After Gutenberg

Photo Credit: Murray Wilson / Manawatu Standard

Wayne Campbell, left, and Ashton Partridge with a tiny demonstration solar panel filled with synthetic dye. “We now have the most efficient porphyrin dye in the world,” said Partridge, Massey’s new director of the Nanomaterials Research Centre.

When reporting that material scientists in China, Europe, Japan and the US have been focussed on dye-sensitized nano structure solar cells, I was unaware of research at Massey University.

Material scientists at this New Zealand Nanomaterials Research Centre also have made progress on solar panel filled with synthetic dye that not only is environmentally friendly, but it also could cost a fraction of the price of silicon cells. “While others are doing related work, in this aspect we are the world leaders,” said Wayne Campbell in a April 5 interview with Mervyn Dykes of the Manawatu Standard.

Titanium dioxide solar cells are cheaper and cleaner to manufacture than traditional silicon solar cells. After 15 years of research there seems to progress in developing an efficient dye-sensitized solar cell. DyeSol has begun manufacture of titanium dioxide solar cells.

The basic material is an abundant, non-toxic, mineral — titanium dioxide — commonly used in pharmaceuticals, toothpaste, cosmetics, etc. Thus, these solar cells are more environmentally friendly that other types of solar cells.

Another advantage is that 10 micron thick layer of dye-sensitized titania nanocrystals form an optically transparent film of titanium dioxide, so that we soon may see the use of low-cost, dye-sensitized solar cells in everyday places, e.g., roofing materials, tinted window glass and wall panels.

* Note: In 1991, Michael Graetzel reported that controlled formation of highly organized mesoporous titania thin films can achieve photo-sensitization over a wide-band-gap. Such a low-cost solar cell also can be highly efficient. A mono-layer of a charge-transfer dye provides the colloidal TiO2 films with spectral characteristics, which enable a high proportion of the incident solar energy flux (46%) to be harvested. Tests have shown “exceptionally high efficiencies for the conversion of incident photons to electrical current (more than 80%).

The overall light-to-electric energy conversion yield is 7.1-7.9% in simulated solar light and 12% in diffuse daylight. While this is lower efficiency compared to solid-state cells, the lower costs of manufacturing may give dye-sensitized solar cells an important niche in a rapidly growing market.