Blog @ NanoVic - Nanotechnology Blog

Dye-sensitized solar cells are a type of solar cell which uses an organic dye to to absorb incoming photons and produce excited electrons. Have a look here for a nice diagram of one. Typically, these sorts of cells contain a transparent, conductive coating (typically an oxide such as titanium dioxide, on glass), acting as the anode. A separate coating, on the other plate, consists of platinum and acts as a catalytic conductor.

These types of coatings have their drawbacks though. The oxide films work best when they are spread on rigid, stable structures such as glass, limiting the types of structures that can be made. Platinum films are effective, but expensive to produce.

In order to tackle these problems researchers tried to replace both of the films with nanotubes. This meant finding a way to achieve the optimal parameters for transparency, conductivity and catalytic function. Ordinarily, carbon nanotubes are mid-range for these three properties. Researchers found that introducing defects into the tubes, by exposing them to ozone which adds extra chemical groups into the tube, they actually found a big increase in the catalytic function. A great example of how changes in the structures of nanomaterials can have such huge effects on their properties. The link to the research article can be found here.

The researchers are currently applying to patent this technology, which will hopefully mean cheaper, more flexible solar cells on their way to meet the demands of the ever increasing renewable energy market.

The Large Hadron Collider, or LHC, is due to fire up later this year. Dubbed ‘the biggest experiment ever’, it’s hoped the LHC will help answer the question of what the universe is made of, by recreating conditions similar to those a fraction of a second after the Big Bang, smashing particles together to generate up to 600 million collisions per second.

But will the LHC make it possible to make a black hole What about a black hole big enough to destroy the earth?!

(image from the LHC image library)

According to the information put out by CERN:

‘According to some theoretical models, tiny black holes could be produced in collisions at the LHC. They would then very quickly decay into what is known as Hawking radiation (the tinier the black hole, the faster it evaporate) which would be detected by experiments. Cosmic rays with very much more energy than that available a the LHC could also in principle produce black holes. However no evidence for such phenomena has so far been found.

You can read about physicistStephen Reucroft and John Swains thoughts on the possibility that the flick of the switch will end us all over at the Dr Knowledge Blog.

Meanwhile, the construction of the LHC is complete, and this site claims to countdown to the moment they flick the switch. I’m not sure how accurate that one is, but you can see the official programme for the cooling of the accelerator (requiring 96 tonnes of helium to cool down the LHC and fill it for first operation) here.

Researchers at Swansea University are developing a new, eco-friendly nanomaterial that they claim could generate as much electricity as 50 wind farms.

They are investigating ways of painting solar cells, which efficient at capturing low light radiation, onto the flexible steel surfaces commonly used for cladding buildings. This could then create buildings that could power themselves!!

Researchers are working closely with a company that produces around 100 million square meters of steel building cladding a year. If all this cladding was treated with the new solar cell material, it could be generating 4,500 gigawatts of electricity a year, the equivalent of 50 wind farms!

The ABC Science Show hosted by Robyn Williams is my favourite podcast for brisk strolls around the neighbourhood. This week the show has a nano focus, with topics as follows: 

• Green at work
• Quantum dots and nanowires
• Gene radar
• Nanotechnology in energy generation and use of resources
• Solar cells
• Regeneration of nerves
• New smart materials
• Surface chemistry
• Calcivirus delivers vaccines in humans

Can’t wait to have a listen!

Nanotechnology: The Power of Small, the first major television series to look at the implications of advances in nanotechnology, will begin airing on local US public broadcasting stations in April.

The series’ three programs explore critical questions about nanotechnology’s potential impact on privacy, the environment and human health: Will nanotechnology make you safer, or will it be used to track your every move? Will nanotechnology keep you young, and what happens if you live to be 150? Will nanotechnology help clean up the earth, or will it be the next asbestos?

The programme is funded by the National Science Foundation (NSF) and involves the host asking policymakers, scientists, journalists and community leaders to wrestle with difficult but essential issues about nanotechnology’s potential to impact people’s privacy and security, health and environment. Featured experts include Harvard University researcher George M. Whitesides, PEN chief scientist Andrew Maynard, and author Joel Garreau, among others.

To view the series click here

Eric Isaacs (Argonne National Laboratories, USA) got our brains ticking over at ICONN2008 with his presentation on the role of nanotechnology in energy creation. While we all know that solar energy is greatly underutilised, the problem is that currently its mode of collection is very inefficient - the best on record is 32% efficiency (at least 50% efficiency would be viable). In addition, solar energy is difficult to store. Using solar energy is therefore very expensive compared to more traditional sources of energy, such as petroleum. The Argonne National Laboratory is currently focussing on 3 main areas to improve the use of solar as an energy source:

1. photovoltaics (such as the use of nanobiohybrids for solar electric conversion);
2. solar fuel (exemplified by artificial photosynthesis);
3. solar thermal (by way of self-assembled nanoparticles).

Interestingly, Isaacs commented that unlike in the past, when companies like Bell Labs (where Isaacs was a past employee) were the primary drivers of socially-beneficial invention, these days the engine for fundamental innovation needs to come from a multi-tiered approach involving academia (ie government labs using tax-payers money), small business and medium-large scale industry. The challenge as I see it is to get all these groups aware of each other, and to work together to allow such collaborations to happen. Networking at conferences such as ICONN can only promote such opportunities. Entities such as Nanovic are also critical.

 In breaking news….I stand here at the ICONN2008 internet cafe filled with new knowledge and great excitement regarding recent developments in nanotechnology. One of the hottest topics at the conference so far is the use of nanotechnology for energy generation and storage. A presentation by Micheal Gratzel (Ecole Polytechnique Federal de Lausanne, Switzerland) this morning was particularly relevant. In solving the world’s energy crisis, Michael really got down to the main point in his statement that “nanotechnology is a powerful tool to get the right molecular architecture for power generation and storage”. What he means is that nanotechnology allows humans to design and create new structures to separate charge (ie separate photons from electrons) and store that energy potential in batteries. That’s what power is all about. It’s inspiring stuff. More soon!

It’s one of those everyday annoyances, finding yourself with a flat battery in any one of the gadgets we carry around constantly now.  I would love the option of charging your phone or your ipod while you’re out and about.  And it looks like that may be possible soon, with a recent report in Nature on power production from nanotextiles (watch me carefully avoid the use of the pun ‘power dressing’!)

 The textiles consist of zinc oxide nanowires which generate electricity by the piezoelectric effect, in other words, produce electricity when under mechanical stress.  The zinc oxide nanowires are embedded around a Kevlar fibre to produce something looking like a bottle-brush.   Some are then coated in a nanolayer of gold, to act as an electrode. These are aligned and the ‘bristles’ rub past each other, creating the electrical current (see picture).   Once optimised, this nanotextile should provide a simple and cheap way to convert energy of walking into electrical energy.  This report follows an earlier report of a knee brace designed to harvest energy from walking.    Maybe one day we will be able to throw our old chargers out and simply plug in and go for a stroll!

More awesome science videos, thanks to electromagnetism! Diamagnetism is a weak repelling force from an externally applied magnetic field. All materials are inherently diamagnetic. You and I are diamagnets. What happens when you put a diamagnet in a magnetic field? Well, not much. Diamagnetism is a very weak force (millions of times weaker than ferromagnetism). Unless that magnetic field is extremely strong, say 16 tesla (the earths magnetic field is approximately 50 micro tesla). Then cool things happen. Diamagnetic levitation! Behold flying frogs!

Lovers of carbon nanotubes as I know you all are, it’s time to move over and make way for boron……or so say Jun Ni and his research team in Beijing, China. Boron is the 5th element in the periodic table, having the chemical symbol B (carbon, C, is the 6th element). As would be expected from their divergent periodic groupings, boron nanotubes assemble with a different chemistry to those of carbon. Rather than forming the classic ‘chicken-wire’ pattern, boron atoms are naturally inclined to form a buckled triangular latticework. However, theoretical modelling by Ni and his colleagues has allowed them to predict that adding an extra atom to the centre of some hexagons in the unstable ‘carbon-like’ boron lattice would confer the nanostructure with enough stability to be used commercially. Boron nanotubes of differing diameters are predicted to have a range of possible applications, largely as a result of varied electrical properties; wide tubes should be metallic conductors and perhaps even superconductors at high temperatures. Narrow tubes would offer value in the form of semiconductors. The next step in the boron nanotube story is to find an effective catalyst for production by chemical vapour deposition. Personally, I find all this chemistry talk really exciting….hope none of you found this blog too boron-ing. [Image courtesy of New Scientist]