New Quality Control for 'Wonder Material' Graphene Oxide is Cheapest and Fastest Yet

Researchers have developed a new approach to characterising graphene oxide (GO) that significantly reduces time and cost, potentially accelerating the material’s transition from laboratory research to commercial applications.

A team at King’s College London has designed an “interactional fingerprinting” method that assigns a unique identity to individual samples. Inspired by the human senses of taste and smell, the technique produces a qualitative snapshot of GO without relying on expensive, specialised equipment that typically requires highly trained operators.

This advancement offers a more accessible means of quality control for GO, which could help address current barriers to its widespread use in sustainable electronics and cleaner battery technologies.

Interest in graphene-based materials has grown substantially since researchers in Manchester received the 2010 Nobel Prize in Physics for their work on graphene. The material’s light weight, strength, and high conductivity have driven major investments, including £180 million from the Graphene Engineering Innovation Centre and the National Graphene Institute, to develop products such as advanced batteries and body armour using GO and related materials.

Despite this potential, large-scale deployment beyond research settings has been slow. A 2018 study identified inconsistent supply and unreliable testing conditions as major challenges, noting that “producers are labeling black powders as graphene and selling for top dollar.” For GO in particular, the incorporation of varying oxygen types into single-atom graphene flakes can create even greater variability. The same research group observed that only a small proportion of GO products “deliver approximately what they display on the label or brochure.”

Existing gold-standard characterisation methods can cost up to £5000 per sample and take a month to complete, making them inaccessible for many research and industrial settings due to the expense and scarcity of the required equipment.

The new method employs a first-of-its-kind molecular probing device to assess GO at a fraction of the conventional cost and time. According to Dr Andrew Surman, Senior Lecturer in Chemistry at King’s College London, “Graphene oxide is really promising. But if we’re to make good progress, we need to confirm that a new batch is like the last one. If your supply is unreliable – and behaves differently every time – how do you go about designing better products? Commercial services to test a new batch are expensive and can take weeks. That’s not often feasible.”

He added, “Our approach should allow researchers and materials producers to perform a test in a couple of hours, using cheap tools they likely already have access to, to quickly quality control their samples where they work. By helping teams troubleshoot variation in their supply it helps ensure what they are working with is up to scratch, freeing them up for the important business of innovation in next-generation technology.

The method, detailed in the Journal of the American Chemical Society, involves mixing small water-dispersed GO samples with a series of molecular probes that fluoresce until they interact with the material’s surface. These probes are tuned to detect key characteristics such as oxygen content and flake size. By mapping fluorescence changes mathematically, the researchers generate an “interactional fingerprint” that can distinguish between different types of GO, including those with low oxygen levels.

As the device is material agnostic, the team anticipates that this probe-based approach could be applied to other advanced materials, such as borophene, to support their progression from research environments into commercial markets.

source : Advanced Carbons Council