Conductive ink is the first part of all printed digital units and circuit boards, creating the essential construction for built-in low-resistance circuits and speak to electrodes. Nevertheless, manufacturing a graphene-based conductive ink with good conductance and distribution stability in water stays a big problem.
Research: Facile Synthesis of Ag/Carbon Quantum Dots/Graphene Composites for Extremely Conductive Water-Primarily based Inks. Picture Credit score: wacomka/Shutterstock.com
A latest research revealed within the journal ACS Utilized Supplies & Interfaces focuses on the manufacturing of a remarkably conductive silver/carbon quantum dots/graphene (Ag/CQD/G) nanocomposite for manufacturing water-based conductive ink.
What’s a Conductive Ink?
Conductive ink is important within the manufacturing of stretchable digital gear. A high-performance conductive ink should have distinctive conductance, adherence to the substrate, and sturdiness. Relying on the substance utilized in its manufacturing, the conductive ink may be both metal-based or carbon-based.
Silver nanoparticles are presently probably the most also used supplies for producing conductive ink due to their nice electrical conductance and robust antioxidant traits. Silver supplies, nonetheless, are extremely pricey, and silver diffusion is a extreme downside that critically impacts the dependability of silver tracks.
Copper-based conductive ink is more cost effective and less complicated to supply than silver-based conductive ink. Nevertheless, it oxidizes readily, proscribing its industrial applicability.
Conductive ink, made up of carbon-based nanostructures resembling graphene, carbon nanotubes, carbon nanofibers, and carbon black, can remedy the challenges listed above and has attracted a lot curiosity as a consequence of its wonderful mechanical and electrical traits.
Graphene-Primarily based Conductive Ink: Purposes and Limitations
Graphene is a extremely promising carbon nanostructure for manufacturing conductive ink with conductance equal to silver ink. Moreover, graphene-based conductive ink gives a number of advantages, together with low cost value, excessive stability, and broad software.
Consequently, the creation of high-performance graphene-based ink can help in advancing printed microelectronics.
Water-soluble graphene oxide (GO) is commonly employed as a uncooked ingredient for manufacturing graphene-based conductive ink as a consequence of its cheap value and robust water degradability. Nevertheless, changing pre-printed GO patterns to conducting patterns includes excessive temperatures and highly effective decreasing chemical compounds, proscribing their use in wearable digital units.
Graphene nanosheets with pristine properties have higher electrical traits than rGO. Nevertheless, they have a tendency to agglomerate as a consequence of pi-pi stacking and van der Waals contacts, making them difficult to make use of in most solvents.
Enhancing Conductivity of Graphene-Primarily based Inks
From a cost-effective and ecological standpoint, it’s crucial to supply graphene-based nanomaterials with excessive conductance and robust dispersibility in water which are cost-effective, non-toxic, and sturdy below regular circumstances.
Totally different brokers and hydrophilic supplies, resembling polyvinyl pyrrolidone and polyethyleneimine ethoxylated, have been noticed to extend graphene solubility and sturdiness in water-based solvents. Nevertheless, these dispersion chemical compounds are troublesome to take away completely, leading to poor conductance composites and environmental contamination.
Carbon quantum dots (CQDs), that are amphiphilic semiconductors, may be deposited on the floor of graphene and dramatically enhance its conductance and solubility in water.
One other possible technique for growing the conductance of graphene-based conductive ink is to coat it with metallic nanoparticles (NPs). Many silver (Ag) nanoparticles with varied morphologies function as nanoscale connections between graphene sheets, leading to Ag/graphene composites with low contact resistance and elevated functionality for manufacturing a extremely conductive ink.
Highlights and Key Developments of the Research
On this research, the researchers created a singular Ag/CQDs/G composite by in-situ photo-reduction of silver nitrate and layering silver onto graphene nanosheets to supply a extremely conductive ink.
It is a easy and uncomplicated technique for getting ready Ag/CQDs/G composites, eliminating the want to scale back chemical compounds or high-temperature discount procedures.
The as-prepared Ag/CQDs/G nanocomposite demonstrated excessive dispersibility and sturdiness in water for 30 days. The introduction of Ag NPs to the Ag/CQDs/G nanocomposite resulted in a 97.2 p.c drop in electrical resistance in comparison with easy graphene sheets. As well as, the produced Ag/ CQDs/G patterns had a low contact resistivity following rolling compression.
The as-prepared nanocomposite is an acceptable filler for producing water-based conductive ink due to its sturdy water dispersibility and excessive electrical conductance. Moreover, after 5000 bending cycles, the printed patterns demonstrated distinctive structural stability, paving the way in which for producing a variety of high-performance adaptable digital merchandise, resembling circuit boards and radio-frequency identification units (RFIDs).
Gao, C. et al. (2022). Facile Synthesis of Ag/Carbon Quantum Dots/Graphene Composites for Extremely Conductive Water-Primarily based Inks. ACS Utilized Supplies & Interfaces. Obtainable at: https://pubs.acs.org/doi/10.1021/acsami.2c06298