Nanowires for solar energy

Nanowires for solar energy

Solar energy is rapidly gaining ground, but cut-throat competition in the sector means that companies have to be able to supply solar cells with increasingly high performance at a low cost. It has long been known that solar cells with gallium arsenide absorb solar energy more efficiently than silicon cells. However, gallium arsenide is expensive, so solar cells in this material have mainly been used in very advanced applications – such as energy supply to satellites and space stations. The research company Sol Voltaics has developed a method which enables the advantages of gallium arsenide to be exploited on a large scale, at a competitive price.

“The equipment at MAX IV Laboratory gave us the opportunity to study our material in completely new ways. We are keen to come back and conduct new experiments.”

After many years of research, Sol Voltaics’ technology is now at the pilot stage. A machine capable of producing solar cells of approximately one square metre is currently under construction, and the commercial production is expected to begin within a couple of years.

Of course, continuous production of nanowires requires extreme precision. Therefore, being able to line up these almost inconceivably thin wires according to a precise pattern can seem completely impossible to an outsider.

“These structures are completely invisible to the naked eye and cannot be mechanically processed. We use chemical compounds, which bind molecules to the surface of the wires to get them to line up. It was this method we wanted to evaluate with our experiments at MAX IV Laboratory. The equipment there gave us the opportunity to study our material in completely new ways.”

The results of the experiments were not quite what they expected, but they provided Sol Voltaics with important knowledge for the continued development of their product.

‟Among other things, we realised how our tests are to be designed so as to get the most information possible out of the experiments. Now that we have been home and ‘done our homework’, we are keen to come back and conduct new experiments.”

Sol Voltaics visited the SPELEEM instrument at the I311 beamline at MAX IV Laboratory. SPELEEM stands for Spectroscopic Photo Emission and Low Energy Electron Microscope, and offers researchers the opportunity to produce both microscopy images with nanometer precision of various materials, and at the same time investigate the chemical, structural and electronic properties of their surfaces.