Study could pave the way for cheap and efficient solar cells

A new study shows that efficient solar cell structures can be made by using simple and inexpensive manufacturing methods where flexible layers of material are deposited over large areas.

The study, published in the journal Advanced Energy Materials, is said to pave the way for new solar cell manufacturing techniques and the promise of developments in renewable solar energy.

Scientists from the universities of Sheffield and Cambridge used the ISIS Neutron Source and Diamond Light Source at STFC Rutherford Appleton Laboratory in Oxfordshire to carry out the research.

Plastic (polymer) solar cells are claimed to be much cheaper to produce than conventional silicon solar cells and have the potential to be produced in large quantities.

The study showed that when complex mixtures of molecules in solution are spread onto a surface, the different molecules separate to the top and bottom of the layer in a way that maximises the efficiency of the resulting solar cell. 

Sheffield’s Dr Andrew Parnell said: ‘Our results give important insights into how ultra-cheap solar energy panels for domestic and industrial use can be manufactured on a large scale.’

Dr Robert Dalgliesh, an ISIS scientist involved in the work, added: ‘Using neutron beams at ISIS and Diamond’s bright X-rays, we were able to probe the internal structure and properties of the solar cell materials non-destructively.

‘By studying the layers in the materials that convert sunlight into electricity, we are learning how different processing steps change the overall efficiency and affect the overall polymer solar cell performance.’

‘In a couple of hours enough energy from sunlight falls on the Earth to satisfy the energy needs of the Earth for a whole year, but we need to be able to harness this on a much bigger scale than we can do now,’ said Prof Richard Jones of Sheffield University. ‘Cheap and efficient polymer solar cells that can cover huge areas could help move us into a new age of renewable energy.’

The research was funded with a grant from the Engineering and Physical Sciences Research Council (EPSRC). 

The collaboration has been allocated a new grant to carry out further studies into the structure and function of polymer solar cell materials, as well as examining new materials and processes for high-volume manufacture and future commercialisation.