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A 23 year old PhD student who developed cutting-edge photovoltaic (solar) technology using a low-cost inkjet printing process has won the British Council Eureka Prize for Young Leaders in Environmental Issues and Climate Change.

"Two billion people around the world have no access to reliable electricity. Imagine if this could be provided with energy that was both cheap and green." This thought motivated prize winner Nicole Kuepper's iJET research.

Current production techniques for photovoltaic cells makes them expensive and out of reach for most people in developing countries. The iJET solar cell represents a breakthrough: a simple, affordable solar device that can be made without high-tech environments or high cost inputs. Using Inkjet printing, aluminium spray and a low temperature pizza oven, Kuepper created the metal contacts necessary for a solar cell to generate electricity.

"Nicole's iJET solar cell will potentially bring affordable electricity to the poorest people in the world. But, more than this, it will be clean and renewable energy," says Australian Museum Director, Frank Howarth.

While photovoltaics is the world's most rapidly growing energy source, the production of solar cells currently requires sophisticated and expensive manufacturing facilities and highly trained personnel. These conditions are not easily available in developing countries. Nicole Kuepper's low cost and low-tech solar cells could offer a way to remove the dependence of developing countries on greenhouse gas-producing energy sources.

Solar cell production
A typical photovoltaic cell is made of a thin boron doped (doping a process of introducing impurities into a pure semi-conductor) P-type (P for positive) silicon wafer with positively charged 'holes' (missing electrons). One side of this original wafer is then doped with phosphorus to create extra electrons, and is called N-type (N for negative). Where the P and N-type silicon meet a junction is created that separates electrons and holes when exposed to light. Metal contact is made to both the P and N-type silicon allowing electrons to flow out of the N-type silicon, through a light bulb and back around to the P-type silicon. This movement of electrons constitutes an electric current - thus converting light into electricity!

Kuepper explains the iJET technique:
"To pattern the cell we spray on something like nail polish and then inkjet print a kind of nail polish remover which lets us etch certain parts of the wafer. This creates a metallisation pattern so we can deposit aluminium on the back surface of the solar cell and create our metal contacts to both the P and N-type silicon simultaneously using a very cheap, low temperature pizza oven! And hey presto we've created a simple, low-cost solar cell without having to use expensive high tech equipment or high temperature processes!"

Nicole is busy creating prototypes of the device and working toward implementing the technology in a commercial production environment.