Hidden costs: Carbon nanofibres were chosen for one of the studies as they have attracted attention in recent years due to their exceptional electrical and mechanical properties.
Credit: Wikimedia
NEW YORK: The manufacture of nanomaterials may have significant environmental impacts, according to new research, which reveals that some require significantly more energy over their lives than conventional materials.
A nanomaterial is defined as a manufactured material that is less than 100 nanometres (one billionth of a metre) across in one of its dimensions. Nanomaterials are used in a wide range of consumer products including paint, batteries, automobiles, electronics, cosmetics, sunscreen and some food products.
Small size, big footprint
Some experts have argued that producing nanomaterials would require less energy and create less waste than the manufacture of conventional materials because a smaller amount of the nanomaterials are used to accomplish the same task as their conventional counterparts.
But several studies published in the current Journal of Industrial Ecology show that the environmental footprint of nanotechnology can far outweigh it's diminutive size.
One of the studies showed that, taking into account the energy and environmental impact over their entire life cycle, carbon nanofibres use up 13 to 50 times as much energy as aluminium, a commonly manufactured conventional material.
Carbon nanofibres were chosen as they have attracted much attention in recent years due to their exceptional electrical and mechanical properties, said Vikas Khanna lead author of the study at Ohio State University in Columbus, USA.
For example, they have a mechanical strength 10 times that of steel, an attractive feature for a number of industries.
Significant energy investment
The manufacturing of the nanofibres requires "significant energy investment," said Khanna.
The environmental footprint may vary greatly depending on the specific use of the nanomaterials though, he said – so the next step is comparing the energy required when using the materials for a similar job.
His team is now testing the relative impact of creating automobile body panelling made from carbon nanofibre polymers and more conventional steel.
First research of its kind
"Very little life cycle assessment has been done of nanotechnology and little attention has been paid to the environmental impacts of manufacturing of nanomaterials [before now]," said Reid Lifset, a scientist at Yale University in New Haven, U.S. and editor-in-chief of the Journal of Industrial Ecology.
According to Peter Binks, the chief executive officer of Nanotechnology Victoria, a nanotech lobbying body at Monash University in Melbourne, Australia, this is the first time that "very important" research of this nature, has been carried out.
Nanotechnology manufacture, is however at an early stage, commented Binks, and will no doubt be refined over time, in the same way that conventional manufacturing has. Comparison between "the first outputs of an emerging technology" and established products like aluminium may therefore be inappropriate, he said.
