A novel method for synthesizing graphene oxide has been discovered by Umeå researchers, and the resulting materials have much fewer flaws than those made using the most popular approach.
Alexandr Talyzin and his research group at the Department of Physics have developed a new method to synthesize graphene oxide. Image Credit: Mattias Pettersson
Previously, only a highly hazardous process requiring extremely toxic fuming nitric acid could produce graphene oxide of similar quality.
Graphene is frequently made by eliminating oxygen using graphene oxide. However, after graphene oxide is transformed into graphene, any hole present remains in the graphene. Consequently, the graphene oxide's purity is crucial. Now, Alexandr Talyzin and his team at Umeå University have solved the riddle of producing high-quality graphene oxide in a safe manner. The scientific journal Carbon just published its results.
Graphene is commonly referred to as a “wonder material” due to its flexibility, great mechanical strength, and conductivity. However, imperfections impact all of graphene’s characteristics. The mechanical characteristics and conductivity of graphene generated from graphene oxide are far worse than predicted.
Too Dangerous for Industrial Manufacturing
Many investigations have shown that synthesis using the most often used approach, the Hummers method, invariably produces a high percentage of faults. The much earlier Brodie process produces virtually hole-free graphene oxide, but no companies make it, and it is not commercially accessible.
It is simply too dangerous and not suitable for industrial manufacturing.
Alexandr Talyzin, Professor, Department of Physics, Umeå University
Researchers from Umeå discovered an innovative approach that utilizes the acid from the Hummers method (H2SO4) and the oxidant from the Brodie method (potassium chlorate), enabling them to generate graphene oxide with flaws as small as those in the Brodie method but employing a synthesis procedure as simple as Hummers oxidation.
Talyzin further added, “This method should be named after Bartosz Gurzeda, a researcher working in my group with the help of the Kempe Stipendium, as the Gurzeda method.”
Can Be Used for Water Treatment
According to Alexandr Talyzin, the Gurzeda process is likely to become as common as Hummers oxidation anytime defect-free graphene oxide is required. This is used to create graphene by removing oxygen groups, as well as to prepare gas protection coatings, semi-permeable membranes, sensors, and a wide range of other uses.
In the last decade, there has been a lot of interest in the uses of graphene oxide. Layered graphene oxide materials are being extensively researched for membrane applications, with the goal of producing drinkable water through simple filtration of salts from seawater or developing semi-permeable protective coatings that enable water to pass while maintaining dangerous organic pollutants, such as toluene, at bay.
Talyzin concluded, “We want the research society to try and test this new graphene oxide in their applications and see the difference. Graphene oxide is not one material; it is a family of materials with rather different properties, providing us with infinite opportunities for new applications.”
Journal Reference:
Gurzęda, B., et. al. (2024) Graphite oxide by “chlorate route” oxidation without HNO3: Does acid matter? Carbon. doi:10.1016/j.carbon.2024.118899.