Invented by Maher F. El-Kady, Nahla Mohamed, Jack KAVANAUGH, Richard B. Kaner, Nanotech Energy Inc, University of California
One of the key drivers of the market for conductive graphene inks is the growing demand for flexible and wearable electronics. Graphene inks can be used to print conductive patterns on flexible substrates, such as textiles, which can then be integrated into wearable devices. These devices can be used for a variety of applications, including health monitoring, fitness tracking, and communication. Graphene inks can also be used to print conductive patterns on flexible displays, which can be used in a variety of applications, including smartphones, tablets, and e-readers.
Another driver of the market for conductive graphene inks is the growing demand for sensors. Graphene inks can be used to print conductive patterns on a variety of substrates, including paper and plastic, which can then be used to create sensors. These sensors can be used for a variety of applications, including environmental monitoring, food safety, and medical diagnostics. Graphene inks can also be used to create flexible and transparent electrodes, which can be used in touch screens and other electronic devices.
The market for conductive graphene inks is also being driven by the demand for energy storage devices. Graphene inks can be used to create electrodes for batteries and supercapacitors, which can be used to store energy. These devices can be used in a variety of applications, including electric vehicles, renewable energy systems, and portable electronics. Graphene inks can also be used to create flexible and transparent electrodes for solar cells, which can be used to generate electricity.
In terms of methods for producing conductive graphene inks, there are several different approaches. One approach is to use chemical reduction methods to reduce graphene oxide to graphene. Another approach is to use mechanical exfoliation methods to produce graphene flakes, which can then be dispersed in a solvent to create an ink. There are also several companies that are developing proprietary methods for producing conductive graphene inks.
In conclusion, the market for methods for and applications of conductive graphene inks is growing rapidly, driven by the demand for flexible and wearable electronics, sensors, and energy storage devices. There are several different methods for producing conductive graphene inks, and there are many companies that are developing proprietary methods. As the market for conductive graphene inks continues to grow, we can expect to see new applications and innovations in this field.
The Nanotech Energy Inc, University of California invention works as follows
The present disclosure discloses an exemplary energy-storage device and a method of making it, which comprises an exemplary conductive Graphene ink applied to exemplary substrates, resulting in durable, flexible and easy graphene films, as well as energy storage devices that can be used with and within various electronic devices and electronics.
Background for Methods for and applications of conductive graphene Inks
The development of high performance electrical energy storage devices is gaining significant attention as a result the rapidly increasing energy needs in modern life. Energy storage devices are used with and in a variety electronic devices and electronics. These devices can be made flexible to increase durability. The future growth of the technology is dependent on improving energy storage methods and materials, as well as developing devices and methods that better integrate technology into the various products.
The present disclosure is a solution for the increasing demand for high-performance electrical energy storage devices. Graphene materials, compositions, fabrication processes and devices with improved performances are described here. The subject matter described in this document provides high power density with excellent low temperature performance. This includes, but is not limited to applications for inkjet, screen, printed circuit board, RFID chips, smart fabric, conductive coatings and gravure, flexographic, printing. These applications provide improvements in electronics and energy storage with high storage capability, flexibility, as well as a high cycling ability. Supercapacitors and other energy-storage devices have low power and energy densities, as well as low cycling and capacitive abilities. Moore’s Law has seen rapid advances in electronic devices, but electrical energy storage devices are only a little more advanced due to the lack of materials with high charge storage capacities.
A conductive graphene-based ink is provided as a first aspect of the invention. It comprises: a solution of a binder, a first solvent and reduced graphene dioxide; a dispersion of reduced graphene and a second or third solvent; an additive conductive; a surfactant and defoamer.
In some embodiments, water and organic solvent can be used as at least one first solvent, second solvent and third solvent. Optionally, in some embodiments, the organic solvent comprises ethanol, isopropyl alcohol, N-methyl-2-pyrrolidone, cyclohexanone, terpineol, 3-methoxy-3-methyl-1-butanol, 4-hydroxyl-4-methyl-pentan-2-one, methyl isobutyl ketone, or any combination thereof.
In In In In In In In
In some embodiments the binder solution may include a binder in combination with a first liquid. In some embodiments the binder can be a polymer. In some embodiments, a polymer can be used as an alternative. In some embodiments, a synthetic polymer can be carboxymethyl-cellulose, polyvinylidenefluoride, polyvinyl alcohol, polyvinylpyrrolidone, poly(ethylene oxide), or ethyl-cellulose. In some embodiments, a dispersant can be used as a binder. In some embodiments the binder can be carboxymethylcellulose, polyvinylidenefluoride, polyvinyl alcohol, polyvinylpyrrolidone, poly(ethylene oxide), or ethylcellulose.
In In In In In In In In
Optionally, in certain embodiments, the concentration of the binder is between 0.5% and 2%. In some embodiments a concentration is optionally at least 0.5%. Optionally, the concentration of the binder is no more than 2% in certain embodiments. In some embodiments a binder solution concentration can range from 0.5% up to 0.625%. This includes 0.5% up to 0.875%. Other concentrations include 0.5% up to 0.625% In some embodiments, the concentration of the binding solution can be about 0.5%. This includes 0.625% to about 0.875%. It also includes 0.5% to about 1.25%. In some embodiments, the concentration of the binder is about 0.5%. In some embodiments, the concentration of the binder is not more than 0.5%.
In some embodiments, reduced graphene dioxide (RGO), and a second solvant can be used to make the dispersion.
In some embodiments the percentage of RGO dispersion by mass in the conductive ink can range from 0.25% up to about 1%. In some embodiments, the percentage by mass for the RGO in the conductive ink can be as low as 0.25%. In some embodiments, the percentage by mass for the RGO in the conductive ink can be as high as 1%. In some embodiments, the percentage by mass of RGO dispersion is 0.25% – 0.375%. This includes 0.25% – 0.5%. In some embodiments, the percentage by mass of RGO dispersion is about 0.25% to about 0.375%. It can also be about 0.5% to about 0.625%. In some embodiments, the percentage by mass of RGO dispersion is about 0.25%. In some embodiments, the percentage of RGO dispersion by mass in the conductive ink can be as low as 0.25% or less.
Option In In In In In In
In In In In In In In
In some embodiments the conductive material can be a carbon-based substance. In some embodiments the carbon-based additive can be a paracrystalline material. Paracrystalline carbon can be used in certain embodiments as an alternative to carbon black.
In some embodiments, silver can be used as a conductive additive. In some embodiments the silver can be silver nanoparticles or silver nanorods and nanowires. It may also include silver nanoflowers.
In In In In In In In
Some embodiments also comprise a nonionic surfactant.” In some embodiments the surfactant can be an acid or a nonionic one, or a combination of both. In some embodiments, an acid can be perfluorooctanoic, perfluorohexane, perfluorononanoic, or perfluorodecanoic. In some embodiments, a nonionic surfactant can be a polyethylene octylphenyl ether. Other nonionic options include a triton X 100, a nonoxynol-9 polyethylene octylphenyl ether or a polyethylene octylphenyl ether.
In some embodiments, the addition of large quantities of water to water-based graphene inks can increase the ink’s surface tension. In certain applications, like inkjet printing for example, it is necessary to have a controlled, low surface tension in order to maintain consistent jetting. In some embodiments, adding a surfactant can reduce the surface tension. This is because, as the units of the surfactant move towards the interface between water and air, the relative force of attraction of the non-polar heads weakens.
In In In In In In In
Some embodiments also comprise a defoamer. The defoamer may include an insoluble oil or silicone, a glycol or stearate and an organic solvent. Surfynol DF-1100 is another option, as well as alkyl polyacrylate. In some embodiments, an insoluble oil can be mineral oil, vegetable oils, white oils, or any combination of these. Optionally, in some embodiments, the silicone comprises polydimethylsiloxane, silicone glycol, a fluorosilicone, or any combination thereof. In some embodiments, polyethylene glycol can be used instead of ethylene glycol or propylene glycol. In some embodiments, glycol stearate or stearin can be used as the stearate. Optionally, in some embodiments, the organic solvent comprises ethanol, isopropyl alcohol, N-methyl-2-pyrrolidone, cyclohexanone, terpineol, 3-methoxy-3-methyl-1-butanol, 4-hydroxyl-4-methyl-pentan-2-one, methyl isobutyl ketone, or any combination thereof.
In In In In In In In
In some embodiments the solid matter by mass in the conductive graphene is between 2.5% and 10.5%. In some embodiments the solid matter by mass of conductive graphene is not less than 2.5%. In some embodiments, it is possible to have a solid matter content of up to 10.5% by mass. In some embodiments, solid matter content of the conductive ink by mass is between 2.5% and about 3.5%. This includes 2.5% up to approximately 4.5%; 2.5% up to approximately 5.5%; 2.5% up to approximately 6.5%; 2.5% upwards to roughly 8.5% or 2.5% upwards to roughly 9.5%. In some embodiments, solid matter content of the conductive ink by mass is between 2.5% and 3.5%. In some embodiments, it is possible to have a solid matter by mass content of the conductive ink that is no more than 2.5% or 3.5%. In some embodiments, it is possible to limit the solid matter by mass of conductive graphene-ink to no more than 2.5%.
Click here to view the patent on Google Patents.
Leave a Reply