NatureVolve

Q & A - Prabhuraj PhD

-

Please share some of the key environmen­tal problems faced by using traditiona­l energy devices, such as batteries.

Technicall­y, batteries and supercapac­itors cannot provide uninterrup­ted power, as they need charging. Regarding the environmen­tal side, these pose serious disposal issues, where those toxic and corrosive materials (cadmium, lead, mercury and lithium) can be easily absorbed onto soil, water etc. and create health complicati­ons in the surroundin­g areas.

These concerns demand an energy device with high running times and less environmen­tal issues.

Fuel cells, which offer higher energy specific energy than batteries, are perceived as a promising source of the future as they convert the chemical energy of fuel directly into electrical energy by a simple oxidationr­eduction reaction.

The electroche­mical mechanism results in the release of heat, water, electricit­y and other side products. In addition, they can continuous­ly supply electrical energy as long as the fuel and oxidant are supplied; hence operate for a long period of time and do not require charging as in the case of batteries, therefore saving time.

The energy conversion process takes place in a single step (chemical to electrical by oxidation/ reduction); and therefore gives higher efficiency (40% to 60%) than any other device.

Whereas, in combustion engines, reactions take place in two stages: combustion to mechanical, and then mechanical to electrical - resulting in lower efficiency (10% to 20%).

“Fuel cells are perceived as a promising source of the future.. they do not require charging as in the case of batteries.”

“Aside from research.. I believe sports activity can boost creative thinking..”

Overall, from an environmen­tally friendly perspectiv­e, the ability to deliver energy with high efficiency while using easily accessible fuels, fuel cells stand as a promising candidate for future energy requiremen­ts. In your 2017 TEDx Talk, graphene is described as “a wonder material for energy delivery and sustainabi­lity.” Why is the structure of graphene so effective compared to other materials, and what is its significan­ce for sustainabl­e energy?

Graphene is a newly discovered material (year 2004) in the family of carbon materials and is a single layer of graphite where carbon atoms are arranged in a hexagonal lattice, with carbon to carbon bond lengths of about 0.142 nm (nanometers) and thicknesse­s of around 0.3 nm (one atom thick).

This is the first two dimensiona­l material ever reported and henceforth considered as the basic structural element of all other carbon allotropes which include diamond, carbon nanotubes and more.

Before this discovery, two dimensiona­l crystals were theoretica­lly predicted not to exist as they were thought to be unstable. However, after confirming graphene’s existence, this led to an explosion of interest mainly attributed to its properties. The conductivi­ty of graphene is about 2000 S per cm, whereas that of copper is 0.5 S per cm.

This 4000-times increase is caused by both a loss of electron-mass while traveling through the structure, and the connectivi­ty of each carbon to three other carbon atoms. Technicall­y, this results in electron flow above and below the lattice. In addition, the high stability of 130 G Pa (higher than that of steel - 0.4 M Pa) is due to tight packing of carbon atoms.

Therefore, the 2D structure of graphene offers tremendous properties and gets a level of attention that is not observed for other 3D materials. How have you utilized graphene to produce an environmen­tally friendly fuel cell?

In simple terms, the engine room of a fuel cell comprises of two main components: electrode and membrane. The electrode component aids the electron transfer process, whereas the membrane aids the transfer of protons, both contributi­ng towards power output.

For an enhanced power output, these electrode and membrane components should be comprised of materials possessing high electron and proton conducting features, in addition to high stability characteri­stics.

Graphene is well known for these better physiochem­ical properties than any other materials.

 ??  ?? Below: Dr. Prabhuraj giving a TEDx talk in Durham, UK - 2017. © Prabhuraj PhD. All rights reserved.
Below: Dr. Prabhuraj giving a TEDx talk in Durham, UK - 2017. © Prabhuraj PhD. All rights reserved.
 ??  ?? Above: Dr. Prabhuraj pursuing golf when not working, to relax and harness creative thinking.
© Prabhuraj PhD. All rights reserved.
Above: Dr. Prabhuraj pursuing golf when not working, to relax and harness creative thinking. © Prabhuraj PhD. All rights reserved.

Newspapers in English

Newspapers from UK