Graphene Technology Research Articles

Smartphone-based electrochemical sensing of propyl gallate in food samples by employing NiFe-Oxide decorated flexible laser-induced graphene electrode

Flexible graphene electronics utilizing laser-induced graphene (LIG) technology offer an efficient, cost-effective, and mask-free approach to produce graphene in a single step. LIG can be directly patterned on polyimide films, impacting their surface properties, chemical composition, and electrical conductivity. However, the electrochemical performance of standalone LIG is limited. To address this, the study enhances LIG by synthesizing nickel-iron Prussian blue analogues through co-precipitation and calcination, forming porous NiFe-Oxide, which is subsequently deposited onto the LIG surface via a facile physical deposition method. The porous NiFe-Oxide@LIG electrode material demonstrates excellent electrochemical sensing capabilities due to its high conductivity, improved surface area, enhanced active sites, and superior electrocatalytic performance for detecting the antioxidant propyl gallate (PG). This porous NiFe-Oxide@LIG electrode material features a linear detection range (0.5–5 μM), low detection limit (0.01 μM), high sensitivity (17.12 μAμM−1cm−2), and strong selectivity for PG. Additionally, it offers high reproducibility and repeatability, evidenced by the low relative standard deviation values of 2.61 % and 1.96 %, respectively. The practicality of the proposed sensor was validated using food samples, integrated into a smartphone-based sensing device, achieving satisfactory recovery rates above 79.2 %. This smartphone-based sensor enables effective onsite food quality and safety monitoring.

Influence of defocusing of UV pulse laser radiation on LIG synthesis on Polyetheretherketone

Laser-induced graphene (LIG) technology, a technique for preparing three-dimensional porous graphene by laser direct writing on carbon precursors under ambient condition, has been widely used due to its low cost and high efficiency. However, there is still a lack of research on the influence of the defocusing on LIG synthesis. In this paper, LIG is prepared by UV laser on Polyetheretherketone (PEEK) film, and a finite element simulation of this process is established to infer the temperature field. The influence of the defocusing on the structure, morphology, specific surface area SSA, and electrical properties of PEEK-LIG is investigated while maintaining the same energy radiated per unit area. The results show that the defocusing changes the structure and morphology of PEEK-LIG by affecting the temperature field distribution in both the surface and thickness directions, which affects the properties of LIG, where the surface area ratio Sdr does not depend on the defocusing amount monotonically. As the UV laser nears the beam waist at the threshold of LIG formation, Sdr has its maximum value and improves its electrical conductivity.

One-Step Fabrication of Composite Hydrophobic Electrically Heated Graphene Surface

Ice accumulation poses considerable challenges in transportation, notably in the domain of general aviation. The present study combines the strengths and limitations of conventional aircraft deicing techniques with the emerging trend toward all-electric aircraft. This study aims to utilize laser-induced graphene (LIG) technology to create a multifunctional surface, seamlessly integrating hydrophobic properties with efficient electrical heating to mitigate surface icing effectively. We investigated the utilization of a 10.6 μm CO2 laser for direct writing on polyimide (PI), a widely used insulating encapsulation material. From the thermomechanical perspective, our initial analysis using COMSOL Multiphysics software (V5.6) revealed that when the laser power P exceeds 5 W, the PI substrate experiences ablative damage. The experimental results show that when P ≤ 5 W, an increase in power has a positive impact on the quality, surface porosity, roughness reduction, line-spacing reduction, and water contact-angle enhancement of the graphene. Conversely, when P > 5 W, higher power negatively affects both the substrate and the graphene structure by inducing excessive ablation. However, it influences the graphene line height positively and is consistent with overall experimental–simulation congruence. Furthermore, the incorporation of high-quality graphene resulted in a surface that exhibited higher contact angles (CA > 120°), lower energy consumption, and higher heating efficiency compared to the use of traditional electrically heated materials for anti-icing applications. The potential applications of this one-step fabrication method extend across various industries, particularly aviation, marine engineering, and other ice-prone domains. Moreover, the method has extensive prospects for addressing pivotal challenges associated with ice formation and serves as an innovative and efficient anti-icing technology.

Toward qualitative growth: Exaptations, graphene and Industry 4.0

AbstractThis contribution aims to address the intriguing issue of whether Industry 4.0, as a techno-economic paradigm shifter, may have a greater potential for exaptation (i.e., using it not for pursuing of quantitative but that of qualitative development) and, if so, what technologies may accelerate this process. Existing research indicates that graphene technology has the potential to lead the way in this area. The paper addresses not only why and how a graphene-aided Industry 4.0 can be conducive to this function (i.e., making exaptations easier on a larger scale), it examines the wider context for exaptations by questioning whether the current setup of the real economy, the financial universe, and the public sector offers a supportive environment for exaptations.

Multifunctional Laser-Induced Graphene-Based Microfluidic Chip for High-Performance Oocyte Cryopreservation with Low Concentration of Cryoprotectants.

Oocyte cryopreservation is essential in the field of assisted reproduction, but due to the large size and poor environmental tolerance of oocytes, cell freezing technology needs further improvement. Here, a Y-shaped microfluidic chip based on 3D graphene is ingeniously devised by combining laser-induced graphene (LIG) technology and fiber etching technology. The prepared LIG/PDMS microfluidic chip can effectively suppress ice crystal size and delay ice crystal freezing time by adjusting surface hydrophobicity. In addition, LIG endows the microfluidic chip with an outstanding photothermal effect, which allows to sharply increase its surface temperature from 25 to 71.8°C with 10s of low-power 808nm laser irradiation (0.4Wcm-2). Notably, the LIG/PDMS microfluidic chip not only replaces the traditional cryopreservation carriers, but also effectively reduces the dosage of cryoprotectants (CPAs) needed in mouse oocyte cryopreservation. Even when the concentration of CPAs is cut in half (final concentration of 7.5% ethylene glycol (EG) and 7.5% dimethyl sulfoxide (DMSO)), the survival rate of oocytes is still as high as 92.4%, significantly higher than the control group's 85.8%. Therefore, this work provides a novel design strategy to construct multifunctional microfluidic chips for high-performance oocytes cryopreservation.

Ethanol Solvation of Polymer Residues in Graphene Solution-Gated Field Effect Transistors.

The persistence of photoresist residues from microfabrication procedures causes significant obstacles in the technological advancement of graphene-based electronic devices. These residues induce undesired chemical doping effects, diminish carrier mobility, and deteriorate the signal-to-noise ratio, making them critical in certain contexts, including sensing and electrical recording applications. In graphene solution-gated field-effect transistors (gSGFETs), the presence of polymer contaminants makes it difficult to perform precise electrical measurements, introducing response variability and calibration challenges. Given the absence of viable short to midterm alternatives to polymer-intensive microfabrication techniques, a postpatterning treatment involving THF and ethanol solvents was evaluated, with ethanol being the most effective, environmentally sustainable, and safe method for residue removal. Employing a comprehensive analysis with XPS, AFM, and Raman spectroscopy, together with electrical characterization, we investigated the influence of residual polymers on graphene surface properties and transistor functionality. Ethanol treatment exhibited a pronounced enhancement in gSGFET performance, as evidenced by a shift in the charge neutrality point and reduced dispersion. This systematic cleaning methodology holds the potential to improve the reproducibility and precision in the manufacturing of graphene devices. Particularly, by using ethanol for residue removal, we align our methodology with the principles of green chemistry, minimizing environmental impact while advancing diverse graphene technology applications.

Chemiresistors Based on Hybrid Nanostructures Obtained from Graphene and Conducting Polymers with Potential Use in Breath Methane Detection Associated with Irritable Bowel Syndrome.

This paper describes the process of producing chemiresistors based on hybrid nanostructures obtained from graphene and conducting polymers. The technology of graphene presumed the following: dispersion and support stabilization based on the chemical vapor deposition technique; transfer of the graphene to the substrate by spin-coating of polymethyl methacrylate; and thermal treatment and electrochemical delamination. For the process at T = 950 °C, a better settlement of the grains was noticed, with the formation of layers predominantly characterized by peaks and not by depressions. The technology for obtaining hybrid nanostructures from graphene and conducting polymers was drop-casting, with solutions of Poly(3-hexylthiophene (P3HT) and Poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-bithiophene] (F8T2). In the case of F8T2, compared to P3HT, a 10 times larger dimension of grain size and about 7 times larger distances between the peak clusters were noticed. To generate chemiresistors from graphene-polymer structures, an ink-jet printer was used, and the metallization was made with commercial copper ink for printed electronics, leading to a structure of a resistor with an active surface of about 1 cm2. Experimental calibration curves were plotted for both sensing structures, for a domain of CH4 of up to 1000 ppm concentration in air. A linearity of the curve for the low concentration of CH4 was noticed for the graphene structure with F8T2, presenting a sensitivity of about 6 times higher compared with the graphene structure with P3HT, which makes the sensing structure of graphene with F8T2 more feasible and reliable for the medical application of irritable bowel syndrome evaluation.

Structure-Foldable and Performance-Tailorable PI Paper-Based Triboelectric Nanogenerators Processed and Controlled by Laser-Induced Graphene.

Laser-induced graphene (LIG) technology has provided a new manufacturing strategy for the rapid and scalable assembling of triboelectric nanogenerators (TENG). However, current LIG-based TENG commonly rely on polymer films, e.g., polyimide (PI) as both friction material and carbon precursor of electrodes, which limit the structural diversity and performance escalation due to its incapability of folding and creasing. Using specialized PI paper composed of randomly distributed PI fibers to substantially enhance its foldability, this work creates a new type of TENG, which are structurally foldable and stackable, and performance tailorable. First, by systematically investigating the laser power-regulated performance of single-unit TENG, the open-circuit voltage can be effectively improved. By further exploiting the folding process, multiple TENG units can be assembled together to form multi-layered structures to continuously expand the open-circuit voltage from 5.3 to 34.4Vcm-2, as the increase of friction units from 1 to 16. Last, by fully utilizing the unique structure and performance, representative energy-harvesting and smart-sensing applications are demonstrated, including a smart shoe to recognize running motions and power LEDs, a smart leaf to power a thermometer by wind, a matrix sensor to recognize writing trajectories, as well as a smart glove to recognize different objects.

Laser-Induced Graphene-Based Sensors in Health Monitoring: Progress, Sensing Mechanisms, and Applications.

The rising global population and improved living standards have led to an alarming increase in non-communicable diseases, notably cardiovascular and chronic respiratory diseases, posing a severe threat to human health. Wearable sensing devices, utilizing micro-sensing technology for real-time monitoring, have emerged as promising tools for disease prevention. Among various sensing platforms, graphene-based sensors have shown exceptional performance in the field of micro-sensing. Laser-induced graphene (LIG) technology, a cost-effective and facile method for graphene preparation, has gained particular attention. By converting polymer films directly into patterned graphene materials at ambient temperature and pressure, LIG offers a convenient and environmentally friendly alternative to traditional methods, opening up innovative possibilities for electronic device fabrication. Integrating LIG-based sensors into health monitoring systems holds the potential to revolutionize health management. To commemorate the tenth anniversary of the discovery of LIG, this work provides a comprehensive overview of LIG's evolution and the progress of LIG-based sensors. Delving into the diverse sensing mechanisms of LIG-based sensors, recent research advances in the domain of health monitoring are explored. Furthermore, the opportunities and challenges associated with LIG-based sensors in health monitoring are briefly discussed.

An Overview of the Electronic Structure of Monolayer Graphene

Monolayer graphene is a nanostructured material that consists of layers of graphene, each layer of single-layer graphene consists of a layer of carbon atoms that are interconnected in a hexagonal lattice. The crystal structure of monolayer graphene is two dimensional and carbon atoms are inserted in a hexagonal lattice. The band structure of monolayer graphene includes two main bands that located at points K and K’ considered as quantum bands of electrons and holes. The electronic properties of monolayer graphene include the movement of electrons at very high speed and maintaining their spin. Also, monolayer graphene has unique optical properties and can be used as an optical switcher in electronic devices. Which from the basis of the contemporary technology of graphene and is progressing, therefor, research in this field is important and this research was carried out in a library method and its purpose is to investigate the electronic structure of single – layer graphene.

Flash healing of laser-induced graphene

The advancement of laser-induced graphene (LIG) technology has streamlined the fabrications of flexible graphene devices. However, the ultrafast kinetics triggered by laser irradiation generates intrinsic amorphous characteristics, leading to high resistivity and compromised performance in electronic devices. Healing graphene defects in specific patterns is technologically challenging by conventional methods. Herein, we report the rapid rectification of LIG’s topological defects by flash Joule heating in milliseconds (referred to as F-LIG), whilst preserving its overall structure and porosity. The F-LIG exhibits a decreased ID/IG ratio from 0.84 – 0.33 and increased crystalline domain from Raman analysis, coupled with a 5-fold surge in conductivity. Pair distribution function and atomic-resolution imaging delineate a broader-range order of F-LIG with a shorter C-C bond of 1.425 Å. The improved crystallinity and conductivity of F-LIG with excellent flexibility enables its utilization in high-performance soft electronics and low-voltage disinfections. Notably, our F-LIG/polydimethylsiloxane strain sensor exhibits a gauge factor of 129.3 within 10% strain, which outperforms pristine LIG by 800%, showcasing significant potential for human-machine interfaces.

Studying the Effectiveness of Shaped Charge Jets Created by Graphene-containing Shaped Charge Liners

The paper presents selected results of studies conducted within the framework of the following research project: “Use of graphene and new multilayer explosive technologies in materials for shaped charge liners" (The National Centre for Research and Development in Poland: project No: DOB-BI08/03/01/2016). This study was performed by a consortium made up of the following entities: Institute of Precision Mechanics, Military University of Technology and the Mototechnika company (Poland). The main objective of the performed experiments was to test the effectiveness of shaped charge liners produced with the use of powder metallurgy methods, from mixtures containing copper powder and graphene-coated copper powder. The content of the latter equaled 0%, 1%, 5% and 10%, respectively. Shaped charge jets created with the use of liners made from the powder mixtures tested were recorded with the help of X-ray technology. Firing tests were conducted against steel barriers and the depth of penetration was determined. The obtained results showed that the addition of graphene powder to pure copper powder practically does not increase the depth of penetration of the shaped charge jet compared to scenarios in which sintered liners without this additive were used.

Automatically Aligned and Environment-Friendly Twisted Stacking Terahertz Chiral Metasurface with Giant Circular Dichroism for Rapid Biosensing.

Chiral metasurfaces are capable of generating a huge superchiral field, which has great potential in optoelectronics and biosensing. However, the conventional fabrication process suffers greatly from time consumption, high cost, and difficult multilayer alignment, which hinder its commercial application. Herein, we propose a twisted stacking carbon-based terahertz (THz) chiral metasurface (TCM) based on laser-induced graphene (LIG) technology. By repeating a two-step process of sticking a polyimide film, followed by laser direct writing, the two layers of the TCM are aligned automatically in the fabrication. Laser manufacturing also brings such high processing speed that a TCM with a size of 15 × 15 mm can be prepared in 60 s. In addition, due to the greater dissipation of LIG than that of metals in the THz band, a giant circular dichroism (CD) of +99.5 to -99.6% is experimentally realized. The THz biosensing of bovine serum albumin enhanced by the proposed TCMs is then demonstrated. A wide sensing range (0.5-50 mg mL-1) and a good sensitivity [ΔCD: 2.09% (mg mL-1)-1, Δf: 0.0034 THz (mg mL-1)-1] are proved. This LIG-based TCM provides an environment-friendly platform for chiral research and has great application potential in rapid and low-cost commercial biosensing.

Graphene Devices for Aerial Wireless Communications at THz

This paper investigates the state-of-the-art of graphene-based technologies for the prospective use cases of end-to-end terahertz (THz) communication systems, such as industrial Internet of Things (IoT) applications and unmanned aerial vehicles (UAVs). THz communications offer ultra-high throughput and enhanced sensing capabilities, enabling advanced applications like UAV swarms and integrated sensing, localization, and mapping. The potential of wireless THz communication can be unlocked by graphene technology. Graphene, owing to its remarkable electrical, thermal, and mechanical properties, emerges as a promising candidate for a multitude of applications in aerial wireless communications in the THz band, including high-speed electronic devices, tunable metamaterials, and innovative antennas. However, reliable tools for the simulation-based design of graphene components, able to account for the fabrication-related uncertainties, are still missing. This paper presents the envisaged possibilities of wireless communications in THz bands, overviews graphene devices for RF applications at THz, and discusses the open issues of modelling THz devices and THz channel.

A patterning technology of transfer-free graphene for transparent electrodes of near-ultraviolet light-emitting diodes

A technology for the fabrication of transfer-free, patterned graphene on semiconductor or weakly catalytic metal substrate is presented, and the graphene transparent electrodes on GaN-based LED with 398 nm wavelength is fabricated accordingly.

Exaptationary Industry 4.0: Graphene as pathfinder?

This paper seeks to answer the puzzling question whether Industry 4.0 inevitably triggers a sociogenesis that results in new attitudes toward the nature of the socio-economic innovation ecosystem. It asks whether Industry 4.0, as a shifter of techno-economic paradigm, may carry higher exaptation potential, and if so, which technology could catalyse this effect. Prevailing literature suggests that graphene technology can easily become a pathfinder in this respect. The paper does not only consider why and how a graphene-based unfolding of Industry 4.0 can fulfil this function (i.e., making exaptations easier in a broader scale), but it also takes into account the wider context for exaptations by asking whether the current configuration of the real economy, the financial universe and the public sector offers a supportive ground for innovation and exaptation seeker behaviours.

Somatosensory Electro-Thermal Actuator through the Laser-Induced Graphene Technology.

The biological system realizes the unity of action and perception through the muscle tissue and nervous system. Correspondingly, artificial soft actuators realize the unity of sensing and actuating functions in a single functional material, which will have tremendous potential for developing intelligent and bionic soft robotics. This paper reports the design of a laser-induced graphene (LIG)electrothermal actuator with self-sensing capability. LIG, a functional material formed by a one-step direct-write lasing procedure under ambient air, is used as electrothermal conversion materials and piezoresistive sensing materials. By transferring LIG to a flexible silicone substrate, the design ability of the LIG-based actuator unit is enriched, along with an effectively improved sensing sensitivity. Through the integration of different types of well-designed LIG-based actuator units, the transformations from multidimensional precursors to 2D and 3D structures are realized. According to the piezoresistive effect of the LIG units during the deformation process, the visual synchronous deformation state feedback of the LIG-based actuator is proposed. The multimodal crawling soft robotics and the switchable electromagnetic shielding cloak serve as the demonstrations of the self-sensing LIG-based actuator, showing the advantage of the design in remote control of the soft robot without relying on the assistance of visual devices.

A Laser-Induced Graphene-Based Sensor Modified with CeO2 for Determination of Organophosphorus Pesticides with Improved Performance

In this work, a flexible electrochemical sensor was developed for the detection of organophosphorus pesticides (OPs). To fabricate the sensor, graphene was generated in situ by laser-induced graphene (LIG) technology on a flexible substrate of polyimide (PI) film to form a three-electrode array, and pralidoxime (PAM) chloride was used as the probe molecule. CeO2 was used to modify the working electrode to improve the sensitivity of the sensor because of its electrocatalytic effect on the oxidation of PAM, and the Ag/AgCl reference electrode was prepared by the drop coating method. The effects of the laser power, laser scanning speed, and CeO2 modification on the electrochemical properties of the sensor were studied in detail. The results prove that the sensor has good repeatability, stability, and anti-interference ability, and it shows an excellent linear response in the chlorpyrifos concentration range from 1.4 × 10−8 M to 1.12 × 10−7 M with the detection limit of 7.01 × 10−10 M.

Application of Graphene Technology in the Removal of Heavy Metal Ions in Wastewater

Nowadays, heavy metal pollution has become a serious problem. Toxic heavy metal ions can result in extreme damage to the environment and human society. Under that situation, methods that can remove the heavy metal ions in water have been required. Graphene technology can be widely applied to the removal of heavy metal ions. This article will explain the preparation of graphene oxide and reduced graphene oxide and the efficiency and influence factors of the method applied in water treatment. The method can remove many kinds of mainly occurring toxic heavy metal ions with very high efficiency. Also, large-scale production of graphene oxide can be achieved. The removal of heavy metal ions in water by graphene technology can be a practical method in the water treatment field.

Spinal Cord Injury Repair Using Flash Graphene Based Treatments: A Literature Review

Introduction: Spinal cord injury is a prominent neurological complication and is characterized by motor, sensory and autonomic dysfunction. It can cause paralysis depending on the area that is affected within the spinal cord. There have been many attempts to mitigate this condition and regeneration of neurons is one of the leading cures. Graphene is a carbon compound that is made from graphite. This unique one-atom layer is a versatile substance with potential uses in electronics due to its flexibility, conductance properties, and transparency. In the past, the creation of graphene was very expensive but now with the new technology of flash graphene, a method where carbon compounds are zapped into graphene flakes through flash heating, graphene is an accessible material for scaffolds to renew neurogenesis within spinal cord injury patients. Methods: A literature search was conducted using predetermined inclusion criteria and resulted in multiple primary research papers that presented research on graphene as a potential scaffolding agent for spinal cord injury. Results: Graphene based interfaces used within spinal cord injury have shown an increase in cell viability and neuron regeneration. These graphene interfaces do not create a disturbance in the electrical conductances that occur within the neuronal network. Graphene woven technology can also detect subtle muscle, which allows for quantifiable regeneration data. Discussion: With the creation of graphene, the carbon becomes fixed in a solid state and can be used as a conductor within electronics. Graphene usage within the body is not considered toxic as long as it is used within measured concentrations. This technology can be used to significantly impact how patients with spinal cord injury recover, potentially regaining use of their previously paralyzed limbs through neuron regeneration on graphene interfaces such as scaffolds or nanoplatelets.