reflects the correct ratio of copper and palladium, the conversion of carbon dioxide to graphene will be done directly in a simple one-step process," explains the head of the study, Professor Mario Ruben, from Molekulare Materialien, group at the Institute of Nanotechnology (INT) and the Institute of Inorganic Chemistry (AOC) at KIT. In additional experiments, the researchers were even able to produce graphene of several layers of thickness, which could be interesting for possible applications in batteries, electronic components or filter materials. The next research objective of the working group is to form electronic components that work from the graphene thus obtained. Carbon materials, like graphene and magnetic molecules, could be the building blocks for future quantum computers, which allow for ultra-fast and energy-efficient calculations, but are not based on the binary logic of today's computers.

By: Preeti Narula

Content: https://www.sciencedaily.com/releases/2019/07/190708122340.htm