Can Borophene Compete with Graphene?
Borophene is an innovative new 2D mono-atomic material that can rival Graphene in terms of strength and flexibility. It’s also cheaper to produce and is a better conductor
What is Graphene?
Not so long ago, Graphene was recognized as a prodigious material able to transform the world of technology with its various uses in electronics applications, including RAM (random-access memory), displays, printed Graphene for paper electronics, and automobile batteries.
It’s a super-strong, atom-thick sheet of carbon “chicken wire” that can be shaped into tubes, balls, and various shapes. As it conducts electricity, material scientists predicted a new era of graphene-based computer processing and a profitable graphene chip sector. The graphene industry was launched with a €1 billion investment by the European Union.
This brave new graphene-based world is still a long way off. The main drawback of this is that Graphene takes a long time to develop and costs more than other materials.
Other difficulties with Graphene include its mechanical rigidity, which makes it unsuitable for systems that require significant compression, stretching, or torsion tolerance. It has a bandgap that makes it unsuitable for simple on/off switching. Because of its oxidation susceptibility, it cannot be used as a catalyst in oxidizing environments. Furthermore, it may contain sharp edges that could tear cell membranes and cause them to malfunction.
As a result, it has sparked excitement about other two-dimensional materials. The most interesting of them is Borophene, which comprises a single layer of boron atoms that can create various crystallites.
What is Borophene?
Borophene does not have a long history. It is a relatively new compound. In the 1990s, scientists predicted its existence by running computer simulations to explain how boron atoms may form a monolayer. But it wasn’t until 2015 that this unique compound was created via chemical vapour deposition. In this process, a heated gas of boron atoms condenses over a cool surface of pure silver.
The systematic arrangement of silver atoms forces boron atoms into a similar pattern, with each atom forming a flat hexagonal shape by connecting to as many as six other atoms. However, a large number of boron atoms combine with only four or five other atoms, resulting in voids in the structure. The voids’ pattern in borophene crystals gives them their distinct features.
In scientific terms, Borophene is defined as a “proposed crystalline allotrope for boron” or a “crystalline atomic monolayer of boron”. The atoms’ hexagonal structure is highly similar to that of Graphene carbon atoms, except they are boron atoms with an extra boron atom in the centre of each hexagon.
Outstanding properties of Borophene
- It has record-high flexibility and higher stiffness to weight ratio than Graphene.
- It is an excellent conductor of electricity and heat, and it also superconducts.
- It can catalyse the decomposition of molecular hydrogen into hydrogen ions and water into hydrogen and oxygen ions.
- It is lightweight and fairly reactive, making it a promising candidate for storing metal ions in batteries.
- It can act as a reactant.
- It can store more than 15% of its weight in hydrogen due to its adsorption property and large surface area of atomic layers.
Why is Borophene Better Than Graphene?
Both materials are closely related as their atomic structures are quite similar. With several scientific factors and the above-mentioned characteristics of this material, Borophene is categorized as the best alternative that goes beyond the benefits and quality Graphene provides.
To start with, Borophene is stronger and more flexible, which is an important attribute when considering that Graphene is harder than diamond and is made entirely of carbon (one of the hardest elements that exist on the planet).
It is also a superconductor of electrical current. Its unique crystalline structure, formed by boron atoms, is responsible for this property, as the voids that remain between the atoms allow boron to be superconducting.
Then there is Borophene’s ability to catalyze the decomposition of hydrogen and oxygen is one of its many advantages. “Borophene has excellent catalytic effects in the hydrogen evolution reaction, the oxygen reduction reaction, the oxygen evolution reaction, and the CO2 electro-reduction reaction,” says Zhi-Qiang Wang’s research team at the University of Xiamen (China). This may shape the future of water-based power cycles.
Nonetheless, scientists must conduct intensive research before Borophene may be used extensively. For instance, they have yet to discover a means to produce large-scale Borophene. Because of the material’s reactivity, it is susceptible to oxidation and must be carefully protected.
Borophene, like Graphene, is difficult to handle and expensive to produce because of these two features. However, chemists have a lot of faith that Borophene has the potential to be the next great wonder material.
Applications of Borophene
Currently, there are plenty of applications due to Borophene’s unique features:
Borophene can be used to fabricate devices that can be deformed and then returned to their original shape. Because Borophene is conductive, it could be an excellent material for flexible electronic devices.
Borophene is a promising electrode material for lithium-ion and sodium-ion batteries because of its large storage capacity, which results in a high power density and electrochemical performance. According to a recent study, Borophene has the largest storage capacity of all the 2D materials studied.
Borophene is a catalyst used in hydrogen evolution, oxygen reduction, and carbon dioxide electrochemical reduction. The electrochemical reduction of carbon dioxide, in particular, provides significant potential for improving climate change activities.
Borophene has been proved to have a high hydrogen storage capacity due to the boron atom’s low mass. The molecular hydrogen binding energy to the boron sheet is higher than Graphene.
Borophene can be used in gas sensing applications for ethanol, carbon monoxide, phosgene, and formaldehyde due to its gas adsorption capabilities. It also has unique electronic structures and large surface-area-to-volume ratios that make it a perfect candidate for developing gas sensors.
Future Research With Borophene
When proper temperature and design changes are made, Borophene can be shaped in various forms, as in a scanning tunnelling microscope. Some are adjusted to be smooth, while others are corrugated, similar to the ridges on a record. This corrugated form of Borophene may outperform Graphene as an electrical conductor. Hersam’s team is conducting additional research on this, so more data should be accessible soon.
“The next fundamental challenge is to demonstrate a free-standing sheet of this material that opens up a lot of science and engineering possibilities”, Akinwande added.
“Boron reacts with nearly everything around it,” said Hermann Sachdey, an inorganic scientist at Kaiserslautern’s Technical University. However, the chemical nature of Borophene may make it easier to work with than other 2D sheet materials.
According to Akinwande, cooled Borophene could be a superconductor, a material that conducts electrical charge with zero resistance. However, another 2D material, aluminium, is on the horizon, and it has the potential to be more conductive than both Graphene and Borophene. Clearly, the world of nanomaterials is experiencing a period of rapid development.