Modified graphene sensors could pave the way for a new level of safety and convenience across multiple industries. This unique modification process enhances graphene’s gas detection capabilities, opening the door for more robust safety systems like wearable gas sensors. Here’s how modified graphene sensors could become indispensable tools in the future.
Gas Sensors
Gas sensors are found across a multitude of industries. They play a crucial role in keeping systems safe. These devices can be found in workplaces, homes, medical facilities, and even in outside conditions where they monitor harmful gas emissions.
How Gas Sensors Work?
Several gas sensors are in use today, with the main variants being semiconductor, IR, and electrochemical options. Each of these sensor designs brings pros and cons, making them ideal for certain use-case scenarios.
Semiconductor
Semiconductor gas sensors are the most common. This gas sensor design leverages a gas-absorbing metal oxide surface to monitor levels. The surface undergoes a redox reaction when exposed to certain gases, resulting in a measurable change in resistance.
IR (Infrared)
Infrared gas monitoring systems utilize an invisible beam of light to determine the presence of harmful gases. Interestingly, these systems can measure the amount of IR rays the gas molecules absorb. Since this method can be fine-tuned to different weave lengths, it’s ideal for scientific purposes.
Electrochemical
The final type of gas sensor commonly used in the market is an electrochemical sensor. This option leverages oxidation-reduction reactions to measure gas concentration. As these reactions occur, they produce a current that can be tracked and registered.
Graphene-Based Materials
The latest and most advanced form of gas sensing systems available today leverage carbon nanomaterials like graphene. Graphene-based materials offer a host of benefits, including that they are inexpensive, versatile, require minimal power, and can operate at room temperature. Additionally, they can be arranged to create 2D structures.
Problems with Today’s Gas Sensors
Despite the major upgrade that gas sensors have undergone in the last decades, there’s still lots of room for improvement. These devices continue to have limitations in sensitivity, responsibility, and energy efficiency. Thankfully, a new study sheds light on how to improve these limitations and create next-generation gas sensing systems.
Modified Graphene Sensors Study
The “Graphene Functionalization by O2, H2, and Ar Plasma Treatments for Improved NH3 Gas Sensing“1 published in ACS Applied Materials & Interfaces introduces a novel plasma-modification method that enhances graphene-based sensor capabilities. Specifically, it creates structural and chemical defects that boost chemical detection.
Functionalized Graphene Sheets
At the core of the study is the concept of functionalized graphene. Functionalized refers to attaching specific chemical groups to the substance and adding controlled defects to enhance capabilities.
In this scenario, engineers choose three main gases to work with: argon (Ar), hydrogen (H2), and oxygen (O2). The group utilized these chemical environments to create specific carbon vacancies and oxidation sites based on formulations showing increased gas sensitivity.
Target Gases
The study focused on the harmful chemical compound ammonia (NH3). Ammonia forms from hydrogen and nitrogen and is a vital precursor for many natural chemical processes. Today, Ammonia is primarily used as a fertilizer and remains classified as extremely hazardous due to its explosive characteristics. These factors make ammonia detection a critical component of many industrial processes.
Chemical Clean Up
The engineers introduced multiple defects into the graphene to increase NH3 absorption and sensitivity. Notably, the use of different arrangements and strategies allowed the team to determine the most effective layout to enhance performance.
Modified Graphene Sensors Test
The engineers leveraged both spectroscopic measuring strategies and theoretical calculations to gain a detailed understanding of exactly what chemical changes occurred in the graphene. Additionally, the team was able to improve their results by tracking the precise structural and chemical changes in real time.
Test Results
Utilizing a Raman scattering spectroscopy, the team determined exactly how and why graphene sheets treated by plasma with different gases gain high sensitivity to certain gases. They determined that the NH3 can attach with less effort to the functionalized graphene versus its pristine counterpart.
O2
In the O2 environment, the team leverages plasma treatment-induced oxidation of the graphene. This strategy created a graphoxide. Notably, graphoxide had carbon vacancy-type defects, which demonstrated the greatest changes in sheet resistance.
Specifically, the team registered a 30% alteration. These results mean that O2-based modified graphene sensors are the most sensitive of the three types tested.
H2
The next testing environment was composed of H2 plasma. This interaction created graphene via induced hydrogenation. The team noted that this test showed sp3-type defects, meaning the carbon atoms in graphene formed four bonds in a tetrahedral design. When this scenario occurs, it improves performance.
Ar
Argon-treated graphene produced mixed results in that it showed both types of defects. Out of the three options, AR-treated graphene provides the lowest boost compared to traditional graphene sensors. Notably, all of the sensors showed changes in electric conductivity.
Benefits of the Study
There are many benefits that the study of modified graphene brings to the market. For one, improved safety systems can help save lives and the environment. Gas sensing systems are a critical component of the manufacturing and industrial economies. Any improvements in these systems can result in significant savings and a boost in capabilities, leading to the development of next-generation gas-sensing devices.
Thin Layers
Graphing provides a major advantage to other materials in that it can be made into 2D designs. The team created one of the thinnest possible sheets of graphene with gas permeability in the world. As such, this new graphene layer could open the door for the creation of more advanced safety systems.
Modified Graphene Sensors Applications
There are many applications for the next-generation gas detection systems. Functional graphene provides lightweight and durable performance that offers high functionality at low costs. As such, many see it as a game-changing material.
Personal Safety
One of the biggest applications for functionalized graphene is in the personal safety sector. Engineers envision a day where anyone can wear a harmful gas sensing system and get accurate insight into their environment. The thin and durable nature of graphene makes it the ideal material for use in wearables.
Industrial Safety
The industrial sector needs more accurate and reusable gas detection options. This latest study will open the door for more worker safety by making it more affordable and accessible to detect toxic and combustible gases.
Environmental
Utilizing graphene sensors will help environmentalists keep better tabs on pollution levels. Toxic gases continue to cause damage to the environment. As such, there is a strong effort to limit this population and prevent it from entering the atmosphere and creating ozone damage. Graphene sensors can be used to locate and help capture carbon monoxide, nitrogen oxides, hydrocarbons, and other harmful chemicals.
Healthcare
Healthcare researchers have looked at gas-sensing systems to help locate and diagnose diseases based on biomarkers. Biomarkers are certain chemicals that your body gives off when in the presence of certain diseases or ailments. They can be used to diagnose things like lung cancer, diabetes, kidney disease, and asthma.
Food
These sensors could make the food supply chain safer as well. When food decomposes, it releases volatile organic compounds (VOCs) that sensors can detect. In the future, high-performance gas sensing technology could ensure that your produce and meats are safe to eat.
Modified Graphene Sensors Researchers
The graphene sensors study was led by engineers from the Graduate School of Science, Chiba University, Japan. The main author is Associate Professor Tomonori Ohba. Additionally, Mr. Sogo Iwakami and Mr. Shunya Yakushiji contributed to the research. Now, the team seeks to expand research and find more applications for their high-performance gas-sensing functionalized graphene.
Companies Leading the Gas Sensing Industry
Many industries rely on accurate gas sensing equipment to operate. Consequently, the market is a billion-dollar sector that has major players vying for the top spot. Here’s one company that has secured a reputation as a reliable and pioneering option within the gas sensor sector.
Honeywell International Inc. (HON +0.78%) is a globally recognized gas systems manufacturer. The company has a long history that began in 1906 with the founding of Honeywell Heating Specialty Co.
Mark C. Honeywell founded the company intending to offer more reliable industrial monitoring options. In 1963, the company changed its name to Honeywell Inc. From there, it began to expand its operations into the global economy. In 1999, the firm merged with AlliedSignal Inc., opening the door for more international clientele.
Honeywell International Inc. (HON +0.78%)
Today, Honeywell plays a vital role across the aerospace, industrial automation, energy, and sustainability sectors. It currently has +300 gas detecting products that focus on 28 gases. This position has allowed the company to secure a $138.537B market cap with a 52-week trading Range of $189.75 – $242.77. Those seeking a reputable gas sensing manufacturer should do more research into HON.
Modified Graphene Sensors – Creating a Safer World
There has never been more demand for gas sensing technology. Across the globe, these systems help to keep factories running, pollution in check, and homes safe. This latest study could boost these capabilities further, ushering in an age of personal safety equipment and trackability that was previously impossible. For now, congrats to the research team on opening the door for future breakthroughs.
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Study Reference:
1. Iwakami, S., Yakushiji, S., & Ohba, T. (2025). Graphene functionalization by O₂, H₂, and Ar plasma treatments for improved NH₃ gas sensing. ACS Applied Materials & Interfaces, 17(1), 1992–1999. https://doi.org/10.1021/acsami.4c17257